diff --git a/camera/common/1.0/default/Android.bp b/camera/common/1.0/default/Android.bp
index 4a5ca83..1a4d16b 100644
--- a/camera/common/1.0/default/Android.bp
+++ b/camera/common/1.0/default/Android.bp
@@ -18,6 +18,7 @@
         "VendorTagDescriptor.cpp",
         "HandleImporter.cpp",
         "Exif.cpp",
+        "SimpleThread.cpp",
     ],
     cflags: [
         "-Werror",
diff --git a/camera/common/1.0/default/SimpleThread.cpp b/camera/common/1.0/default/SimpleThread.cpp
new file mode 100644
index 0000000..46e89ba
--- /dev/null
+++ b/camera/common/1.0/default/SimpleThread.cpp
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "SimpleThread.h"
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace common {
+namespace helper {
+
+SimpleThread::SimpleThread() : mDone(true), mThread() {}
+SimpleThread::~SimpleThread() {
+    // Safe to call requestExitAndWait() from the destructor because requestExitAndWait() ensures
+    // that the thread is joinable before joining on it. This is different from how
+    // android::Thread worked.
+    requestExitAndWait();
+}
+
+void SimpleThread::run() {
+    requestExitAndWait();  // Exit current execution, if any.
+
+    // start thread
+    mDone.store(false, std::memory_order_release);
+    mThread = std::thread(&SimpleThread::runLoop, this);
+}
+
+void SimpleThread::requestExitAndWait() {
+    // Signal thread to stop
+    mDone.store(true, std::memory_order_release);
+
+    // Wait for thread to exit if needed. This should happen in no more than one iteration of
+    // threadLoop
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+    mThread = std::thread();
+}
+
+void SimpleThread::runLoop() {
+    while (!exitPending()) {
+        if (!threadLoop()) {
+            break;
+        }
+    }
+}
+
+}  // namespace helper
+}  // namespace common
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/camera/common/1.0/default/include/SimpleThread.h b/camera/common/1.0/default/include/SimpleThread.h
new file mode 100644
index 0000000..d1becd6
--- /dev/null
+++ b/camera/common/1.0/default/include/SimpleThread.h
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_COMMON_SIMPLETHREAD_H_
+#define HARDWARE_INTERFACES_CAMERA_COMMON_SIMPLETHREAD_H_
+
+#include <thread>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace common {
+namespace helper {
+
+// A simple looper based on std::thread.
+class SimpleThread {
+  public:
+    SimpleThread();
+    virtual ~SimpleThread();
+
+    // Explicit call to start execution of the thread. No thread is created before this function
+    // is called.
+    virtual void run() final;
+    virtual void requestExitAndWait() final;
+
+  protected:
+    // Main logic of the thread. This function is called repeatedly until it returns false.
+    // Thread execution stops if this function returns false.
+    virtual bool threadLoop() = 0;
+
+    // Returns true if the thread execution should stop. Should be used by threadLoop to check if
+    // the thread has been requested to exit.
+    virtual inline bool exitPending() final { return mDone.load(std::memory_order_acquire); }
+
+  private:
+    // Wraps threadLoop in a simple while loop that allows safe exit
+    virtual void runLoop() final;
+
+    // Flag to signal end of thread execution. This flag is checked before every iteration
+    // of threadLoop.
+    std::atomic_bool mDone;
+    std::thread mThread;
+};
+
+}  // namespace helper
+}  // namespace common
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_COMMON_SIMPLETHREAD_H_
diff --git a/camera/device/default/Android.bp b/camera/device/default/Android.bp
new file mode 100644
index 0000000..b577597
--- /dev/null
+++ b/camera/device/default/Android.bp
@@ -0,0 +1,71 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "hardware_interfaces_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["hardware_interfaces_license"],
+}
+
+cc_library_shared {
+    name: "camera.device-external-impl",
+    defaults: ["hidl_defaults"],
+    proprietary: true,
+    srcs: [
+        "ExternalCameraDevice.cpp",
+        "ExternalCameraDeviceSession.cpp",
+        "ExternalCameraOfflineSession.cpp",
+        "ExternalCameraUtils.cpp",
+        "convert.cpp",
+    ],
+    shared_libs: [
+        "android.hardware.camera.common-V1-ndk",
+        "android.hardware.camera.device-V1-ndk",
+        "android.hardware.graphics.allocator-V1-ndk",
+        "android.hardware.graphics.common-V4-ndk",
+        "android.hardware.graphics.mapper@2.0",
+        "android.hardware.graphics.mapper@3.0",
+        "android.hardware.graphics.mapper@4.0",
+        "android.hidl.allocator@1.0",
+        "android.hidl.memory@1.0",
+        "libbinder_ndk",
+        "libcamera_metadata",
+        "libcutils",
+        "libexif",
+        "libfmq",
+        "libgralloctypes",
+        "libhardware",
+        "libhidlbase",
+        "libhidlmemory",
+        "libjpeg",
+        "liblog",
+        "libsync",
+        "libtinyxml2",
+        "libutils",
+        "libyuv",
+    ],
+    static_libs: [
+        "android.hardware.camera.common@1.0-helper",
+        "libaidlcommonsupport",
+    ],
+    header_libs: [
+        "media_plugin_headers",
+    ],
+    export_include_dirs: ["."],
+}
diff --git a/camera/device/default/ExternalCameraDevice.cpp b/camera/device/default/ExternalCameraDevice.cpp
new file mode 100644
index 0000000..677fb42
--- /dev/null
+++ b/camera/device/default/ExternalCameraDevice.cpp
@@ -0,0 +1,1001 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ExtCamDev"
+// #define LOG_NDEBUG 0
+#include <log/log.h>
+
+#include "ExternalCameraDevice.h"
+
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <convert.h>
+#include <linux/videodev2.h>
+#include <regex>
+#include <set>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::Status;
+
+namespace {
+// Only support MJPEG for now as it seems to be the one supports higher fps
+// Other formats to consider in the future:
+// * V4L2_PIX_FMT_YVU420 (== YV12)
+// * V4L2_PIX_FMT_YVYU (YVYU: can be converted to YV12 or other YUV420_888 formats)
+const std::array<uint32_t, /*size*/ 2> kSupportedFourCCs{
+        {V4L2_PIX_FMT_MJPEG, V4L2_PIX_FMT_Z16}};  // double braces required in C++11
+
+constexpr int MAX_RETRY = 5;                  // Allow retry v4l2 open failures a few times.
+constexpr int OPEN_RETRY_SLEEP_US = 100'000;  // 100ms * MAX_RETRY = 0.5 seconds
+
+const std::regex kDevicePathRE("/dev/video([0-9]+)");
+}  // namespace
+
+std::string ExternalCameraDevice::kDeviceVersion = "1.1";
+
+ExternalCameraDevice::ExternalCameraDevice(const std::string& devicePath,
+                                           const ExternalCameraConfig& config)
+    : mCameraId("-1"), mDevicePath(devicePath), mCfg(config) {
+    std::smatch sm;
+    if (std::regex_match(mDevicePath, sm, kDevicePathRE)) {
+        mCameraId = std::to_string(mCfg.cameraIdOffset + std::stoi(sm[1]));
+    } else {
+        ALOGE("%s: device path match failed for %s", __FUNCTION__, mDevicePath.c_str());
+    }
+}
+
+ExternalCameraDevice::~ExternalCameraDevice() {}
+
+ndk::ScopedAStatus ExternalCameraDevice::getCameraCharacteristics(CameraMetadata* _aidl_return) {
+    Mutex::Autolock _l(mLock);
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    if (isInitFailedLocked()) {
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    const camera_metadata_t* rawMetadata = mCameraCharacteristics.getAndLock();
+    convertToAidl(rawMetadata, _aidl_return);
+    mCameraCharacteristics.unlock(rawMetadata);
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::getPhysicalCameraCharacteristics(const std::string&,
+                                                                          CameraMetadata*) {
+    ALOGE("%s: Physical camera functions are not supported for external cameras.", __FUNCTION__);
+    return fromStatus(Status::ILLEGAL_ARGUMENT);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::getResourceCost(CameraResourceCost* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    _aidl_return->resourceCost = 100;
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::isStreamCombinationSupported(
+        const StreamConfiguration& in_streams, bool* _aidl_return) {
+    if (isInitFailed()) {
+        ALOGE("%s: camera %s. camera init failed!", __FUNCTION__, mCameraId.c_str());
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+    Status s = ExternalCameraDeviceSession::isStreamCombinationSupported(in_streams,
+                                                                         mSupportedFormats, mCfg);
+    *_aidl_return = s == Status::OK;
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::open(
+        const std::shared_ptr<ICameraDeviceCallback>& in_callback,
+        std::shared_ptr<ICameraDeviceSession>* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        ALOGE("%s: cannot open camera %s. return session ptr is null!", __FUNCTION__,
+              mCameraId.c_str());
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    Mutex::Autolock _l(mLock);
+    if (isInitFailedLocked()) {
+        ALOGE("%s: cannot open camera %s. camera init failed!", __FUNCTION__, mCameraId.c_str());
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    std::shared_ptr<ExternalCameraDeviceSession> session;
+    ALOGV("%s: Initializing device for camera %s", __FUNCTION__, mCameraId.c_str());
+    session = mSession.lock();
+
+    if (session != nullptr && !session->isClosed()) {
+        ALOGE("%s: cannot open an already opened camera!", __FUNCTION__);
+        return fromStatus(Status::CAMERA_IN_USE);
+    }
+
+    int numAttempt = 0;
+    unique_fd fd(::open(mDevicePath.c_str(), O_RDWR));
+    while (fd.get() < 0 && numAttempt < MAX_RETRY) {
+        // Previous retry attempts failed. Retry opening the device at most MAX_RETRY times
+        ALOGW("%s: v4l2 device %s open failed, wait 33ms and try again", __FUNCTION__,
+              mDevicePath.c_str());
+        usleep(OPEN_RETRY_SLEEP_US);  // sleep and try again
+        fd.reset(::open(mDevicePath.c_str(), O_RDWR));
+        numAttempt++;
+    }
+
+    if (fd.get() < 0) {
+        ALOGE("%s: v4l2 device open %s failed: %s", __FUNCTION__, mDevicePath.c_str(),
+              strerror(errno));
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    session = createSession(in_callback, mCfg, mSupportedFormats, mCroppingType,
+                            mCameraCharacteristics, mCameraId, std::move(fd));
+    if (session == nullptr) {
+        ALOGE("%s: camera device session allocation failed", __FUNCTION__);
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    if (session->isInitFailed()) {
+        ALOGE("%s: camera device session init failed", __FUNCTION__);
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    mSession = session;
+    *_aidl_return = session;
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::openInjectionSession(
+        const std::shared_ptr<ICameraDeviceCallback>&, std::shared_ptr<ICameraInjectionSession>*) {
+    return fromStatus(Status::OPERATION_NOT_SUPPORTED);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::setTorchMode(bool) {
+    return fromStatus(Status::OPERATION_NOT_SUPPORTED);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::turnOnTorchWithStrengthLevel(int32_t) {
+    return fromStatus(Status::OPERATION_NOT_SUPPORTED);
+}
+
+ndk::ScopedAStatus ExternalCameraDevice::getTorchStrengthLevel(int32_t*) {
+    return fromStatus(Status::OPERATION_NOT_SUPPORTED);
+}
+
+std::shared_ptr<ExternalCameraDeviceSession> ExternalCameraDevice::createSession(
+        const std::shared_ptr<ICameraDeviceCallback>& cb, const ExternalCameraConfig& cfg,
+        const std::vector<SupportedV4L2Format>& sortedFormats, const CroppingType& croppingType,
+        const common::V1_0::helper::CameraMetadata& chars, const std::string& cameraId,
+        unique_fd v4l2Fd) {
+    return ndk::SharedRefBase::make<ExternalCameraDeviceSession>(
+            cb, cfg, sortedFormats, croppingType, chars, cameraId, std::move(v4l2Fd));
+}
+
+bool ExternalCameraDevice::isInitFailed() {
+    Mutex::Autolock _l(mLock);
+    return isInitFailedLocked();
+}
+
+bool ExternalCameraDevice::isInitFailedLocked() {
+    if (!mInitialized) {
+        status_t ret = initCameraCharacteristics();
+        if (ret != OK) {
+            ALOGE("%s: init camera characteristics failed: errorno %d", __FUNCTION__, ret);
+            mInitFailed = true;
+        }
+        mInitialized = true;
+    }
+    return mInitFailed;
+}
+
+void ExternalCameraDevice::initSupportedFormatsLocked(int fd) {
+    std::vector<SupportedV4L2Format> horizontalFmts =
+            getCandidateSupportedFormatsLocked(fd, HORIZONTAL, mCfg.fpsLimits, mCfg.depthFpsLimits,
+                                               mCfg.minStreamSize, mCfg.depthEnabled);
+    std::vector<SupportedV4L2Format> verticalFmts =
+            getCandidateSupportedFormatsLocked(fd, VERTICAL, mCfg.fpsLimits, mCfg.depthFpsLimits,
+                                               mCfg.minStreamSize, mCfg.depthEnabled);
+
+    size_t horiSize = horizontalFmts.size();
+    size_t vertSize = verticalFmts.size();
+
+    if (horiSize == 0 && vertSize == 0) {
+        ALOGE("%s: cannot find suitable cropping type!", __FUNCTION__);
+        return;
+    }
+
+    if (horiSize == 0) {
+        mSupportedFormats = verticalFmts;
+        mCroppingType = VERTICAL;
+        return;
+    } else if (vertSize == 0) {
+        mSupportedFormats = horizontalFmts;
+        mCroppingType = HORIZONTAL;
+        return;
+    }
+
+    const auto& maxHoriSize = horizontalFmts[horizontalFmts.size() - 1];
+    const auto& maxVertSize = verticalFmts[verticalFmts.size() - 1];
+
+    // Try to keep the largest possible output size
+    // When they are the same or ambiguous, pick the one support more sizes
+    if (maxHoriSize.width == maxVertSize.width && maxHoriSize.height == maxVertSize.height) {
+        if (horiSize > vertSize) {
+            mSupportedFormats = horizontalFmts;
+            mCroppingType = HORIZONTAL;
+        } else {
+            mSupportedFormats = verticalFmts;
+            mCroppingType = VERTICAL;
+        }
+    } else if (maxHoriSize.width >= maxVertSize.width && maxHoriSize.height >= maxVertSize.height) {
+        mSupportedFormats = horizontalFmts;
+        mCroppingType = HORIZONTAL;
+    } else if (maxHoriSize.width <= maxVertSize.width && maxHoriSize.height <= maxVertSize.height) {
+        mSupportedFormats = verticalFmts;
+        mCroppingType = VERTICAL;
+    } else {
+        if (horiSize > vertSize) {
+            mSupportedFormats = horizontalFmts;
+            mCroppingType = HORIZONTAL;
+        } else {
+            mSupportedFormats = verticalFmts;
+            mCroppingType = VERTICAL;
+        }
+    }
+}
+
+status_t ExternalCameraDevice::initCameraCharacteristics() {
+    if (!mCameraCharacteristics.isEmpty()) {
+        // Camera Characteristics previously initialized. Skip.
+        return OK;
+    }
+
+    // init camera characteristics
+    unique_fd fd(::open(mDevicePath.c_str(), O_RDWR));
+    if (fd.get() < 0) {
+        ALOGE("%s: v4l2 device open %s failed", __FUNCTION__, mDevicePath.c_str());
+        return DEAD_OBJECT;
+    }
+
+    status_t ret;
+    ret = initDefaultCharsKeys(&mCameraCharacteristics);
+    if (ret != OK) {
+        ALOGE("%s: init default characteristics key failed: errorno %d", __FUNCTION__, ret);
+        mCameraCharacteristics.clear();
+        return ret;
+    }
+
+    ret = initCameraControlsCharsKeys(fd.get(), &mCameraCharacteristics);
+    if (ret != OK) {
+        ALOGE("%s: init camera control characteristics key failed: errorno %d", __FUNCTION__, ret);
+        mCameraCharacteristics.clear();
+        return ret;
+    }
+
+    ret = initOutputCharsKeys(fd.get(), &mCameraCharacteristics);
+    if (ret != OK) {
+        ALOGE("%s: init output characteristics key failed: errorno %d", __FUNCTION__, ret);
+        mCameraCharacteristics.clear();
+        return ret;
+    }
+
+    ret = initAvailableCapabilities(&mCameraCharacteristics);
+    if (ret != OK) {
+        ALOGE("%s: init available capabilities key failed: errorno %d", __FUNCTION__, ret);
+        mCameraCharacteristics.clear();
+        return ret;
+    }
+
+    return OK;
+}
+
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+#define UPDATE(tag, data, size)                        \
+    do {                                               \
+        if (metadata->update((tag), (data), (size))) { \
+            ALOGE("Update " #tag " failed!");          \
+            return -EINVAL;                            \
+        }                                              \
+    } while (0)
+
+status_t ExternalCameraDevice::initAvailableCapabilities(
+        ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    if (mSupportedFormats.empty()) {
+        ALOGE("%s: Supported formats list is empty", __FUNCTION__);
+        return UNKNOWN_ERROR;
+    }
+
+    bool hasDepth = false;
+    bool hasColor = false;
+    for (const auto& fmt : mSupportedFormats) {
+        switch (fmt.fourcc) {
+            case V4L2_PIX_FMT_Z16:
+                hasDepth = true;
+                break;
+            case V4L2_PIX_FMT_MJPEG:
+                hasColor = true;
+                break;
+            default:
+                ALOGW("%s: Unsupported format found", __FUNCTION__);
+        }
+    }
+
+    std::vector<uint8_t> availableCapabilities;
+    if (hasDepth) {
+        availableCapabilities.push_back(ANDROID_REQUEST_AVAILABLE_CAPABILITIES_DEPTH_OUTPUT);
+    }
+    if (hasColor) {
+        availableCapabilities.push_back(ANDROID_REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE);
+    }
+    if (!availableCapabilities.empty()) {
+        UPDATE(ANDROID_REQUEST_AVAILABLE_CAPABILITIES, availableCapabilities.data(),
+               availableCapabilities.size());
+    }
+
+    return OK;
+}
+
+status_t ExternalCameraDevice::initDefaultCharsKeys(
+        ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    const uint8_t hardware_level = ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL_EXTERNAL;
+    UPDATE(ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL, &hardware_level, 1);
+
+    // android.colorCorrection
+    const uint8_t availableAberrationModes[] = {ANDROID_COLOR_CORRECTION_ABERRATION_MODE_OFF};
+    UPDATE(ANDROID_COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES, availableAberrationModes,
+           ARRAY_SIZE(availableAberrationModes));
+
+    // android.control
+    const uint8_t antibandingMode = ANDROID_CONTROL_AE_ANTIBANDING_MODE_AUTO;
+    UPDATE(ANDROID_CONTROL_AE_AVAILABLE_ANTIBANDING_MODES, &antibandingMode, 1);
+
+    const int32_t controlMaxRegions[] = {/*AE*/ 0, /*AWB*/ 0, /*AF*/ 0};
+    UPDATE(ANDROID_CONTROL_MAX_REGIONS, controlMaxRegions, ARRAY_SIZE(controlMaxRegions));
+
+    const uint8_t videoStabilizationMode = ANDROID_CONTROL_VIDEO_STABILIZATION_MODE_OFF;
+    UPDATE(ANDROID_CONTROL_AVAILABLE_VIDEO_STABILIZATION_MODES, &videoStabilizationMode, 1);
+
+    const uint8_t awbAvailableMode = ANDROID_CONTROL_AWB_MODE_AUTO;
+    UPDATE(ANDROID_CONTROL_AWB_AVAILABLE_MODES, &awbAvailableMode, 1);
+
+    const uint8_t aeAvailableMode = ANDROID_CONTROL_AE_MODE_ON;
+    UPDATE(ANDROID_CONTROL_AE_AVAILABLE_MODES, &aeAvailableMode, 1);
+
+    const uint8_t availableFffect = ANDROID_CONTROL_EFFECT_MODE_OFF;
+    UPDATE(ANDROID_CONTROL_AVAILABLE_EFFECTS, &availableFffect, 1);
+
+    const uint8_t controlAvailableModes[] = {ANDROID_CONTROL_MODE_OFF, ANDROID_CONTROL_MODE_AUTO};
+    UPDATE(ANDROID_CONTROL_AVAILABLE_MODES, controlAvailableModes,
+           ARRAY_SIZE(controlAvailableModes));
+
+    // android.edge
+    const uint8_t edgeMode = ANDROID_EDGE_MODE_OFF;
+    UPDATE(ANDROID_EDGE_AVAILABLE_EDGE_MODES, &edgeMode, 1);
+
+    // android.flash
+    const uint8_t flashInfo = ANDROID_FLASH_INFO_AVAILABLE_FALSE;
+    UPDATE(ANDROID_FLASH_INFO_AVAILABLE, &flashInfo, 1);
+
+    // android.hotPixel
+    const uint8_t hotPixelMode = ANDROID_HOT_PIXEL_MODE_OFF;
+    UPDATE(ANDROID_HOT_PIXEL_AVAILABLE_HOT_PIXEL_MODES, &hotPixelMode, 1);
+
+    // android.jpeg
+    const int32_t jpegAvailableThumbnailSizes[] = {0,   0,   176, 144, 240, 144, 256,
+                                                   144, 240, 160, 256, 154, 240, 180};
+    UPDATE(ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES, jpegAvailableThumbnailSizes,
+           ARRAY_SIZE(jpegAvailableThumbnailSizes));
+
+    const int32_t jpegMaxSize = mCfg.maxJpegBufSize;
+    UPDATE(ANDROID_JPEG_MAX_SIZE, &jpegMaxSize, 1);
+
+    // android.lens
+    const uint8_t focusDistanceCalibration =
+            ANDROID_LENS_INFO_FOCUS_DISTANCE_CALIBRATION_UNCALIBRATED;
+    UPDATE(ANDROID_LENS_INFO_FOCUS_DISTANCE_CALIBRATION, &focusDistanceCalibration, 1);
+
+    const uint8_t opticalStabilizationMode = ANDROID_LENS_OPTICAL_STABILIZATION_MODE_OFF;
+    UPDATE(ANDROID_LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION, &opticalStabilizationMode, 1);
+
+    const uint8_t facing = ANDROID_LENS_FACING_EXTERNAL;
+    UPDATE(ANDROID_LENS_FACING, &facing, 1);
+
+    // android.noiseReduction
+    const uint8_t noiseReductionMode = ANDROID_NOISE_REDUCTION_MODE_OFF;
+    UPDATE(ANDROID_NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES, &noiseReductionMode, 1);
+    UPDATE(ANDROID_NOISE_REDUCTION_MODE, &noiseReductionMode, 1);
+
+    const int32_t partialResultCount = 1;
+    UPDATE(ANDROID_REQUEST_PARTIAL_RESULT_COUNT, &partialResultCount, 1);
+
+    // This means pipeline latency of X frame intervals. The maximum number is 4.
+    const uint8_t requestPipelineMaxDepth = 4;
+    UPDATE(ANDROID_REQUEST_PIPELINE_MAX_DEPTH, &requestPipelineMaxDepth, 1);
+
+    // Three numbers represent the maximum numbers of different types of output
+    // streams simultaneously. The types are raw sensor, processed (but not
+    // stalling), and processed (but stalling). For usb limited mode, raw sensor
+    // is not supported. Stalling stream is JPEG. Non-stalling streams are
+    // YUV_420_888 or YV12.
+    const int32_t requestMaxNumOutputStreams[] = {
+            /*RAW*/ 0,
+            /*Processed*/ ExternalCameraDeviceSession::kMaxProcessedStream,
+            /*Stall*/ ExternalCameraDeviceSession::kMaxStallStream};
+    UPDATE(ANDROID_REQUEST_MAX_NUM_OUTPUT_STREAMS, requestMaxNumOutputStreams,
+           ARRAY_SIZE(requestMaxNumOutputStreams));
+
+    // Limited mode doesn't support reprocessing.
+    const int32_t requestMaxNumInputStreams = 0;
+    UPDATE(ANDROID_REQUEST_MAX_NUM_INPUT_STREAMS, &requestMaxNumInputStreams, 1);
+
+    // android.scaler
+    // TODO: b/72263447 V4L2_CID_ZOOM_*
+    const float scalerAvailableMaxDigitalZoom[] = {1};
+    UPDATE(ANDROID_SCALER_AVAILABLE_MAX_DIGITAL_ZOOM, scalerAvailableMaxDigitalZoom,
+           ARRAY_SIZE(scalerAvailableMaxDigitalZoom));
+
+    const uint8_t croppingType = ANDROID_SCALER_CROPPING_TYPE_CENTER_ONLY;
+    UPDATE(ANDROID_SCALER_CROPPING_TYPE, &croppingType, 1);
+
+    const int32_t testPatternModes[] = {ANDROID_SENSOR_TEST_PATTERN_MODE_OFF,
+                                        ANDROID_SENSOR_TEST_PATTERN_MODE_SOLID_COLOR};
+    UPDATE(ANDROID_SENSOR_AVAILABLE_TEST_PATTERN_MODES, testPatternModes,
+           ARRAY_SIZE(testPatternModes));
+
+    const uint8_t timestampSource = ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE_UNKNOWN;
+    UPDATE(ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE, &timestampSource, 1);
+
+    // Orientation is a bit odd for external camera, but consider it as the orientation
+    // between the external camera sensor (which is usually landscape) and the device's
+    // natural display orientation. For devices with natural landscape display (ex: tablet/TV), the
+    // orientation should be 0. For devices with natural portrait display (phone), the orientation
+    // should be 270.
+    const int32_t orientation = mCfg.orientation;
+    UPDATE(ANDROID_SENSOR_ORIENTATION, &orientation, 1);
+
+    // android.shading
+    const uint8_t availableMode = ANDROID_SHADING_MODE_OFF;
+    UPDATE(ANDROID_SHADING_AVAILABLE_MODES, &availableMode, 1);
+
+    // android.statistics
+    const uint8_t faceDetectMode = ANDROID_STATISTICS_FACE_DETECT_MODE_OFF;
+    UPDATE(ANDROID_STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES, &faceDetectMode, 1);
+
+    const int32_t maxFaceCount = 0;
+    UPDATE(ANDROID_STATISTICS_INFO_MAX_FACE_COUNT, &maxFaceCount, 1);
+
+    const uint8_t availableHotpixelMode = ANDROID_STATISTICS_HOT_PIXEL_MAP_MODE_OFF;
+    UPDATE(ANDROID_STATISTICS_INFO_AVAILABLE_HOT_PIXEL_MAP_MODES, &availableHotpixelMode, 1);
+
+    const uint8_t lensShadingMapMode = ANDROID_STATISTICS_LENS_SHADING_MAP_MODE_OFF;
+    UPDATE(ANDROID_STATISTICS_INFO_AVAILABLE_LENS_SHADING_MAP_MODES, &lensShadingMapMode, 1);
+
+    // android.sync
+    const int32_t maxLatency = ANDROID_SYNC_MAX_LATENCY_UNKNOWN;
+    UPDATE(ANDROID_SYNC_MAX_LATENCY, &maxLatency, 1);
+
+    /* Other sensor/RAW related keys:
+     * android.sensor.info.colorFilterArrangement -> no need if we don't do RAW
+     * android.sensor.info.physicalSize           -> not available
+     * android.sensor.info.whiteLevel             -> not available/not needed
+     * android.sensor.info.lensShadingApplied     -> not needed
+     * android.sensor.info.preCorrectionActiveArraySize -> not available/not needed
+     * android.sensor.blackLevelPattern           -> not available/not needed
+     */
+
+    const int32_t availableRequestKeys[] = {ANDROID_COLOR_CORRECTION_ABERRATION_MODE,
+                                            ANDROID_CONTROL_AE_ANTIBANDING_MODE,
+                                            ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION,
+                                            ANDROID_CONTROL_AE_LOCK,
+                                            ANDROID_CONTROL_AE_MODE,
+                                            ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER,
+                                            ANDROID_CONTROL_AE_TARGET_FPS_RANGE,
+                                            ANDROID_CONTROL_AF_MODE,
+                                            ANDROID_CONTROL_AF_TRIGGER,
+                                            ANDROID_CONTROL_AWB_LOCK,
+                                            ANDROID_CONTROL_AWB_MODE,
+                                            ANDROID_CONTROL_CAPTURE_INTENT,
+                                            ANDROID_CONTROL_EFFECT_MODE,
+                                            ANDROID_CONTROL_MODE,
+                                            ANDROID_CONTROL_SCENE_MODE,
+                                            ANDROID_CONTROL_VIDEO_STABILIZATION_MODE,
+                                            ANDROID_FLASH_MODE,
+                                            ANDROID_JPEG_ORIENTATION,
+                                            ANDROID_JPEG_QUALITY,
+                                            ANDROID_JPEG_THUMBNAIL_QUALITY,
+                                            ANDROID_JPEG_THUMBNAIL_SIZE,
+                                            ANDROID_LENS_OPTICAL_STABILIZATION_MODE,
+                                            ANDROID_NOISE_REDUCTION_MODE,
+                                            ANDROID_SCALER_CROP_REGION,
+                                            ANDROID_SENSOR_TEST_PATTERN_MODE,
+                                            ANDROID_STATISTICS_FACE_DETECT_MODE,
+                                            ANDROID_STATISTICS_HOT_PIXEL_MAP_MODE};
+    UPDATE(ANDROID_REQUEST_AVAILABLE_REQUEST_KEYS, availableRequestKeys,
+           ARRAY_SIZE(availableRequestKeys));
+
+    const int32_t availableResultKeys[] = {ANDROID_COLOR_CORRECTION_ABERRATION_MODE,
+                                           ANDROID_CONTROL_AE_ANTIBANDING_MODE,
+                                           ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION,
+                                           ANDROID_CONTROL_AE_LOCK,
+                                           ANDROID_CONTROL_AE_MODE,
+                                           ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER,
+                                           ANDROID_CONTROL_AE_STATE,
+                                           ANDROID_CONTROL_AE_TARGET_FPS_RANGE,
+                                           ANDROID_CONTROL_AF_MODE,
+                                           ANDROID_CONTROL_AF_STATE,
+                                           ANDROID_CONTROL_AF_TRIGGER,
+                                           ANDROID_CONTROL_AWB_LOCK,
+                                           ANDROID_CONTROL_AWB_MODE,
+                                           ANDROID_CONTROL_AWB_STATE,
+                                           ANDROID_CONTROL_CAPTURE_INTENT,
+                                           ANDROID_CONTROL_EFFECT_MODE,
+                                           ANDROID_CONTROL_MODE,
+                                           ANDROID_CONTROL_SCENE_MODE,
+                                           ANDROID_CONTROL_VIDEO_STABILIZATION_MODE,
+                                           ANDROID_FLASH_MODE,
+                                           ANDROID_FLASH_STATE,
+                                           ANDROID_JPEG_ORIENTATION,
+                                           ANDROID_JPEG_QUALITY,
+                                           ANDROID_JPEG_THUMBNAIL_QUALITY,
+                                           ANDROID_JPEG_THUMBNAIL_SIZE,
+                                           ANDROID_LENS_OPTICAL_STABILIZATION_MODE,
+                                           ANDROID_NOISE_REDUCTION_MODE,
+                                           ANDROID_REQUEST_PIPELINE_DEPTH,
+                                           ANDROID_SCALER_CROP_REGION,
+                                           ANDROID_SENSOR_TIMESTAMP,
+                                           ANDROID_STATISTICS_FACE_DETECT_MODE,
+                                           ANDROID_STATISTICS_HOT_PIXEL_MAP_MODE,
+                                           ANDROID_STATISTICS_LENS_SHADING_MAP_MODE,
+                                           ANDROID_STATISTICS_SCENE_FLICKER};
+    UPDATE(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS, availableResultKeys,
+           ARRAY_SIZE(availableResultKeys));
+
+    UPDATE(ANDROID_REQUEST_AVAILABLE_CHARACTERISTICS_KEYS, AVAILABLE_CHARACTERISTICS_KEYS.data(),
+           AVAILABLE_CHARACTERISTICS_KEYS.size());
+
+    return OK;
+}
+
+status_t ExternalCameraDevice::initCameraControlsCharsKeys(
+        int, ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    // android.sensor.info.sensitivityRange   -> V4L2_CID_ISO_SENSITIVITY
+    // android.sensor.info.exposureTimeRange  -> V4L2_CID_EXPOSURE_ABSOLUTE
+    // android.sensor.info.maxFrameDuration   -> TBD
+    // android.lens.info.minimumFocusDistance -> V4L2_CID_FOCUS_ABSOLUTE
+    // android.lens.info.hyperfocalDistance
+    // android.lens.info.availableFocalLengths -> not available?
+
+    // android.control
+    // No AE compensation support for now.
+    // TODO: V4L2_CID_EXPOSURE_BIAS
+    const int32_t controlAeCompensationRange[] = {0, 0};
+    UPDATE(ANDROID_CONTROL_AE_COMPENSATION_RANGE, controlAeCompensationRange,
+           ARRAY_SIZE(controlAeCompensationRange));
+    const camera_metadata_rational_t controlAeCompensationStep[] = {{0, 1}};
+    UPDATE(ANDROID_CONTROL_AE_COMPENSATION_STEP, controlAeCompensationStep,
+           ARRAY_SIZE(controlAeCompensationStep));
+
+    // TODO: Check V4L2_CID_AUTO_FOCUS_*.
+    const uint8_t afAvailableModes[] = {ANDROID_CONTROL_AF_MODE_AUTO, ANDROID_CONTROL_AF_MODE_OFF};
+    UPDATE(ANDROID_CONTROL_AF_AVAILABLE_MODES, afAvailableModes, ARRAY_SIZE(afAvailableModes));
+
+    // TODO: V4L2_CID_SCENE_MODE
+    const uint8_t availableSceneMode = ANDROID_CONTROL_SCENE_MODE_DISABLED;
+    UPDATE(ANDROID_CONTROL_AVAILABLE_SCENE_MODES, &availableSceneMode, 1);
+
+    // TODO: V4L2_CID_3A_LOCK
+    const uint8_t aeLockAvailable = ANDROID_CONTROL_AE_LOCK_AVAILABLE_FALSE;
+    UPDATE(ANDROID_CONTROL_AE_LOCK_AVAILABLE, &aeLockAvailable, 1);
+    const uint8_t awbLockAvailable = ANDROID_CONTROL_AWB_LOCK_AVAILABLE_FALSE;
+    UPDATE(ANDROID_CONTROL_AWB_LOCK_AVAILABLE, &awbLockAvailable, 1);
+
+    // TODO: V4L2_CID_ZOOM_*
+    const float scalerAvailableMaxDigitalZoom[] = {1};
+    UPDATE(ANDROID_SCALER_AVAILABLE_MAX_DIGITAL_ZOOM, scalerAvailableMaxDigitalZoom,
+           ARRAY_SIZE(scalerAvailableMaxDigitalZoom));
+
+    return OK;
+}
+
+status_t ExternalCameraDevice::initOutputCharsKeys(
+        int fd, ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    initSupportedFormatsLocked(fd);
+    if (mSupportedFormats.empty()) {
+        ALOGE("%s: Init supported format list failed", __FUNCTION__);
+        return UNKNOWN_ERROR;
+    }
+
+    bool hasDepth = false;
+    bool hasColor = false;
+
+    // For V4L2_PIX_FMT_Z16
+    std::array<int, /*size*/ 1> halDepthFormats{{HAL_PIXEL_FORMAT_Y16}};
+    // For V4L2_PIX_FMT_MJPEG
+    std::array<int, /*size*/ 3> halFormats{{HAL_PIXEL_FORMAT_BLOB, HAL_PIXEL_FORMAT_YCbCr_420_888,
+                                            HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED}};
+
+    for (const auto& supportedFormat : mSupportedFormats) {
+        switch (supportedFormat.fourcc) {
+            case V4L2_PIX_FMT_Z16:
+                hasDepth = true;
+                break;
+            case V4L2_PIX_FMT_MJPEG:
+                hasColor = true;
+                break;
+            default:
+                ALOGW("%s: format %c%c%c%c is not supported!", __FUNCTION__,
+                      supportedFormat.fourcc & 0xFF, (supportedFormat.fourcc >> 8) & 0xFF,
+                      (supportedFormat.fourcc >> 16) & 0xFF, (supportedFormat.fourcc >> 24) & 0xFF);
+        }
+    }
+
+    if (hasDepth) {
+        status_t ret = initOutputCharsKeysByFormat(
+                metadata, V4L2_PIX_FMT_Z16, halDepthFormats,
+                ANDROID_DEPTH_AVAILABLE_DEPTH_STREAM_CONFIGURATIONS_OUTPUT,
+                ANDROID_DEPTH_AVAILABLE_DEPTH_STREAM_CONFIGURATIONS,
+                ANDROID_DEPTH_AVAILABLE_DEPTH_MIN_FRAME_DURATIONS,
+                ANDROID_DEPTH_AVAILABLE_DEPTH_STALL_DURATIONS);
+        if (ret != OK) {
+            ALOGE("%s: Unable to initialize depth format keys: %s", __FUNCTION__,
+                  statusToString(ret).c_str());
+            return ret;
+        }
+    }
+    if (hasColor) {
+        status_t ret =
+                initOutputCharsKeysByFormat(metadata, V4L2_PIX_FMT_MJPEG, halFormats,
+                                            ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS_OUTPUT,
+                                            ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS,
+                                            ANDROID_SCALER_AVAILABLE_MIN_FRAME_DURATIONS,
+                                            ANDROID_SCALER_AVAILABLE_STALL_DURATIONS);
+        if (ret != OK) {
+            ALOGE("%s: Unable to initialize color format keys: %s", __FUNCTION__,
+                  statusToString(ret).c_str());
+            return ret;
+        }
+    }
+
+    status_t ret = calculateMinFps(metadata);
+    if (ret != OK) {
+        ALOGE("%s: Unable to update fps metadata: %s", __FUNCTION__, statusToString(ret).c_str());
+        return ret;
+    }
+
+    SupportedV4L2Format maximumFormat{.width = 0, .height = 0};
+    for (const auto& supportedFormat : mSupportedFormats) {
+        if (supportedFormat.width >= maximumFormat.width &&
+            supportedFormat.height >= maximumFormat.height) {
+            maximumFormat = supportedFormat;
+        }
+    }
+    int32_t activeArraySize[] = {0, 0, static_cast<int32_t>(maximumFormat.width),
+                                 static_cast<int32_t>(maximumFormat.height)};
+    UPDATE(ANDROID_SENSOR_INFO_PRE_CORRECTION_ACTIVE_ARRAY_SIZE, activeArraySize,
+           ARRAY_SIZE(activeArraySize));
+    UPDATE(ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE, activeArraySize, ARRAY_SIZE(activeArraySize));
+
+    int32_t pixelArraySize[] = {static_cast<int32_t>(maximumFormat.width),
+                                static_cast<int32_t>(maximumFormat.height)};
+    UPDATE(ANDROID_SENSOR_INFO_PIXEL_ARRAY_SIZE, pixelArraySize, ARRAY_SIZE(pixelArraySize));
+    return OK;
+}
+
+template <size_t SIZE>
+status_t ExternalCameraDevice::initOutputCharsKeysByFormat(
+        ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata,
+        uint32_t fourcc, const std::array<int, SIZE>& halFormats, int streamConfigTag,
+        int streamConfigurationKey, int minFrameDurationKey, int stallDurationKey) {
+    if (mSupportedFormats.empty()) {
+        ALOGE("%s: Init supported format list failed", __FUNCTION__);
+        return UNKNOWN_ERROR;
+    }
+
+    std::vector<int32_t> streamConfigurations;
+    std::vector<int64_t> minFrameDurations;
+    std::vector<int64_t> stallDurations;
+
+    for (const auto& supportedFormat : mSupportedFormats) {
+        if (supportedFormat.fourcc != fourcc) {
+            // Skip 4CCs not meant for the halFormats
+            continue;
+        }
+        for (const auto& format : halFormats) {
+            streamConfigurations.push_back(format);
+            streamConfigurations.push_back(supportedFormat.width);
+            streamConfigurations.push_back(supportedFormat.height);
+            streamConfigurations.push_back(streamConfigTag);
+        }
+
+        int64_t minFrameDuration = std::numeric_limits<int64_t>::max();
+        for (const auto& fr : supportedFormat.frameRates) {
+            // 1000000000LL < (2^32 - 1) and
+            // fr.durationNumerator is uint32_t, so no overflow here
+            int64_t frameDuration = 1000000000LL * fr.durationNumerator / fr.durationDenominator;
+            if (frameDuration < minFrameDuration) {
+                minFrameDuration = frameDuration;
+            }
+        }
+
+        for (const auto& format : halFormats) {
+            minFrameDurations.push_back(format);
+            minFrameDurations.push_back(supportedFormat.width);
+            minFrameDurations.push_back(supportedFormat.height);
+            minFrameDurations.push_back(minFrameDuration);
+        }
+
+        // The stall duration is 0 for non-jpeg formats. For JPEG format, stall
+        // duration can be 0 if JPEG is small. Here we choose 1 sec for JPEG.
+        // TODO: b/72261675. Maybe set this dynamically
+        for (const auto& format : halFormats) {
+            const int64_t NS_TO_SECOND = 1E9;
+            int64_t stall_duration = (format == HAL_PIXEL_FORMAT_BLOB) ? NS_TO_SECOND : 0;
+            stallDurations.push_back(format);
+            stallDurations.push_back(supportedFormat.width);
+            stallDurations.push_back(supportedFormat.height);
+            stallDurations.push_back(stall_duration);
+        }
+    }
+
+    UPDATE(streamConfigurationKey, streamConfigurations.data(), streamConfigurations.size());
+
+    UPDATE(minFrameDurationKey, minFrameDurations.data(), minFrameDurations.size());
+
+    UPDATE(stallDurationKey, stallDurations.data(), stallDurations.size());
+
+    return OK;
+}
+
+status_t ExternalCameraDevice::calculateMinFps(
+        ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata) {
+    std::set<int32_t> framerates;
+    int32_t minFps = std::numeric_limits<int32_t>::max();
+
+    for (const auto& supportedFormat : mSupportedFormats) {
+        for (const auto& fr : supportedFormat.frameRates) {
+            int32_t frameRateInt = static_cast<int32_t>(fr.getFramesPerSecond());
+            if (minFps > frameRateInt) {
+                minFps = frameRateInt;
+            }
+            framerates.insert(frameRateInt);
+        }
+    }
+
+    std::vector<int32_t> fpsRanges;
+    // FPS ranges
+    for (const auto& framerate : framerates) {
+        // Empirical: webcams often have close to 2x fps error and cannot support fixed fps range
+        fpsRanges.push_back(framerate / 2);
+        fpsRanges.push_back(framerate);
+    }
+    minFps /= 2;
+    int64_t maxFrameDuration = 1000000000LL / minFps;
+
+    UPDATE(ANDROID_CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES, fpsRanges.data(), fpsRanges.size());
+
+    UPDATE(ANDROID_SENSOR_INFO_MAX_FRAME_DURATION, &maxFrameDuration, 1);
+
+    return OK;
+}
+
+#undef ARRAY_SIZE
+#undef UPDATE
+
+void ExternalCameraDevice::getFrameRateList(int fd, double fpsUpperBound,
+                                            SupportedV4L2Format* format) {
+    format->frameRates.clear();
+
+    v4l2_frmivalenum frameInterval{
+            .index = 0,
+            .pixel_format = format->fourcc,
+            .width = static_cast<__u32>(format->width),
+            .height = static_cast<__u32>(format->height),
+    };
+
+    for (frameInterval.index = 0;
+         TEMP_FAILURE_RETRY(ioctl(fd, VIDIOC_ENUM_FRAMEINTERVALS, &frameInterval)) == 0;
+         ++frameInterval.index) {
+        if (frameInterval.type == V4L2_FRMIVAL_TYPE_DISCRETE) {
+            if (frameInterval.discrete.numerator != 0) {
+                SupportedV4L2Format::FrameRate fr = {frameInterval.discrete.numerator,
+                                                     frameInterval.discrete.denominator};
+                double framerate = fr.getFramesPerSecond();
+                if (framerate > fpsUpperBound) {
+                    continue;
+                }
+                ALOGV("index:%d, format:%c%c%c%c, w %d, h %d, framerate %f", frameInterval.index,
+                      frameInterval.pixel_format & 0xFF, (frameInterval.pixel_format >> 8) & 0xFF,
+                      (frameInterval.pixel_format >> 16) & 0xFF,
+                      (frameInterval.pixel_format >> 24) & 0xFF, frameInterval.width,
+                      frameInterval.height, framerate);
+                format->frameRates.push_back(fr);
+            }
+        }
+    }
+
+    if (format->frameRates.empty()) {
+        ALOGE("%s: failed to get supported frame rates for format:%c%c%c%c w %d h %d", __FUNCTION__,
+              frameInterval.pixel_format & 0xFF, (frameInterval.pixel_format >> 8) & 0xFF,
+              (frameInterval.pixel_format >> 16) & 0xFF, (frameInterval.pixel_format >> 24) & 0xFF,
+              frameInterval.width, frameInterval.height);
+    }
+}
+
+void ExternalCameraDevice::updateFpsBounds(
+        int fd, CroppingType cropType,
+        const std::vector<ExternalCameraConfig::FpsLimitation>& fpsLimits,
+        SupportedV4L2Format format, std::vector<SupportedV4L2Format>& outFmts) {
+    double fpsUpperBound = -1.0;
+    for (const auto& limit : fpsLimits) {
+        if (cropType == VERTICAL) {
+            if (format.width <= limit.size.width) {
+                fpsUpperBound = limit.fpsUpperBound;
+                break;
+            }
+        } else {  // HORIZONTAL
+            if (format.height <= limit.size.height) {
+                fpsUpperBound = limit.fpsUpperBound;
+                break;
+            }
+        }
+    }
+    if (fpsUpperBound < 0.f) {
+        return;
+    }
+
+    getFrameRateList(fd, fpsUpperBound, &format);
+    if (!format.frameRates.empty()) {
+        outFmts.push_back(format);
+    }
+}
+
+std::vector<SupportedV4L2Format> ExternalCameraDevice::getCandidateSupportedFormatsLocked(
+        int fd, CroppingType cropType,
+        const std::vector<ExternalCameraConfig::FpsLimitation>& fpsLimits,
+        const std::vector<ExternalCameraConfig::FpsLimitation>& depthFpsLimits,
+        const Size& minStreamSize, bool depthEnabled) {
+    std::vector<SupportedV4L2Format> outFmts;
+    struct v4l2_fmtdesc fmtdesc {
+        .index = 0, .type = V4L2_BUF_TYPE_VIDEO_CAPTURE
+    };
+    int ret = 0;
+    while (ret == 0) {
+        ret = TEMP_FAILURE_RETRY(ioctl(fd, VIDIOC_ENUM_FMT, &fmtdesc));
+        ALOGV("index:%d,ret:%d, format:%c%c%c%c", fmtdesc.index, ret, fmtdesc.pixelformat & 0xFF,
+              (fmtdesc.pixelformat >> 8) & 0xFF, (fmtdesc.pixelformat >> 16) & 0xFF,
+              (fmtdesc.pixelformat >> 24) & 0xFF);
+
+        if (ret != 0 || (fmtdesc.flags & V4L2_FMT_FLAG_EMULATED)) {
+            // Skip if IOCTL failed, or if the format is emulated
+            fmtdesc.index++;
+            continue;
+        }
+        auto it =
+                std::find(kSupportedFourCCs.begin(), kSupportedFourCCs.end(), fmtdesc.pixelformat);
+        if (it == kSupportedFourCCs.end()) {
+            fmtdesc.index++;
+            continue;
+        }
+
+        // Found supported format
+        v4l2_frmsizeenum frameSize{.index = 0, .pixel_format = fmtdesc.pixelformat};
+        for (; TEMP_FAILURE_RETRY(ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &frameSize)) == 0;
+             ++frameSize.index) {
+            if (frameSize.type == V4L2_FRMSIZE_TYPE_DISCRETE) {
+                ALOGV("index:%d, format:%c%c%c%c, w %d, h %d", frameSize.index,
+                      fmtdesc.pixelformat & 0xFF, (fmtdesc.pixelformat >> 8) & 0xFF,
+                      (fmtdesc.pixelformat >> 16) & 0xFF, (fmtdesc.pixelformat >> 24) & 0xFF,
+                      frameSize.discrete.width, frameSize.discrete.height);
+
+                // Disregard h > w formats so all aspect ratio (h/w) <= 1.0
+                // This will simplify the crop/scaling logic down the road
+                if (frameSize.discrete.height > frameSize.discrete.width) {
+                    continue;
+                }
+
+                // Discard all formats which is smaller than minStreamSize
+                if (frameSize.discrete.width < minStreamSize.width ||
+                    frameSize.discrete.height < minStreamSize.height) {
+                    continue;
+                }
+
+                SupportedV4L2Format format{
+                        .width = static_cast<int32_t>(frameSize.discrete.width),
+                        .height = static_cast<int32_t>(frameSize.discrete.height),
+                        .fourcc = fmtdesc.pixelformat};
+
+                if (format.fourcc == V4L2_PIX_FMT_Z16 && depthEnabled) {
+                    updateFpsBounds(fd, cropType, depthFpsLimits, format, outFmts);
+                } else {
+                    updateFpsBounds(fd, cropType, fpsLimits, format, outFmts);
+                }
+            }
+        }
+        fmtdesc.index++;
+    }
+    trimSupportedFormats(cropType, &outFmts);
+    return outFmts;
+}
+
+void ExternalCameraDevice::trimSupportedFormats(CroppingType cropType,
+                                                std::vector<SupportedV4L2Format>* pFmts) {
+    std::vector<SupportedV4L2Format>& sortedFmts = *pFmts;
+    if (cropType == VERTICAL) {
+        std::sort(sortedFmts.begin(), sortedFmts.end(),
+                  [](const SupportedV4L2Format& a, const SupportedV4L2Format& b) -> bool {
+                      if (a.width == b.width) {
+                          return a.height < b.height;
+                      }
+                      return a.width < b.width;
+                  });
+    } else {
+        std::sort(sortedFmts.begin(), sortedFmts.end(),
+                  [](const SupportedV4L2Format& a, const SupportedV4L2Format& b) -> bool {
+                      if (a.height == b.height) {
+                          return a.width < b.width;
+                      }
+                      return a.height < b.height;
+                  });
+    }
+
+    if (sortedFmts.empty()) {
+        ALOGE("%s: input format list is empty!", __FUNCTION__);
+        return;
+    }
+
+    const auto& maxSize = sortedFmts[sortedFmts.size() - 1];
+    float maxSizeAr = ASPECT_RATIO(maxSize);
+
+    // Remove formats that has aspect ratio not croppable from largest size
+    std::vector<SupportedV4L2Format> out;
+    for (const auto& fmt : sortedFmts) {
+        float ar = ASPECT_RATIO(fmt);
+        if (isAspectRatioClose(ar, maxSizeAr)) {
+            out.push_back(fmt);
+        } else if (cropType == HORIZONTAL && ar < maxSizeAr) {
+            out.push_back(fmt);
+        } else if (cropType == VERTICAL && ar > maxSizeAr) {
+            out.push_back(fmt);
+        } else {
+            ALOGV("%s: size (%d,%d) is removed due to unable to crop %s from (%d,%d)", __FUNCTION__,
+                  fmt.width, fmt.height, cropType == VERTICAL ? "vertically" : "horizontally",
+                  maxSize.width, maxSize.height);
+        }
+    }
+    sortedFmts = out;
+}
+
+binder_status_t ExternalCameraDevice::dump(int fd, const char** args, uint32_t numArgs) {
+    std::shared_ptr<ExternalCameraDeviceSession> session = mSession.lock();
+    if (session == nullptr) {
+        dprintf(fd, "No active camera device session instance\n");
+        return STATUS_OK;
+    }
+
+    return session->dump(fd, args, numArgs);
+}
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/camera/device/default/ExternalCameraDevice.h b/camera/device/default/ExternalCameraDevice.h
new file mode 100644
index 0000000..bcae194
--- /dev/null
+++ b/camera/device/default/ExternalCameraDevice.h
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICE_H_
+#define HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICE_H_
+
+#include <ExternalCameraDeviceSession.h>
+#include <ExternalCameraUtils.h>
+#include <aidl/android/hardware/camera/device/BnCameraDevice.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::CameraResourceCost;
+using ::aidl::android::hardware::camera::device::BnCameraDevice;
+using ::aidl::android::hardware::camera::device::CameraMetadata;
+using ::aidl::android::hardware::camera::device::ICameraDeviceCallback;
+using ::aidl::android::hardware::camera::device::ICameraDeviceSession;
+using ::aidl::android::hardware::camera::device::ICameraInjectionSession;
+using ::aidl::android::hardware::camera::device::StreamConfiguration;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+
+class ExternalCameraDevice : public BnCameraDevice {
+  public:
+    // Called by external camera provider HAL.
+    // Provider HAL must ensure the uniqueness of CameraDevice object per cameraId, or there could
+    // be multiple CameraDevice trying to access the same physical camera.  Also, provider will have
+    // to keep track of all CameraDevice objects in order to notify CameraDevice when the underlying
+    // camera is detached.
+    ExternalCameraDevice(const std::string& devicePath, const ExternalCameraConfig& config);
+    ~ExternalCameraDevice() override;
+
+    ndk::ScopedAStatus getCameraCharacteristics(CameraMetadata* _aidl_return) override;
+    ndk::ScopedAStatus getPhysicalCameraCharacteristics(const std::string& in_physicalCameraId,
+                                                        CameraMetadata* _aidl_return) override;
+    ndk::ScopedAStatus getResourceCost(CameraResourceCost* _aidl_return) override;
+    ndk::ScopedAStatus isStreamCombinationSupported(const StreamConfiguration& in_streams,
+                                                    bool* _aidl_return) override;
+    ndk::ScopedAStatus open(const std::shared_ptr<ICameraDeviceCallback>& in_callback,
+                            std::shared_ptr<ICameraDeviceSession>* _aidl_return) override;
+    ndk::ScopedAStatus openInjectionSession(
+            const std::shared_ptr<ICameraDeviceCallback>& in_callback,
+            std::shared_ptr<ICameraInjectionSession>* _aidl_return) override;
+    ndk::ScopedAStatus setTorchMode(bool in_on) override;
+    ndk::ScopedAStatus turnOnTorchWithStrengthLevel(int32_t in_torchStrength) override;
+    ndk::ScopedAStatus getTorchStrengthLevel(int32_t* _aidl_return) override;
+
+    binder_status_t dump(int fd, const char** args, uint32_t numArgs) override;
+
+    // Caller must use this method to check if CameraDevice ctor failed
+    bool isInitFailed();
+
+    // Device version to be used by the external camera provider.
+    // Should be of the form <major>.<minor>
+    static std::string kDeviceVersion;
+
+  private:
+    virtual std::shared_ptr<ExternalCameraDeviceSession> createSession(
+            const std::shared_ptr<ICameraDeviceCallback>&, const ExternalCameraConfig& cfg,
+            const std::vector<SupportedV4L2Format>& sortedFormats, const CroppingType& croppingType,
+            const common::V1_0::helper::CameraMetadata& chars, const std::string& cameraId,
+            unique_fd v4l2Fd);
+
+    bool isInitFailedLocked();
+
+    // Init supported w/h/format/fps in mSupportedFormats. Caller still owns fd
+    void initSupportedFormatsLocked(int fd);
+
+    // Calls into virtual member function. Do not use it in constructor
+    status_t initCameraCharacteristics();
+    // Init available capabilities keys
+    virtual status_t initAvailableCapabilities(
+            ::android::hardware::camera::common::V1_0::helper::CameraMetadata*);
+    // Init non-device dependent keys
+    virtual status_t initDefaultCharsKeys(
+            ::android::hardware::camera::common::V1_0::helper::CameraMetadata*);
+    // Init camera control chars keys. Caller still owns fd
+    status_t initCameraControlsCharsKeys(
+            int fd, ::android::hardware::camera::common::V1_0::helper::CameraMetadata*);
+    // Init camera output configuration related keys.  Caller still owns fd
+    status_t initOutputCharsKeys(
+            int fd, ::android::hardware::camera::common::V1_0::helper::CameraMetadata*);
+
+    // Helper function for initOutputCharskeys
+    template <size_t SIZE>
+    status_t initOutputCharsKeysByFormat(
+            ::android::hardware::camera::common::V1_0::helper::CameraMetadata* metadata,
+            uint32_t fourcc, const std::array<int, SIZE>& halFormats, int streamConfigTag,
+            int streamConfiguration, int minFrameDuration, int stallDuration);
+
+    status_t calculateMinFps(::android::hardware::camera::common::V1_0::helper::CameraMetadata*);
+
+    static void getFrameRateList(int fd, double fpsUpperBound, SupportedV4L2Format* format);
+
+    static void updateFpsBounds(int fd, CroppingType cropType,
+                                const std::vector<ExternalCameraConfig::FpsLimitation>& fpsLimits,
+                                SupportedV4L2Format format,
+                                std::vector<SupportedV4L2Format>& outFmts);
+
+    // Get candidate supported formats list of input cropping type.
+    static std::vector<SupportedV4L2Format> getCandidateSupportedFormatsLocked(
+            int fd, CroppingType cropType,
+            const std::vector<ExternalCameraConfig::FpsLimitation>& fpsLimits,
+            const std::vector<ExternalCameraConfig::FpsLimitation>& depthFpsLimits,
+            const Size& minStreamSize, bool depthEnabled);
+    // Trim supported format list by the cropping type. Also sort output formats by width/height
+    static void trimSupportedFormats(CroppingType cropType,
+                                     /*inout*/ std::vector<SupportedV4L2Format>* pFmts);
+
+    Mutex mLock;
+    bool mInitialized = false;
+    bool mInitFailed = false;
+    std::string mCameraId;
+    std::string mDevicePath;
+    const ExternalCameraConfig& mCfg;
+    std::vector<SupportedV4L2Format> mSupportedFormats;
+    CroppingType mCroppingType;
+
+    std::weak_ptr<ExternalCameraDeviceSession> mSession =
+            std::weak_ptr<ExternalCameraDeviceSession>();
+
+    ::android::hardware::camera::common::V1_0::helper::CameraMetadata mCameraCharacteristics;
+
+    const std::vector<int32_t> AVAILABLE_CHARACTERISTICS_KEYS = {
+            ANDROID_COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES,
+            ANDROID_CONTROL_AE_AVAILABLE_ANTIBANDING_MODES,
+            ANDROID_CONTROL_AE_AVAILABLE_MODES,
+            ANDROID_CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES,
+            ANDROID_CONTROL_AE_COMPENSATION_RANGE,
+            ANDROID_CONTROL_AE_COMPENSATION_STEP,
+            ANDROID_CONTROL_AE_LOCK_AVAILABLE,
+            ANDROID_CONTROL_AF_AVAILABLE_MODES,
+            ANDROID_CONTROL_AVAILABLE_EFFECTS,
+            ANDROID_CONTROL_AVAILABLE_MODES,
+            ANDROID_CONTROL_AVAILABLE_SCENE_MODES,
+            ANDROID_CONTROL_AVAILABLE_VIDEO_STABILIZATION_MODES,
+            ANDROID_CONTROL_AWB_AVAILABLE_MODES,
+            ANDROID_CONTROL_AWB_LOCK_AVAILABLE,
+            ANDROID_CONTROL_MAX_REGIONS,
+            ANDROID_FLASH_INFO_AVAILABLE,
+            ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL,
+            ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES,
+            ANDROID_LENS_FACING,
+            ANDROID_LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION,
+            ANDROID_LENS_INFO_FOCUS_DISTANCE_CALIBRATION,
+            ANDROID_NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES,
+            ANDROID_REQUEST_AVAILABLE_CAPABILITIES,
+            ANDROID_REQUEST_MAX_NUM_INPUT_STREAMS,
+            ANDROID_REQUEST_MAX_NUM_OUTPUT_STREAMS,
+            ANDROID_REQUEST_PARTIAL_RESULT_COUNT,
+            ANDROID_REQUEST_PIPELINE_MAX_DEPTH,
+            ANDROID_SCALER_AVAILABLE_MAX_DIGITAL_ZOOM,
+            ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS,
+            ANDROID_SCALER_CROPPING_TYPE,
+            ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE,
+            ANDROID_SENSOR_INFO_MAX_FRAME_DURATION,
+            ANDROID_SENSOR_INFO_PIXEL_ARRAY_SIZE,
+            ANDROID_SENSOR_INFO_PRE_CORRECTION_ACTIVE_ARRAY_SIZE,
+            ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE,
+            ANDROID_SENSOR_ORIENTATION,
+            ANDROID_SHADING_AVAILABLE_MODES,
+            ANDROID_STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES,
+            ANDROID_STATISTICS_INFO_AVAILABLE_HOT_PIXEL_MAP_MODES,
+            ANDROID_STATISTICS_INFO_AVAILABLE_LENS_SHADING_MAP_MODES,
+            ANDROID_STATISTICS_INFO_MAX_FACE_COUNT,
+            ANDROID_SYNC_MAX_LATENCY};
+};
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICE_H_
diff --git a/camera/device/default/ExternalCameraDeviceSession.cpp b/camera/device/default/ExternalCameraDeviceSession.cpp
new file mode 100644
index 0000000..68c6d2e
--- /dev/null
+++ b/camera/device/default/ExternalCameraDeviceSession.cpp
@@ -0,0 +1,2947 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ExtCamDevSsn"
+// #define LOG_NDEBUG 0
+#include <log/log.h>
+
+#include "ExternalCameraDeviceSession.h"
+
+#include <Exif.h>
+#include <ExternalCameraOfflineSession.h>
+#include <aidl/android/hardware/camera/device/CameraBlob.h>
+#include <aidl/android/hardware/camera/device/CameraBlobId.h>
+#include <aidl/android/hardware/camera/device/ErrorMsg.h>
+#include <aidl/android/hardware/camera/device/ShutterMsg.h>
+#include <aidl/android/hardware/camera/device/StreamBufferRet.h>
+#include <aidl/android/hardware/camera/device/StreamBuffersVal.h>
+#include <aidl/android/hardware/camera/device/StreamConfigurationMode.h>
+#include <aidl/android/hardware/camera/device/StreamRotation.h>
+#include <aidl/android/hardware/camera/device/StreamType.h>
+#include <aidl/android/hardware/graphics/common/Dataspace.h>
+#include <aidlcommonsupport/NativeHandle.h>
+#include <convert.h>
+#include <linux/videodev2.h>
+#include <sync/sync.h>
+#include <utils/Trace.h>
+#include <deque>
+
+#define HAVE_JPEG  // required for libyuv.h to export MJPEG decode APIs
+#include <libyuv.h>
+#include <libyuv/convert.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+namespace {
+
+// Size of request/result metadata fast message queue. Change to 0 to always use hwbinder buffer.
+static constexpr size_t kMetadataMsgQueueSize = 1 << 18 /* 256kB */;
+
+const int kBadFramesAfterStreamOn = 1;  // drop x frames after streamOn to get rid of some initial
+                                        // bad frames. TODO: develop a better bad frame detection
+                                        // method
+constexpr int MAX_RETRY = 15;  // Allow retry some ioctl failures a few times to account for some
+                               // webcam showing temporarily ioctl failures.
+constexpr int IOCTL_RETRY_SLEEP_US = 33000;  // 33ms * MAX_RETRY = 0.5 seconds
+
+// Constants for tryLock during dumpstate
+static constexpr int kDumpLockRetries = 50;
+static constexpr int kDumpLockSleep = 60000;
+
+bool tryLock(Mutex& mutex) {
+    bool locked = false;
+    for (int i = 0; i < kDumpLockRetries; ++i) {
+        if (mutex.tryLock() == NO_ERROR) {
+            locked = true;
+            break;
+        }
+        usleep(kDumpLockSleep);
+    }
+    return locked;
+}
+
+bool tryLock(std::mutex& mutex) {
+    bool locked = false;
+    for (int i = 0; i < kDumpLockRetries; ++i) {
+        if (mutex.try_lock()) {
+            locked = true;
+            break;
+        }
+        usleep(kDumpLockSleep);
+    }
+    return locked;
+}
+
+}  // anonymous namespace
+
+using ::aidl::android::hardware::camera::device::BufferRequestStatus;
+using ::aidl::android::hardware::camera::device::CameraBlob;
+using ::aidl::android::hardware::camera::device::CameraBlobId;
+using ::aidl::android::hardware::camera::device::ErrorMsg;
+using ::aidl::android::hardware::camera::device::ShutterMsg;
+using ::aidl::android::hardware::camera::device::StreamBuffer;
+using ::aidl::android::hardware::camera::device::StreamBufferRet;
+using ::aidl::android::hardware::camera::device::StreamBuffersVal;
+using ::aidl::android::hardware::camera::device::StreamConfigurationMode;
+using ::aidl::android::hardware::camera::device::StreamRotation;
+using ::aidl::android::hardware::camera::device::StreamType;
+using ::aidl::android::hardware::graphics::common::Dataspace;
+using ::android::hardware::camera::common::V1_0::helper::ExifUtils;
+
+// Static instances
+const int ExternalCameraDeviceSession::kMaxProcessedStream;
+const int ExternalCameraDeviceSession::kMaxStallStream;
+HandleImporter ExternalCameraDeviceSession::sHandleImporter;
+
+ExternalCameraDeviceSession::ExternalCameraDeviceSession(
+        const std::shared_ptr<ICameraDeviceCallback>& callback, const ExternalCameraConfig& cfg,
+        const std::vector<SupportedV4L2Format>& sortedFormats, const CroppingType& croppingType,
+        const common::V1_0::helper::CameraMetadata& chars, const std::string& cameraId,
+        unique_fd v4l2Fd)
+    : mCallback(callback),
+      mCfg(cfg),
+      mCameraCharacteristics(chars),
+      mSupportedFormats(sortedFormats),
+      mCroppingType(croppingType),
+      mCameraId(cameraId),
+      mV4l2Fd(std::move(v4l2Fd)),
+      mMaxThumbResolution(getMaxThumbResolution()),
+      mMaxJpegResolution(getMaxJpegResolution()) {}
+
+Size ExternalCameraDeviceSession::getMaxThumbResolution() const {
+    return getMaxThumbnailResolution(mCameraCharacteristics);
+}
+
+Size ExternalCameraDeviceSession::getMaxJpegResolution() const {
+    Size ret{0, 0};
+    for (auto& fmt : mSupportedFormats) {
+        if (fmt.width * fmt.height > ret.width * ret.height) {
+            ret = Size{fmt.width, fmt.height};
+        }
+    }
+    return ret;
+}
+
+bool ExternalCameraDeviceSession::initialize() {
+    if (mV4l2Fd.get() < 0) {
+        ALOGE("%s: invalid v4l2 device fd %d!", __FUNCTION__, mV4l2Fd.get());
+        return true;
+    }
+
+    struct v4l2_capability capability;
+    int ret = ioctl(mV4l2Fd.get(), VIDIOC_QUERYCAP, &capability);
+    std::string make, model;
+    if (ret < 0) {
+        ALOGW("%s v4l2 QUERYCAP failed", __FUNCTION__);
+        mExifMake = "Generic UVC webcam";
+        mExifModel = "Generic UVC webcam";
+    } else {
+        // capability.card is UTF-8 encoded
+        char card[32];
+        int j = 0;
+        for (int i = 0; i < 32; i++) {
+            if (capability.card[i] < 128) {
+                card[j++] = capability.card[i];
+            }
+            if (capability.card[i] == '\0') {
+                break;
+            }
+        }
+        if (j == 0 || card[j - 1] != '\0') {
+            mExifMake = "Generic UVC webcam";
+            mExifModel = "Generic UVC webcam";
+        } else {
+            mExifMake = card;
+            mExifModel = card;
+        }
+    }
+
+    initOutputThread();
+    if (mOutputThread == nullptr) {
+        ALOGE("%s: init OutputThread failed!", __FUNCTION__);
+        return true;
+    }
+    mOutputThread->setExifMakeModel(mExifMake, mExifModel);
+
+    status_t status = initDefaultRequests();
+    if (status != OK) {
+        ALOGE("%s: init default requests failed!", __FUNCTION__);
+        return true;
+    }
+
+    mRequestMetadataQueue =
+            std::make_unique<RequestMetadataQueue>(kMetadataMsgQueueSize, false /* non blocking */);
+    if (!mRequestMetadataQueue->isValid()) {
+        ALOGE("%s: invalid request fmq", __FUNCTION__);
+        return true;
+    }
+
+    mResultMetadataQueue =
+            std::make_shared<ResultMetadataQueue>(kMetadataMsgQueueSize, false /* non blocking */);
+    if (!mResultMetadataQueue->isValid()) {
+        ALOGE("%s: invalid result fmq", __FUNCTION__);
+        return true;
+    }
+
+    mOutputThread->run();
+    return false;
+}
+
+bool ExternalCameraDeviceSession::isInitFailed() {
+    Mutex::Autolock _l(mLock);
+    if (!mInitialized) {
+        mInitFail = initialize();
+        mInitialized = true;
+    }
+    return mInitFail;
+}
+
+void ExternalCameraDeviceSession::initOutputThread() {
+    // Grab a shared_ptr to 'this' from ndk::SharedRefBase::ref()
+    std::shared_ptr<ExternalCameraDeviceSession> thiz = ref<ExternalCameraDeviceSession>();
+
+    if (mSupportBufMgr) {
+        mBufferRequestThread = std::make_shared<BufferRequestThread>(/*parent=*/thiz, mCallback);
+        mBufferRequestThread->run();
+    }
+    mOutputThread = std::make_shared<OutputThread>(/*parent=*/thiz, mCroppingType,
+                                                   mCameraCharacteristics, mBufferRequestThread);
+}
+
+void ExternalCameraDeviceSession::closeOutputThread() {
+    closeOutputThreadImpl();
+}
+
+void ExternalCameraDeviceSession::closeOutputThreadImpl() {
+    if (mOutputThread != nullptr) {
+        mOutputThread->flush();
+        mOutputThread->requestExitAndWait();
+        mOutputThread.reset();
+    }
+}
+
+Status ExternalCameraDeviceSession::initStatus() const {
+    Mutex::Autolock _l(mLock);
+    Status status = Status::OK;
+    if (mInitFail || mClosed) {
+        ALOGI("%s: session initFailed %d closed %d", __FUNCTION__, mInitFail, mClosed);
+        status = Status::INTERNAL_ERROR;
+    }
+    return status;
+}
+
+ExternalCameraDeviceSession::~ExternalCameraDeviceSession() {
+    if (!isClosed()) {
+        ALOGE("ExternalCameraDeviceSession deleted before close!");
+        close(/*callerIsDtor*/ true);
+    }
+}
+
+ScopedAStatus ExternalCameraDeviceSession::constructDefaultRequestSettings(
+        RequestTemplate in_type, CameraMetadata* _aidl_return) {
+    CameraMetadata emptyMetadata;
+    Status status = initStatus();
+    if (status != Status::OK) {
+        return fromStatus(status);
+    }
+    switch (in_type) {
+        case RequestTemplate::PREVIEW:
+        case RequestTemplate::STILL_CAPTURE:
+        case RequestTemplate::VIDEO_RECORD:
+        case RequestTemplate::VIDEO_SNAPSHOT: {
+            *_aidl_return = mDefaultRequests[in_type];
+            break;
+        }
+        case RequestTemplate::MANUAL:
+        case RequestTemplate::ZERO_SHUTTER_LAG:
+            // Don't support MANUAL, ZSL templates
+            status = Status::ILLEGAL_ARGUMENT;
+            break;
+        default:
+            ALOGE("%s: unknown request template type %d", __FUNCTION__, static_cast<int>(in_type));
+            status = Status::ILLEGAL_ARGUMENT;
+            break;
+    }
+    return fromStatus(status);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::configureStreams(
+        const StreamConfiguration& in_requestedConfiguration,
+        std::vector<HalStream>* _aidl_return) {
+    uint32_t blobBufferSize = 0;
+    _aidl_return->clear();
+    Mutex::Autolock _il(mInterfaceLock);
+
+    Status status =
+            isStreamCombinationSupported(in_requestedConfiguration, mSupportedFormats, mCfg);
+    if (status != Status::OK) {
+        return fromStatus(status);
+    }
+
+    status = initStatus();
+    if (status != Status::OK) {
+        return fromStatus(status);
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(mInflightFramesLock);
+        if (!mInflightFrames.empty()) {
+            ALOGE("%s: trying to configureStreams while there are still %zu inflight frames!",
+                  __FUNCTION__, mInflightFrames.size());
+            return fromStatus(Status::INTERNAL_ERROR);
+        }
+    }
+
+    Mutex::Autolock _l(mLock);
+    {
+        Mutex::Autolock _cl(mCbsLock);
+        // Add new streams
+        for (const auto& stream : in_requestedConfiguration.streams) {
+            if (mStreamMap.count(stream.id) == 0) {
+                mStreamMap[stream.id] = stream;
+                mCirculatingBuffers.emplace(stream.id, CirculatingBuffers{});
+            }
+        }
+
+        // Cleanup removed streams
+        for (auto it = mStreamMap.begin(); it != mStreamMap.end();) {
+            int id = it->first;
+            bool found = false;
+            for (const auto& stream : in_requestedConfiguration.streams) {
+                if (id == stream.id) {
+                    found = true;
+                    break;
+                }
+            }
+            if (!found) {
+                // Unmap all buffers of deleted stream
+                cleanupBuffersLocked(id);
+                it = mStreamMap.erase(it);
+            } else {
+                ++it;
+            }
+        }
+    }
+
+    // Now select a V4L2 format to produce all output streams
+    float desiredAr = (mCroppingType == VERTICAL) ? kMaxAspectRatio : kMinAspectRatio;
+    uint32_t maxDim = 0;
+    for (const auto& stream : in_requestedConfiguration.streams) {
+        float aspectRatio = ASPECT_RATIO(stream);
+        ALOGI("%s: request stream %dx%d", __FUNCTION__, stream.width, stream.height);
+        if ((mCroppingType == VERTICAL && aspectRatio < desiredAr) ||
+            (mCroppingType == HORIZONTAL && aspectRatio > desiredAr)) {
+            desiredAr = aspectRatio;
+        }
+
+        // The dimension that's not cropped
+        uint32_t dim = (mCroppingType == VERTICAL) ? stream.width : stream.height;
+        if (dim > maxDim) {
+            maxDim = dim;
+        }
+    }
+
+    // Find the smallest format that matches the desired aspect ratio and is wide/high enough
+    SupportedV4L2Format v4l2Fmt{.width = 0, .height = 0};
+    for (const auto& fmt : mSupportedFormats) {
+        uint32_t dim = (mCroppingType == VERTICAL) ? fmt.width : fmt.height;
+        if (dim >= maxDim) {
+            float aspectRatio = ASPECT_RATIO(fmt);
+            if (isAspectRatioClose(aspectRatio, desiredAr)) {
+                v4l2Fmt = fmt;
+                // since mSupportedFormats is sorted by width then height, the first matching fmt
+                // will be the smallest one with matching aspect ratio
+                break;
+            }
+        }
+    }
+
+    if (v4l2Fmt.width == 0) {
+        // Cannot find exact good aspect ratio candidate, try to find a close one
+        for (const auto& fmt : mSupportedFormats) {
+            uint32_t dim = (mCroppingType == VERTICAL) ? fmt.width : fmt.height;
+            if (dim >= maxDim) {
+                float aspectRatio = ASPECT_RATIO(fmt);
+                if ((mCroppingType == VERTICAL && aspectRatio < desiredAr) ||
+                    (mCroppingType == HORIZONTAL && aspectRatio > desiredAr)) {
+                    v4l2Fmt = fmt;
+                    break;
+                }
+            }
+        }
+    }
+
+    if (v4l2Fmt.width == 0) {
+        ALOGE("%s: unable to find a resolution matching (%s at least %d, aspect ratio %f)",
+              __FUNCTION__, (mCroppingType == VERTICAL) ? "width" : "height", maxDim, desiredAr);
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    if (configureV4l2StreamLocked(v4l2Fmt) != 0) {
+        ALOGE("V4L configuration failed!, format:%c%c%c%c, w %d, h %d", v4l2Fmt.fourcc & 0xFF,
+              (v4l2Fmt.fourcc >> 8) & 0xFF, (v4l2Fmt.fourcc >> 16) & 0xFF,
+              (v4l2Fmt.fourcc >> 24) & 0xFF, v4l2Fmt.width, v4l2Fmt.height);
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    Size v4lSize = {v4l2Fmt.width, v4l2Fmt.height};
+    Size thumbSize{0, 0};
+    camera_metadata_ro_entry entry =
+            mCameraCharacteristics.find(ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES);
+    for (uint32_t i = 0; i < entry.count; i += 2) {
+        Size sz{entry.data.i32[i], entry.data.i32[i + 1]};
+        if (sz.width * sz.height > thumbSize.width * thumbSize.height) {
+            thumbSize = sz;
+        }
+    }
+
+    if (thumbSize.width * thumbSize.height == 0) {
+        ALOGE("%s: non-zero thumbnail size not available", __FUNCTION__);
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    mBlobBufferSize = blobBufferSize;
+    status = mOutputThread->allocateIntermediateBuffers(
+            v4lSize, mMaxThumbResolution, in_requestedConfiguration.streams, blobBufferSize);
+    if (status != Status::OK) {
+        ALOGE("%s: allocating intermediate buffers failed!", __FUNCTION__);
+        return fromStatus(status);
+    }
+
+    std::vector<HalStream>& out = *_aidl_return;
+    out.resize(in_requestedConfiguration.streams.size());
+    for (size_t i = 0; i < in_requestedConfiguration.streams.size(); i++) {
+        out[i].overrideDataSpace = in_requestedConfiguration.streams[i].dataSpace;
+        out[i].id = in_requestedConfiguration.streams[i].id;
+        // TODO: double check should we add those CAMERA flags
+        mStreamMap[in_requestedConfiguration.streams[i].id].usage = out[i].producerUsage =
+                static_cast<BufferUsage>(((int64_t)in_requestedConfiguration.streams[i].usage) |
+                                         ((int64_t)BufferUsage::CPU_WRITE_OFTEN) |
+                                         ((int64_t)BufferUsage::CAMERA_OUTPUT));
+        out[i].consumerUsage = static_cast<BufferUsage>(0);
+        out[i].maxBuffers = static_cast<int32_t>(mV4L2BufferCount);
+
+        switch (in_requestedConfiguration.streams[i].format) {
+            case PixelFormat::BLOB:
+            case PixelFormat::YCBCR_420_888:
+            case PixelFormat::YV12:  // Used by SurfaceTexture
+            case PixelFormat::Y16:
+                // No override
+                out[i].overrideFormat = in_requestedConfiguration.streams[i].format;
+                break;
+            case PixelFormat::IMPLEMENTATION_DEFINED:
+                // Implementation Defined
+                // This should look at the Stream's dataspace flag to determine the format or leave
+                // it as is if the rest of the system knows how to handle a private format. To keep
+                // this HAL generic, this is being overridden to YUV420
+                out[i].overrideFormat = PixelFormat::YCBCR_420_888;
+                // Save overridden format in mStreamMap
+                mStreamMap[in_requestedConfiguration.streams[i].id].format = out[i].overrideFormat;
+                break;
+            default:
+                ALOGE("%s: unsupported format 0x%x", __FUNCTION__,
+                      in_requestedConfiguration.streams[i].format);
+                return fromStatus(Status::ILLEGAL_ARGUMENT);
+        }
+    }
+
+    mFirstRequest = true;
+    mLastStreamConfigCounter = in_requestedConfiguration.streamConfigCounter;
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::flush() {
+    ATRACE_CALL();
+    Mutex::Autolock _il(mInterfaceLock);
+    Status status = initStatus();
+    if (status != Status::OK) {
+        return fromStatus(status);
+    }
+    mOutputThread->flush();
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::getCaptureRequestMetadataQueue(
+        MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) {
+    Mutex::Autolock _il(mInterfaceLock);
+    *_aidl_return = mRequestMetadataQueue->dupeDesc();
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::getCaptureResultMetadataQueue(
+        MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) {
+    Mutex::Autolock _il(mInterfaceLock);
+    *_aidl_return = mResultMetadataQueue->dupeDesc();
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::isReconfigurationRequired(
+        const CameraMetadata& in_oldSessionParams, const CameraMetadata& in_newSessionParams,
+        bool* _aidl_return) {
+    // reconfiguration required if there is any change in the session params
+    *_aidl_return = in_oldSessionParams != in_newSessionParams;
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::processCaptureRequest(
+        const std::vector<CaptureRequest>& in_requests,
+        const std::vector<BufferCache>& in_cachesToRemove, int32_t* _aidl_return) {
+    Mutex::Autolock _il(mInterfaceLock);
+    updateBufferCaches(in_cachesToRemove);
+
+    int32_t& numRequestProcessed = *_aidl_return;
+    numRequestProcessed = 0;
+    Status s = Status::OK;
+    for (size_t i = 0; i < in_requests.size(); i++, numRequestProcessed++) {
+        s = processOneCaptureRequest(in_requests[i]);
+        if (s != Status::OK) {
+            break;
+        }
+    }
+
+    return fromStatus(s);
+}
+
+Status ExternalCameraDeviceSession::processOneCaptureRequest(const CaptureRequest& request) {
+    ATRACE_CALL();
+    Status status = initStatus();
+    if (status != Status::OK) {
+        return status;
+    }
+
+    if (request.inputBuffer.streamId != -1) {
+        ALOGE("%s: external camera does not support reprocessing!", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    Mutex::Autolock _l(mLock);
+    if (!mV4l2Streaming) {
+        ALOGE("%s: cannot process request in streamOff state!", __FUNCTION__);
+        return Status::INTERNAL_ERROR;
+    }
+
+    const camera_metadata_t* rawSettings = nullptr;
+    bool converted;
+    CameraMetadata settingsFmq;  // settings from FMQ
+
+    if (request.fmqSettingsSize > 0) {
+        // non-blocking read; client must write metadata before calling
+        // processOneCaptureRequest
+        settingsFmq.metadata.resize(request.fmqSettingsSize);
+        bool read = mRequestMetadataQueue->read(
+                reinterpret_cast<int8_t*>(settingsFmq.metadata.data()), request.fmqSettingsSize);
+        if (read) {
+            converted = convertFromAidl(settingsFmq, &rawSettings);
+        } else {
+            ALOGE("%s: capture request settings metadata couldn't be read from fmq!", __FUNCTION__);
+            converted = false;
+        }
+    } else {
+        converted = convertFromAidl(request.settings, &rawSettings);
+    }
+
+    if (converted && rawSettings != nullptr) {
+        mLatestReqSetting = rawSettings;
+    }
+
+    if (!converted) {
+        ALOGE("%s: capture request settings metadata is corrupt!", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    if (mFirstRequest && rawSettings == nullptr) {
+        ALOGE("%s: capture request settings must not be null for first request!", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    std::vector<buffer_handle_t*> allBufPtrs;
+    std::vector<int> allFences;
+    size_t numOutputBufs = request.outputBuffers.size();
+
+    if (numOutputBufs == 0) {
+        ALOGE("%s: capture request must have at least one output buffer!", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    camera_metadata_entry fpsRange = mLatestReqSetting.find(ANDROID_CONTROL_AE_TARGET_FPS_RANGE);
+    if (fpsRange.count == 2) {
+        double requestFpsMax = fpsRange.data.i32[1];
+        double closestFps = 0.0;
+        double fpsError = 1000.0;
+        bool fpsSupported = false;
+        for (const auto& fr : mV4l2StreamingFmt.frameRates) {
+            double f = fr.getFramesPerSecond();
+            if (std::fabs(requestFpsMax - f) < 1.0) {
+                fpsSupported = true;
+                break;
+            }
+            if (std::fabs(requestFpsMax - f) < fpsError) {
+                fpsError = std::fabs(requestFpsMax - f);
+                closestFps = f;
+            }
+        }
+        if (!fpsSupported) {
+            /* This can happen in a few scenarios:
+             * 1. The application is sending an FPS range not supported by the configured outputs.
+             * 2. The application is sending a valid FPS range for all configured outputs, but
+             *    the selected V4L2 size can only run at slower speed. This should be very rare
+             *    though: for this to happen a sensor needs to support at least 3 different aspect
+             *    ratio outputs, and when (at least) two outputs are both not the main aspect ratio
+             *    of the webcam, a third size that's larger might be picked and runs into this
+             *    issue.
+             */
+            ALOGW("%s: cannot reach fps %d! Will do %f instead", __FUNCTION__, fpsRange.data.i32[1],
+                  closestFps);
+            requestFpsMax = closestFps;
+        }
+
+        if (requestFpsMax != mV4l2StreamingFps) {
+            {
+                std::unique_lock<std::mutex> lk(mV4l2BufferLock);
+                while (mNumDequeuedV4l2Buffers != 0) {
+                    // Wait until pipeline is idle before reconfigure stream
+                    int waitRet = waitForV4L2BufferReturnLocked(lk);
+                    if (waitRet != 0) {
+                        ALOGE("%s: wait for pipeline idle failed!", __FUNCTION__);
+                        return Status::INTERNAL_ERROR;
+                    }
+                }
+            }
+            configureV4l2StreamLocked(mV4l2StreamingFmt, requestFpsMax);
+        }
+    }
+
+    status = importRequestLocked(request, allBufPtrs, allFences);
+    if (status != Status::OK) {
+        return status;
+    }
+
+    nsecs_t shutterTs = 0;
+    std::unique_ptr<V4L2Frame> frameIn = dequeueV4l2FrameLocked(&shutterTs);
+    if (frameIn == nullptr) {
+        ALOGE("%s: V4L2 deque frame failed!", __FUNCTION__);
+        return Status::INTERNAL_ERROR;
+    }
+
+    std::shared_ptr<HalRequest> halReq = std::make_shared<HalRequest>();
+    halReq->frameNumber = request.frameNumber;
+    halReq->setting = mLatestReqSetting;
+    halReq->frameIn = std::move(frameIn);
+    halReq->shutterTs = shutterTs;
+    halReq->buffers.resize(numOutputBufs);
+    for (size_t i = 0; i < numOutputBufs; i++) {
+        HalStreamBuffer& halBuf = halReq->buffers[i];
+        int streamId = halBuf.streamId = request.outputBuffers[i].streamId;
+        halBuf.bufferId = request.outputBuffers[i].bufferId;
+        const Stream& stream = mStreamMap[streamId];
+        halBuf.width = stream.width;
+        halBuf.height = stream.height;
+        halBuf.format = stream.format;
+        halBuf.usage = stream.usage;
+        halBuf.bufPtr = allBufPtrs[i];
+        halBuf.acquireFence = allFences[i];
+        halBuf.fenceTimeout = false;
+    }
+    {
+        std::lock_guard<std::mutex> lk(mInflightFramesLock);
+        mInflightFrames.insert(halReq->frameNumber);
+    }
+    // Send request to OutputThread for the rest of processing
+    mOutputThread->submitRequest(halReq);
+    mFirstRequest = false;
+    return Status::OK;
+}
+
+ScopedAStatus ExternalCameraDeviceSession::signalStreamFlush(
+        const std::vector<int32_t>& /*in_streamIds*/, int32_t in_streamConfigCounter) {
+    {
+        Mutex::Autolock _l(mLock);
+        if (in_streamConfigCounter < mLastStreamConfigCounter) {
+            // stale call. new streams have been configured since this call was issued.
+            // Do nothing.
+            return fromStatus(Status::OK);
+        }
+    }
+
+    // TODO: implement if needed.
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::switchToOffline(
+        const std::vector<int32_t>& in_streamsToKeep,
+        CameraOfflineSessionInfo* out_offlineSessionInfo,
+        std::shared_ptr<ICameraOfflineSession>* _aidl_return) {
+    std::vector<NotifyMsg> msgs;
+    std::vector<CaptureResult> results;
+    CameraOfflineSessionInfo info;
+    std::shared_ptr<ICameraOfflineSession> session;
+    Status st = switchToOffline(in_streamsToKeep, &msgs, &results, &info, &session);
+
+    mCallback->notify(msgs);
+    invokeProcessCaptureResultCallback(results, /* tryWriteFmq= */ true);
+    freeReleaseFences(results);
+
+    // setup return values
+    *out_offlineSessionInfo = info;
+    *_aidl_return = session;
+    return fromStatus(st);
+}
+
+Status ExternalCameraDeviceSession::switchToOffline(
+        const std::vector<int32_t>& offlineStreams, std::vector<NotifyMsg>* msgs,
+        std::vector<CaptureResult>* results, CameraOfflineSessionInfo* info,
+        std::shared_ptr<ICameraOfflineSession>* session) {
+    ATRACE_CALL();
+    if (offlineStreams.size() > 1) {
+        ALOGE("%s: more than one offline stream is not supported", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    if (info == nullptr || results == nullptr || info == nullptr || session == nullptr) {
+        ALOGE("%s, output arguments (%p, %p, %p, %p) much not be null", __FUNCTION__, msgs, results,
+              info, session);
+    }
+
+    Mutex::Autolock _il(mInterfaceLock);
+    Status status = initStatus();
+    if (status != Status::OK) {
+        return status;
+    }
+
+    Mutex::Autolock _l(mLock);
+    for (auto streamId : offlineStreams) {
+        if (!supportOfflineLocked(streamId)) {
+            return Status::ILLEGAL_ARGUMENT;
+        }
+    }
+
+    // pause output thread and get all remaining inflight requests
+    auto remainingReqs = mOutputThread->switchToOffline();
+    std::vector<std::shared_ptr<HalRequest>> halReqs;
+
+    // Send out buffer/request error for remaining requests and filter requests
+    // to be handled in offline mode
+    for (auto& halReq : remainingReqs) {
+        bool dropReq = canDropRequest(offlineStreams, halReq);
+        if (dropReq) {
+            // Request is dropped completely. Just send request error and
+            // there is no need to send the request to offline session
+            processCaptureRequestError(halReq, msgs, results);
+            continue;
+        }
+
+        // All requests reach here must have at least one offline stream output
+        NotifyMsg shutter;
+        aidl::android::hardware::camera::device::ShutterMsg shutterMsg = {
+                .frameNumber = static_cast<int32_t>(halReq->frameNumber),
+                .timestamp = halReq->shutterTs};
+        shutter.set<NotifyMsg::Tag::shutter>(shutterMsg);
+        msgs->push_back(shutter);
+
+        std::vector<HalStreamBuffer> offlineBuffers;
+        for (const auto& buffer : halReq->buffers) {
+            bool dropBuffer = true;
+            for (auto offlineStreamId : offlineStreams) {
+                if (buffer.streamId == offlineStreamId) {
+                    dropBuffer = false;
+                    break;
+                }
+            }
+            if (dropBuffer) {
+                aidl::android::hardware::camera::device::ErrorMsg errorMsg = {
+                        .frameNumber = static_cast<int32_t>(halReq->frameNumber),
+                        .errorStreamId = buffer.streamId,
+                        .errorCode = ErrorCode::ERROR_BUFFER};
+
+                NotifyMsg error;
+                error.set<NotifyMsg::Tag::error>(errorMsg);
+                msgs->push_back(error);
+
+                results->push_back({
+                        .frameNumber = static_cast<int32_t>(halReq->frameNumber),
+                        .outputBuffers = {},
+                        .inputBuffer = {.streamId = -1},
+                        .partialResult = 0,  // buffer only result
+                });
+
+                CaptureResult& result = results->back();
+                result.outputBuffers.resize(1);
+                StreamBuffer& outputBuffer = result.outputBuffers[0];
+                outputBuffer.streamId = buffer.streamId;
+                outputBuffer.bufferId = buffer.bufferId;
+                outputBuffer.status = BufferStatus::ERROR;
+                if (buffer.acquireFence >= 0) {
+                    native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+                    handle->data[0] = buffer.acquireFence;
+                    outputBuffer.releaseFence = android::makeToAidl(handle);
+                }
+            } else {
+                offlineBuffers.push_back(buffer);
+            }
+        }
+        halReq->buffers = offlineBuffers;
+        halReqs.push_back(halReq);
+    }
+
+    // convert hal requests to offline request
+    std::deque<std::shared_ptr<HalRequest>> offlineReqs(halReqs.size());
+    size_t i = 0;
+    for (auto& v4lReq : halReqs) {
+        offlineReqs[i] = std::make_shared<HalRequest>();
+        offlineReqs[i]->frameNumber = v4lReq->frameNumber;
+        offlineReqs[i]->setting = v4lReq->setting;
+        offlineReqs[i]->shutterTs = v4lReq->shutterTs;
+        offlineReqs[i]->buffers = v4lReq->buffers;
+        std::shared_ptr<V4L2Frame> v4l2Frame(static_cast<V4L2Frame*>(v4lReq->frameIn.get()));
+        offlineReqs[i]->frameIn = std::make_shared<AllocatedV4L2Frame>(v4l2Frame);
+        i++;
+        // enqueue V4L2 frame
+        enqueueV4l2Frame(v4l2Frame);
+    }
+
+    // Collect buffer caches/streams
+    std::vector<Stream> streamInfos(offlineStreams.size());
+    std::map<int, CirculatingBuffers> circulatingBuffers;
+    {
+        Mutex::Autolock _cbsl(mCbsLock);
+        for (auto streamId : offlineStreams) {
+            circulatingBuffers[streamId] = mCirculatingBuffers.at(streamId);
+            mCirculatingBuffers.erase(streamId);
+            streamInfos.push_back(mStreamMap.at(streamId));
+            mStreamMap.erase(streamId);
+        }
+    }
+
+    fillOfflineSessionInfo(offlineStreams, offlineReqs, circulatingBuffers, info);
+    // create the offline session object
+    bool afTrigger;
+    {
+        std::lock_guard<std::mutex> _lk(mAfTriggerLock);
+        afTrigger = mAfTrigger;
+    }
+
+    std::shared_ptr<ExternalCameraOfflineSession> sessionImpl =
+            ndk::SharedRefBase::make<ExternalCameraOfflineSession>(
+                    mCroppingType, mCameraCharacteristics, mCameraId, mExifMake, mExifModel,
+                    mBlobBufferSize, afTrigger, streamInfos, offlineReqs, circulatingBuffers);
+
+    bool initFailed = sessionImpl->initialize();
+    if (initFailed) {
+        ALOGE("%s: offline session initialize failed!", __FUNCTION__);
+        return Status::INTERNAL_ERROR;
+    }
+
+    // cleanup stream and buffer caches
+    {
+        Mutex::Autolock _cbsl(mCbsLock);
+        for (auto pair : mStreamMap) {
+            cleanupBuffersLocked(/*Stream ID*/ pair.first);
+        }
+        mCirculatingBuffers.clear();
+    }
+    mStreamMap.clear();
+
+    // update inflight records
+    {
+        std::lock_guard<std::mutex> _lk(mInflightFramesLock);
+        mInflightFrames.clear();
+    }
+
+    // stop v4l2 streaming
+    if (v4l2StreamOffLocked() != 0) {
+        ALOGE("%s: stop V4L2 streaming failed!", __FUNCTION__);
+        return Status::INTERNAL_ERROR;
+    }
+
+    // No need to return session if there is no offline requests left
+    if (!offlineReqs.empty()) {
+        *session = sessionImpl;
+    } else {
+        *session = nullptr;
+    }
+
+    return Status::OK;
+}
+
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
+#define UPDATE(md, tag, data, size)               \
+    do {                                          \
+        if ((md).update((tag), (data), (size))) { \
+            ALOGE("Update " #tag " failed!");     \
+            return BAD_VALUE;                     \
+        }                                         \
+    } while (0)
+
+status_t ExternalCameraDeviceSession::initDefaultRequests() {
+    common::V1_0::helper::CameraMetadata md;
+
+    const uint8_t aberrationMode = ANDROID_COLOR_CORRECTION_ABERRATION_MODE_OFF;
+    UPDATE(md, ANDROID_COLOR_CORRECTION_ABERRATION_MODE, &aberrationMode, 1);
+
+    const int32_t exposureCompensation = 0;
+    UPDATE(md, ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION, &exposureCompensation, 1);
+
+    const uint8_t videoStabilizationMode = ANDROID_CONTROL_VIDEO_STABILIZATION_MODE_OFF;
+    UPDATE(md, ANDROID_CONTROL_VIDEO_STABILIZATION_MODE, &videoStabilizationMode, 1);
+
+    const uint8_t awbMode = ANDROID_CONTROL_AWB_MODE_AUTO;
+    UPDATE(md, ANDROID_CONTROL_AWB_MODE, &awbMode, 1);
+
+    const uint8_t aeMode = ANDROID_CONTROL_AE_MODE_ON;
+    UPDATE(md, ANDROID_CONTROL_AE_MODE, &aeMode, 1);
+
+    const uint8_t aePrecaptureTrigger = ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER_IDLE;
+    UPDATE(md, ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER, &aePrecaptureTrigger, 1);
+
+    const uint8_t afMode = ANDROID_CONTROL_AF_MODE_AUTO;
+    UPDATE(md, ANDROID_CONTROL_AF_MODE, &afMode, 1);
+
+    const uint8_t afTrigger = ANDROID_CONTROL_AF_TRIGGER_IDLE;
+    UPDATE(md, ANDROID_CONTROL_AF_TRIGGER, &afTrigger, 1);
+
+    const uint8_t sceneMode = ANDROID_CONTROL_SCENE_MODE_DISABLED;
+    UPDATE(md, ANDROID_CONTROL_SCENE_MODE, &sceneMode, 1);
+
+    const uint8_t effectMode = ANDROID_CONTROL_EFFECT_MODE_OFF;
+    UPDATE(md, ANDROID_CONTROL_EFFECT_MODE, &effectMode, 1);
+
+    const uint8_t flashMode = ANDROID_FLASH_MODE_OFF;
+    UPDATE(md, ANDROID_FLASH_MODE, &flashMode, 1);
+
+    const int32_t thumbnailSize[] = {240, 180};
+    UPDATE(md, ANDROID_JPEG_THUMBNAIL_SIZE, thumbnailSize, 2);
+
+    const uint8_t jpegQuality = 90;
+    UPDATE(md, ANDROID_JPEG_QUALITY, &jpegQuality, 1);
+    UPDATE(md, ANDROID_JPEG_THUMBNAIL_QUALITY, &jpegQuality, 1);
+
+    const int32_t jpegOrientation = 0;
+    UPDATE(md, ANDROID_JPEG_ORIENTATION, &jpegOrientation, 1);
+
+    const uint8_t oisMode = ANDROID_LENS_OPTICAL_STABILIZATION_MODE_OFF;
+    UPDATE(md, ANDROID_LENS_OPTICAL_STABILIZATION_MODE, &oisMode, 1);
+
+    const uint8_t nrMode = ANDROID_NOISE_REDUCTION_MODE_OFF;
+    UPDATE(md, ANDROID_NOISE_REDUCTION_MODE, &nrMode, 1);
+
+    const int32_t testPatternModes = ANDROID_SENSOR_TEST_PATTERN_MODE_OFF;
+    UPDATE(md, ANDROID_SENSOR_TEST_PATTERN_MODE, &testPatternModes, 1);
+
+    const uint8_t fdMode = ANDROID_STATISTICS_FACE_DETECT_MODE_OFF;
+    UPDATE(md, ANDROID_STATISTICS_FACE_DETECT_MODE, &fdMode, 1);
+
+    const uint8_t hotpixelMode = ANDROID_STATISTICS_HOT_PIXEL_MAP_MODE_OFF;
+    UPDATE(md, ANDROID_STATISTICS_HOT_PIXEL_MAP_MODE, &hotpixelMode, 1);
+
+    bool support30Fps = false;
+    int32_t maxFps = std::numeric_limits<int32_t>::min();
+    for (const auto& supportedFormat : mSupportedFormats) {
+        for (const auto& fr : supportedFormat.frameRates) {
+            int32_t framerateInt = static_cast<int32_t>(fr.getFramesPerSecond());
+            if (maxFps < framerateInt) {
+                maxFps = framerateInt;
+            }
+            if (framerateInt == 30) {
+                support30Fps = true;
+                break;
+            }
+        }
+        if (support30Fps) {
+            break;
+        }
+    }
+
+    int32_t defaultFramerate = support30Fps ? 30 : maxFps;
+    int32_t defaultFpsRange[] = {defaultFramerate / 2, defaultFramerate};
+    UPDATE(md, ANDROID_CONTROL_AE_TARGET_FPS_RANGE, defaultFpsRange, ARRAY_SIZE(defaultFpsRange));
+
+    uint8_t antibandingMode = ANDROID_CONTROL_AE_ANTIBANDING_MODE_AUTO;
+    UPDATE(md, ANDROID_CONTROL_AE_ANTIBANDING_MODE, &antibandingMode, 1);
+
+    const uint8_t controlMode = ANDROID_CONTROL_MODE_AUTO;
+    UPDATE(md, ANDROID_CONTROL_MODE, &controlMode, 1);
+
+    for (const auto& type : ndk::enum_range<RequestTemplate>()) {
+        common::V1_0::helper::CameraMetadata mdCopy = md;
+        uint8_t intent = ANDROID_CONTROL_CAPTURE_INTENT_PREVIEW;
+        switch (type) {
+            case RequestTemplate::PREVIEW:
+                intent = ANDROID_CONTROL_CAPTURE_INTENT_PREVIEW;
+                break;
+            case RequestTemplate::STILL_CAPTURE:
+                intent = ANDROID_CONTROL_CAPTURE_INTENT_STILL_CAPTURE;
+                break;
+            case RequestTemplate::VIDEO_RECORD:
+                intent = ANDROID_CONTROL_CAPTURE_INTENT_VIDEO_RECORD;
+                break;
+            case RequestTemplate::VIDEO_SNAPSHOT:
+                intent = ANDROID_CONTROL_CAPTURE_INTENT_VIDEO_SNAPSHOT;
+                break;
+            default:
+                ALOGV("%s: unsupported RequestTemplate type %d", __FUNCTION__, type);
+                continue;
+        }
+        UPDATE(mdCopy, ANDROID_CONTROL_CAPTURE_INTENT, &intent, 1);
+        camera_metadata_t* mdPtr = mdCopy.release();
+        uint8_t* rawMd = reinterpret_cast<uint8_t*>(mdPtr);
+        CameraMetadata aidlMd;
+        aidlMd.metadata.assign(rawMd, rawMd + get_camera_metadata_size(mdPtr));
+        mDefaultRequests[type] = aidlMd;
+        free_camera_metadata(mdPtr);
+    }
+    return OK;
+}
+
+status_t ExternalCameraDeviceSession::fillCaptureResult(common::V1_0::helper::CameraMetadata& md,
+                                                        nsecs_t timestamp) {
+    bool afTrigger = false;
+    {
+        std::lock_guard<std::mutex> lk(mAfTriggerLock);
+        afTrigger = mAfTrigger;
+        if (md.exists(ANDROID_CONTROL_AF_TRIGGER)) {
+            camera_metadata_entry entry = md.find(ANDROID_CONTROL_AF_TRIGGER);
+            if (entry.data.u8[0] == ANDROID_CONTROL_AF_TRIGGER_START) {
+                mAfTrigger = afTrigger = true;
+            } else if (entry.data.u8[0] == ANDROID_CONTROL_AF_TRIGGER_CANCEL) {
+                mAfTrigger = afTrigger = false;
+            }
+        }
+    }
+
+    // For USB camera, the USB camera handles everything and we don't have control
+    // over AF. We only simply fake the AF metadata based on the request
+    // received here.
+    uint8_t afState;
+    if (afTrigger) {
+        afState = ANDROID_CONTROL_AF_STATE_FOCUSED_LOCKED;
+    } else {
+        afState = ANDROID_CONTROL_AF_STATE_INACTIVE;
+    }
+    UPDATE(md, ANDROID_CONTROL_AF_STATE, &afState, 1);
+
+    camera_metadata_ro_entry activeArraySize =
+            mCameraCharacteristics.find(ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE);
+
+    return fillCaptureResultCommon(md, timestamp, activeArraySize);
+}
+
+int ExternalCameraDeviceSession::configureV4l2StreamLocked(const SupportedV4L2Format& v4l2Fmt,
+                                                           double requestFps) {
+    ATRACE_CALL();
+    int ret = v4l2StreamOffLocked();
+    if (ret != OK) {
+        ALOGE("%s: stop v4l2 streaming failed: ret %d", __FUNCTION__, ret);
+        return ret;
+    }
+
+    // VIDIOC_S_FMT w/h/fmt
+    v4l2_format fmt;
+    fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    fmt.fmt.pix.width = v4l2Fmt.width;
+    fmt.fmt.pix.height = v4l2Fmt.height;
+    fmt.fmt.pix.pixelformat = v4l2Fmt.fourcc;
+
+    {
+        int numAttempt = 0;
+        do {
+            ret = TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_S_FMT, &fmt));
+            if (numAttempt == MAX_RETRY) {
+                break;
+            }
+            numAttempt++;
+            if (ret < 0) {
+                ALOGW("%s: VIDIOC_S_FMT failed, wait 33ms and try again", __FUNCTION__);
+                usleep(IOCTL_RETRY_SLEEP_US);  // sleep and try again
+            }
+        } while (ret < 0);
+        if (ret < 0) {
+            ALOGE("%s: S_FMT ioctl failed: %s", __FUNCTION__, strerror(errno));
+            return -errno;
+        }
+    }
+
+    if (v4l2Fmt.width != fmt.fmt.pix.width || v4l2Fmt.height != fmt.fmt.pix.height ||
+        v4l2Fmt.fourcc != fmt.fmt.pix.pixelformat) {
+        ALOGE("%s: S_FMT expect %c%c%c%c %dx%d, got %c%c%c%c %dx%d instead!", __FUNCTION__,
+              v4l2Fmt.fourcc & 0xFF, (v4l2Fmt.fourcc >> 8) & 0xFF, (v4l2Fmt.fourcc >> 16) & 0xFF,
+              (v4l2Fmt.fourcc >> 24) & 0xFF, v4l2Fmt.width, v4l2Fmt.height,
+              fmt.fmt.pix.pixelformat & 0xFF, (fmt.fmt.pix.pixelformat >> 8) & 0xFF,
+              (fmt.fmt.pix.pixelformat >> 16) & 0xFF, (fmt.fmt.pix.pixelformat >> 24) & 0xFF,
+              fmt.fmt.pix.width, fmt.fmt.pix.height);
+        return -EINVAL;
+    }
+
+    uint32_t bufferSize = fmt.fmt.pix.sizeimage;
+    ALOGI("%s: V4L2 buffer size is %d", __FUNCTION__, bufferSize);
+    uint32_t expectedMaxBufferSize = kMaxBytesPerPixel * fmt.fmt.pix.width * fmt.fmt.pix.height;
+    if ((bufferSize == 0) || (bufferSize > expectedMaxBufferSize)) {
+        ALOGE("%s: V4L2 buffer size: %u looks invalid. Expected maximum size: %u", __FUNCTION__,
+              bufferSize, expectedMaxBufferSize);
+        return -EINVAL;
+    }
+    mMaxV4L2BufferSize = bufferSize;
+
+    const double kDefaultFps = 30.0;
+    double fps = std::numeric_limits<double>::max();
+    if (requestFps != 0.0) {
+        fps = requestFps;
+    } else {
+        double maxFps = -1.0;
+        // Try to pick the slowest fps that is at least 30
+        for (const auto& fr : v4l2Fmt.frameRates) {
+            double f = fr.getFramesPerSecond();
+            if (maxFps < f) {
+                maxFps = f;
+            }
+            if (f >= kDefaultFps && f < fps) {
+                fps = f;
+            }
+        }
+        // No fps > 30 found, use the highest fps available within supported formats.
+        if (fps == std::numeric_limits<double>::max()) {
+            fps = maxFps;
+        }
+    }
+
+    int fpsRet = setV4l2FpsLocked(fps);
+    if (fpsRet != 0 && fpsRet != -EINVAL) {
+        ALOGE("%s: set fps failed: %s", __FUNCTION__, strerror(fpsRet));
+        return fpsRet;
+    }
+
+    uint32_t v4lBufferCount = (fps >= kDefaultFps) ? mCfg.numVideoBuffers : mCfg.numStillBuffers;
+
+    // VIDIOC_REQBUFS: create buffers
+    v4l2_requestbuffers req_buffers{};
+    req_buffers.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    req_buffers.memory = V4L2_MEMORY_MMAP;
+    req_buffers.count = v4lBufferCount;
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_REQBUFS, &req_buffers)) < 0) {
+        ALOGE("%s: VIDIOC_REQBUFS failed: %s", __FUNCTION__, strerror(errno));
+        return -errno;
+    }
+
+    // Driver can indeed return more buffer if it needs more to operate
+    if (req_buffers.count < v4lBufferCount) {
+        ALOGE("%s: VIDIOC_REQBUFS expected %d buffers, got %d instead", __FUNCTION__,
+              v4lBufferCount, req_buffers.count);
+        return NO_MEMORY;
+    }
+
+    // VIDIOC_QUERYBUF:  get buffer offset in the V4L2 fd
+    // VIDIOC_QBUF: send buffer to driver
+    mV4L2BufferCount = req_buffers.count;
+    for (uint32_t i = 0; i < req_buffers.count; i++) {
+        v4l2_buffer buffer = {
+                .index = i, .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, .memory = V4L2_MEMORY_MMAP};
+
+        if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_QUERYBUF, &buffer)) < 0) {
+            ALOGE("%s: QUERYBUF %d failed: %s", __FUNCTION__, i, strerror(errno));
+            return -errno;
+        }
+
+        if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_QBUF, &buffer)) < 0) {
+            ALOGE("%s: QBUF %d failed: %s", __FUNCTION__, i, strerror(errno));
+            return -errno;
+        }
+    }
+
+    {
+        // VIDIOC_STREAMON: start streaming
+        v4l2_buf_type capture_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        int numAttempt = 0;
+        do {
+            ret = TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_STREAMON, &capture_type));
+            if (numAttempt == MAX_RETRY) {
+                break;
+            }
+            if (ret < 0) {
+                ALOGW("%s: VIDIOC_STREAMON failed, wait 33ms and try again", __FUNCTION__);
+                usleep(IOCTL_RETRY_SLEEP_US);  // sleep 100 ms and try again
+            }
+        } while (ret < 0);
+
+        if (ret < 0) {
+            ALOGE("%s: VIDIOC_STREAMON ioctl failed: %s", __FUNCTION__, strerror(errno));
+            return -errno;
+        }
+    }
+
+    // Swallow first few frames after streamOn to account for bad frames from some devices
+    for (int i = 0; i < kBadFramesAfterStreamOn; i++) {
+        v4l2_buffer buffer{};
+        buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+        buffer.memory = V4L2_MEMORY_MMAP;
+        if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_DQBUF, &buffer)) < 0) {
+            ALOGE("%s: DQBUF fails: %s", __FUNCTION__, strerror(errno));
+            return -errno;
+        }
+
+        if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_QBUF, &buffer)) < 0) {
+            ALOGE("%s: QBUF index %d fails: %s", __FUNCTION__, buffer.index, strerror(errno));
+            return -errno;
+        }
+    }
+
+    ALOGI("%s: start V4L2 streaming %dx%d@%ffps", __FUNCTION__, v4l2Fmt.width, v4l2Fmt.height, fps);
+    mV4l2StreamingFmt = v4l2Fmt;
+    mV4l2Streaming = true;
+    return OK;
+}
+
+std::unique_ptr<V4L2Frame> ExternalCameraDeviceSession::dequeueV4l2FrameLocked(nsecs_t* shutterTs) {
+    ATRACE_CALL();
+    std::unique_ptr<V4L2Frame> ret = nullptr;
+    if (shutterTs == nullptr) {
+        ALOGE("%s: shutterTs must not be null!", __FUNCTION__);
+        return ret;
+    }
+
+    {
+        std::unique_lock<std::mutex> lk(mV4l2BufferLock);
+        if (mNumDequeuedV4l2Buffers == mV4L2BufferCount) {
+            int waitRet = waitForV4L2BufferReturnLocked(lk);
+            if (waitRet != 0) {
+                return ret;
+            }
+        }
+    }
+
+    ATRACE_BEGIN("VIDIOC_DQBUF");
+    v4l2_buffer buffer{};
+    buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    buffer.memory = V4L2_MEMORY_MMAP;
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_DQBUF, &buffer)) < 0) {
+        ALOGE("%s: DQBUF fails: %s", __FUNCTION__, strerror(errno));
+        return ret;
+    }
+    ATRACE_END();
+
+    if (buffer.index >= mV4L2BufferCount) {
+        ALOGE("%s: Invalid buffer id: %d", __FUNCTION__, buffer.index);
+        return ret;
+    }
+
+    if (buffer.flags & V4L2_BUF_FLAG_ERROR) {
+        ALOGE("%s: v4l2 buf error! buf flag 0x%x", __FUNCTION__, buffer.flags);
+        // TODO: try to dequeue again
+    }
+
+    if (buffer.bytesused > mMaxV4L2BufferSize) {
+        ALOGE("%s: v4l2 buffer bytes used: %u maximum %u", __FUNCTION__, buffer.bytesused,
+              mMaxV4L2BufferSize);
+        return ret;
+    }
+
+    if (buffer.flags & V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC) {
+        // Ideally we should also check for V4L2_BUF_FLAG_TSTAMP_SRC_SOE, but
+        // even V4L2_BUF_FLAG_TSTAMP_SRC_EOF is better than capture a timestamp now
+        *shutterTs = static_cast<nsecs_t>(buffer.timestamp.tv_sec) * 1000000000LL +
+                     buffer.timestamp.tv_usec * 1000LL;
+    } else {
+        *shutterTs = systemTime(SYSTEM_TIME_MONOTONIC);
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(mV4l2BufferLock);
+        mNumDequeuedV4l2Buffers++;
+    }
+
+    return std::make_unique<V4L2Frame>(mV4l2StreamingFmt.width, mV4l2StreamingFmt.height,
+                                       mV4l2StreamingFmt.fourcc, buffer.index, mV4l2Fd.get(),
+                                       buffer.bytesused, buffer.m.offset);
+}
+
+void ExternalCameraDeviceSession::enqueueV4l2Frame(const std::shared_ptr<V4L2Frame>& frame) {
+    ATRACE_CALL();
+    frame->unmap();
+    ATRACE_BEGIN("VIDIOC_QBUF");
+    v4l2_buffer buffer{};
+    buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    buffer.memory = V4L2_MEMORY_MMAP;
+    buffer.index = frame->mBufferIndex;
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_QBUF, &buffer)) < 0) {
+        ALOGE("%s: QBUF index %d fails: %s", __FUNCTION__, frame->mBufferIndex, strerror(errno));
+        return;
+    }
+    ATRACE_END();
+
+    {
+        std::lock_guard<std::mutex> lk(mV4l2BufferLock);
+        mNumDequeuedV4l2Buffers--;
+    }
+    mV4L2BufferReturned.notify_one();
+}
+
+bool ExternalCameraDeviceSession::isSupported(
+        const Stream& stream, const std::vector<SupportedV4L2Format>& supportedFormats,
+        const ExternalCameraConfig& devCfg) {
+    Dataspace ds = stream.dataSpace;
+    PixelFormat fmt = stream.format;
+    uint32_t width = stream.width;
+    uint32_t height = stream.height;
+    // TODO: check usage flags
+
+    if (stream.streamType != StreamType::OUTPUT) {
+        ALOGE("%s: does not support non-output stream type", __FUNCTION__);
+        return false;
+    }
+
+    if (stream.rotation != StreamRotation::ROTATION_0) {
+        ALOGE("%s: does not support stream rotation", __FUNCTION__);
+        return false;
+    }
+
+    switch (fmt) {
+        case PixelFormat::BLOB:
+            if (ds != Dataspace::JFIF) {
+                ALOGI("%s: BLOB format does not support dataSpace %x", __FUNCTION__, ds);
+                return false;
+            }
+            break;
+        case PixelFormat::IMPLEMENTATION_DEFINED:
+        case PixelFormat::YCBCR_420_888:
+        case PixelFormat::YV12:
+            // TODO: check what dataspace we can support here.
+            // intentional no-ops.
+            break;
+        case PixelFormat::Y16:
+            if (!devCfg.depthEnabled) {
+                ALOGI("%s: Depth is not Enabled", __FUNCTION__);
+                return false;
+            }
+            if (!(static_cast<int32_t>(ds) & static_cast<int32_t>(Dataspace::DEPTH))) {
+                ALOGI("%s: Y16 supports only dataSpace DEPTH", __FUNCTION__);
+                return false;
+            }
+            break;
+        default:
+            ALOGI("%s: does not support format %x", __FUNCTION__, fmt);
+            return false;
+    }
+
+    // Assume we can convert any V4L2 format to any of supported output format for now, i.e.
+    // ignoring v4l2Fmt.fourcc for now. Might need more subtle check if we support more v4l format
+    // in the futrue.
+    for (const auto& v4l2Fmt : supportedFormats) {
+        if (width == v4l2Fmt.width && height == v4l2Fmt.height) {
+            return true;
+        }
+    }
+    ALOGI("%s: resolution %dx%d is not supported", __FUNCTION__, width, height);
+    return false;
+}
+
+Status ExternalCameraDeviceSession::importRequestLocked(const CaptureRequest& request,
+                                                        std::vector<buffer_handle_t*>& allBufPtrs,
+                                                        std::vector<int>& allFences) {
+    return importRequestLockedImpl(request, allBufPtrs, allFences);
+}
+
+Status ExternalCameraDeviceSession::importRequestLockedImpl(
+        const CaptureRequest& request, std::vector<buffer_handle_t*>& allBufPtrs,
+        std::vector<int>& allFences) {
+    size_t numOutputBufs = request.outputBuffers.size();
+    size_t numBufs = numOutputBufs;
+    // Validate all I/O buffers
+    std::vector<buffer_handle_t> allBufs;
+    std::vector<uint64_t> allBufIds;
+    allBufs.resize(numBufs);
+    allBufIds.resize(numBufs);
+    allBufPtrs.resize(numBufs);
+    allFences.resize(numBufs);
+    std::vector<int32_t> streamIds(numBufs);
+
+    for (size_t i = 0; i < numOutputBufs; i++) {
+        allBufs[i] = ::android::makeFromAidl(request.outputBuffers[i].buffer);
+        allBufIds[i] = request.outputBuffers[i].bufferId;
+        allBufPtrs[i] = &allBufs[i];
+        streamIds[i] = request.outputBuffers[i].streamId;
+    }
+
+    {
+        Mutex::Autolock _l(mCbsLock);
+        for (size_t i = 0; i < numBufs; i++) {
+            Status st = importBufferLocked(streamIds[i], allBufIds[i], allBufs[i], &allBufPtrs[i]);
+            if (st != Status::OK) {
+                // Detailed error logs printed in importBuffer
+                return st;
+            }
+        }
+    }
+
+    // All buffers are imported. Now validate output buffer acquire fences
+    for (size_t i = 0; i < numOutputBufs; i++) {
+        if (!sHandleImporter.importFence(
+                    ::android::makeFromAidl(request.outputBuffers[i].acquireFence), allFences[i])) {
+            ALOGE("%s: output buffer %zu acquire fence is invalid", __FUNCTION__, i);
+            cleanupInflightFences(allFences, i);
+            return Status::INTERNAL_ERROR;
+        }
+    }
+    return Status::OK;
+}
+
+Status ExternalCameraDeviceSession::importBuffer(int32_t streamId, uint64_t bufId,
+                                                 buffer_handle_t buf,
+                                                 /*out*/ buffer_handle_t** outBufPtr) {
+    Mutex::Autolock _l(mCbsLock);
+    return importBufferLocked(streamId, bufId, buf, outBufPtr);
+}
+
+Status ExternalCameraDeviceSession::importBufferLocked(int32_t streamId, uint64_t bufId,
+                                                       buffer_handle_t buf,
+                                                       buffer_handle_t** outBufPtr) {
+    return importBufferImpl(mCirculatingBuffers, sHandleImporter, streamId, bufId, buf, outBufPtr);
+}
+
+ScopedAStatus ExternalCameraDeviceSession::close() {
+    close(false);
+    return fromStatus(Status::OK);
+}
+
+void ExternalCameraDeviceSession::close(bool callerIsDtor) {
+    Mutex::Autolock _il(mInterfaceLock);
+    bool closed = isClosed();
+    if (!closed) {
+        if (callerIsDtor) {
+            closeOutputThreadImpl();
+        } else {
+            closeOutputThread();
+        }
+
+        Mutex::Autolock _l(mLock);
+        // free all buffers
+        {
+            Mutex::Autolock _cbsl(mCbsLock);
+            for (auto pair : mStreamMap) {
+                cleanupBuffersLocked(/*Stream ID*/ pair.first);
+            }
+        }
+        v4l2StreamOffLocked();
+        ALOGV("%s: closing V4L2 camera FD %d", __FUNCTION__, mV4l2Fd.get());
+        mV4l2Fd.reset();
+        mClosed = true;
+    }
+}
+
+bool ExternalCameraDeviceSession::isClosed() {
+    Mutex::Autolock _l(mLock);
+    return mClosed;
+}
+
+ScopedAStatus ExternalCameraDeviceSession::repeatingRequestEnd(
+        int32_t /*in_frameNumber*/, const std::vector<int32_t>& /*in_streamIds*/) {
+    // TODO: Figure this one out.
+    return fromStatus(Status::OK);
+}
+
+int ExternalCameraDeviceSession::v4l2StreamOffLocked() {
+    if (!mV4l2Streaming) {
+        return OK;
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(mV4l2BufferLock);
+        if (mNumDequeuedV4l2Buffers != 0) {
+            ALOGE("%s: there are %zu inflight V4L buffers", __FUNCTION__, mNumDequeuedV4l2Buffers);
+            return -1;
+        }
+    }
+    mV4L2BufferCount = 0;
+
+    // VIDIOC_STREAMOFF
+    v4l2_buf_type capture_type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_STREAMOFF, &capture_type)) < 0) {
+        ALOGE("%s: STREAMOFF failed: %s", __FUNCTION__, strerror(errno));
+        return -errno;
+    }
+
+    // VIDIOC_REQBUFS: clear buffers
+    v4l2_requestbuffers req_buffers{};
+    req_buffers.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+    req_buffers.memory = V4L2_MEMORY_MMAP;
+    req_buffers.count = 0;
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_REQBUFS, &req_buffers)) < 0) {
+        ALOGE("%s: REQBUFS failed: %s", __FUNCTION__, strerror(errno));
+        return -errno;
+    }
+
+    mV4l2Streaming = false;
+    return OK;
+}
+
+int ExternalCameraDeviceSession::setV4l2FpsLocked(double fps) {
+    // VIDIOC_G_PARM/VIDIOC_S_PARM: set fps
+    v4l2_streamparm streamparm = {.type = V4L2_BUF_TYPE_VIDEO_CAPTURE};
+    // The following line checks that the driver knows about framerate get/set.
+    int ret = TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_G_PARM, &streamparm));
+    if (ret != 0) {
+        if (errno == -EINVAL) {
+            ALOGW("%s: device does not support VIDIOC_G_PARM", __FUNCTION__);
+        }
+        return -errno;
+    }
+    // Now check if the device is able to accept a capture framerate set.
+    if (!(streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME)) {
+        ALOGW("%s: device does not support V4L2_CAP_TIMEPERFRAME", __FUNCTION__);
+        return -EINVAL;
+    }
+
+    // fps is float, approximate by a fraction.
+    const int kFrameRatePrecision = 10000;
+    streamparm.parm.capture.timeperframe.numerator = kFrameRatePrecision;
+    streamparm.parm.capture.timeperframe.denominator = (fps * kFrameRatePrecision);
+
+    if (TEMP_FAILURE_RETRY(ioctl(mV4l2Fd.get(), VIDIOC_S_PARM, &streamparm)) < 0) {
+        ALOGE("%s: failed to set framerate to %f: %s", __FUNCTION__, fps, strerror(errno));
+        return -1;
+    }
+
+    double retFps = streamparm.parm.capture.timeperframe.denominator /
+                    static_cast<double>(streamparm.parm.capture.timeperframe.numerator);
+    if (std::fabs(fps - retFps) > 1.0) {
+        ALOGE("%s: expect fps %f, got %f instead", __FUNCTION__, fps, retFps);
+        return -1;
+    }
+    mV4l2StreamingFps = fps;
+    return 0;
+}
+
+void ExternalCameraDeviceSession::cleanupInflightFences(std::vector<int>& allFences,
+                                                        size_t numFences) {
+    for (size_t j = 0; j < numFences; j++) {
+        sHandleImporter.closeFence(allFences[j]);
+    }
+}
+
+void ExternalCameraDeviceSession::cleanupBuffersLocked(int id) {
+    for (auto& pair : mCirculatingBuffers.at(id)) {
+        sHandleImporter.freeBuffer(pair.second);
+    }
+    mCirculatingBuffers[id].clear();
+    mCirculatingBuffers.erase(id);
+}
+
+void ExternalCameraDeviceSession::notifyShutter(int32_t frameNumber, nsecs_t shutterTs) {
+    NotifyMsg msg;
+    msg.set<NotifyMsg::Tag::shutter>(ShutterMsg{
+            .frameNumber = frameNumber,
+            .timestamp = shutterTs,
+    });
+    mCallback->notify({msg});
+}
+void ExternalCameraDeviceSession::notifyError(int32_t frameNumber, int32_t streamId, ErrorCode ec) {
+    NotifyMsg msg;
+    msg.set<NotifyMsg::Tag::error>(ErrorMsg{
+            .frameNumber = frameNumber,
+            .errorStreamId = streamId,
+            .errorCode = ec,
+    });
+    mCallback->notify({msg});
+}
+
+void ExternalCameraDeviceSession::invokeProcessCaptureResultCallback(
+        std::vector<CaptureResult>& results, bool tryWriteFmq) {
+    if (mProcessCaptureResultLock.tryLock() != OK) {
+        const nsecs_t NS_TO_SECOND = 1000000000;
+        ALOGV("%s: previous call is not finished! waiting 1s...", __FUNCTION__);
+        if (mProcessCaptureResultLock.timedLock(/* 1s */ NS_TO_SECOND) != OK) {
+            ALOGE("%s: cannot acquire lock in 1s, cannot proceed", __FUNCTION__);
+            return;
+        }
+    }
+    if (tryWriteFmq && mResultMetadataQueue->availableToWrite() > 0) {
+        for (CaptureResult& result : results) {
+            CameraMetadata& md = result.result;
+            if (!md.metadata.empty()) {
+                if (mResultMetadataQueue->write(reinterpret_cast<int8_t*>(md.metadata.data()),
+                                                md.metadata.size())) {
+                    result.fmqResultSize = md.metadata.size();
+                    md.metadata.resize(0);
+                } else {
+                    ALOGW("%s: couldn't utilize fmq, fall back to hwbinder", __FUNCTION__);
+                    result.fmqResultSize = 0;
+                }
+            } else {
+                result.fmqResultSize = 0;
+            }
+        }
+    }
+    auto status = mCallback->processCaptureResult(results);
+    if (!status.isOk()) {
+        ALOGE("%s: processCaptureResult ERROR : %d:%d", __FUNCTION__, status.getExceptionCode(),
+              status.getServiceSpecificError());
+    }
+
+    mProcessCaptureResultLock.unlock();
+}
+
+int ExternalCameraDeviceSession::waitForV4L2BufferReturnLocked(std::unique_lock<std::mutex>& lk) {
+    ATRACE_CALL();
+    auto timeout = std::chrono::seconds(kBufferWaitTimeoutSec);
+    mLock.unlock();
+    auto st = mV4L2BufferReturned.wait_for(lk, timeout);
+    // Here we introduce an order where mV4l2BufferLock is acquired before mLock, while
+    // the normal lock acquisition order is reversed. This is fine because in most of
+    // cases we are protected by mInterfaceLock. The only thread that can cause deadlock
+    // is the OutputThread, where we do need to make sure we don't acquire mLock then
+    // mV4l2BufferLock
+    mLock.lock();
+    if (st == std::cv_status::timeout) {
+        ALOGE("%s: wait for V4L2 buffer return timeout!", __FUNCTION__);
+        return -1;
+    }
+    return 0;
+}
+
+bool ExternalCameraDeviceSession::supportOfflineLocked(int32_t streamId) {
+    const Stream& stream = mStreamMap[streamId];
+    if (stream.format == PixelFormat::BLOB &&
+        static_cast<int32_t>(stream.dataSpace) == static_cast<int32_t>(Dataspace::JFIF)) {
+        return true;
+    }
+    // TODO: support YUV output stream?
+    return false;
+}
+
+bool ExternalCameraDeviceSession::canDropRequest(const std::vector<int32_t>& offlineStreams,
+                                                 std::shared_ptr<HalRequest> halReq) {
+    for (const auto& buffer : halReq->buffers) {
+        for (auto offlineStreamId : offlineStreams) {
+            if (buffer.streamId == offlineStreamId) {
+                return false;
+            }
+        }
+    }
+    // Only drop a request completely if it has no offline output
+    return true;
+}
+
+void ExternalCameraDeviceSession::fillOfflineSessionInfo(
+        const std::vector<int32_t>& offlineStreams,
+        std::deque<std::shared_ptr<HalRequest>>& offlineReqs,
+        const std::map<int, CirculatingBuffers>& circulatingBuffers,
+        CameraOfflineSessionInfo* info) {
+    if (info == nullptr) {
+        ALOGE("%s: output info must not be null!", __FUNCTION__);
+        return;
+    }
+
+    info->offlineStreams.resize(offlineStreams.size());
+    info->offlineRequests.resize(offlineReqs.size());
+
+    // Fill in offline reqs and count outstanding buffers
+    for (size_t i = 0; i < offlineReqs.size(); i++) {
+        info->offlineRequests[i].frameNumber = offlineReqs[i]->frameNumber;
+        info->offlineRequests[i].pendingStreams.resize(offlineReqs[i]->buffers.size());
+        for (size_t bIdx = 0; bIdx < offlineReqs[i]->buffers.size(); bIdx++) {
+            int32_t streamId = offlineReqs[i]->buffers[bIdx].streamId;
+            info->offlineRequests[i].pendingStreams[bIdx] = streamId;
+        }
+    }
+
+    for (size_t i = 0; i < offlineStreams.size(); i++) {
+        int32_t streamId = offlineStreams[i];
+        info->offlineStreams[i].id = streamId;
+        // outstanding buffers are 0 since we are doing hal buffer management and
+        // offline session will ask for those buffers later
+        info->offlineStreams[i].numOutstandingBuffers = 0;
+        const CirculatingBuffers& bufIdMap = circulatingBuffers.at(streamId);
+        info->offlineStreams[i].circulatingBufferIds.resize(bufIdMap.size());
+        size_t bIdx = 0;
+        for (const auto& pair : bufIdMap) {
+            // Fill in bufferId
+            info->offlineStreams[i].circulatingBufferIds[bIdx++] = pair.first;
+        }
+    }
+}
+
+Status ExternalCameraDeviceSession::isStreamCombinationSupported(
+        const StreamConfiguration& config, const std::vector<SupportedV4L2Format>& supportedFormats,
+        const ExternalCameraConfig& devCfg) {
+    if (config.operationMode != StreamConfigurationMode::NORMAL_MODE) {
+        ALOGE("%s: unsupported operation mode: %d", __FUNCTION__, config.operationMode);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    if (config.streams.size() == 0) {
+        ALOGE("%s: cannot configure zero stream", __FUNCTION__);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    int numProcessedStream = 0;
+    int numStallStream = 0;
+    for (const auto& stream : config.streams) {
+        // Check if the format/width/height combo is supported
+        if (!isSupported(stream, supportedFormats, devCfg)) {
+            return Status::ILLEGAL_ARGUMENT;
+        }
+        if (stream.format == PixelFormat::BLOB) {
+            numStallStream++;
+        } else {
+            numProcessedStream++;
+        }
+    }
+
+    if (numProcessedStream > kMaxProcessedStream) {
+        ALOGE("%s: too many processed streams (expect <= %d, got %d)", __FUNCTION__,
+              kMaxProcessedStream, numProcessedStream);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    if (numStallStream > kMaxStallStream) {
+        ALOGE("%s: too many stall streams (expect <= %d, got %d)", __FUNCTION__, kMaxStallStream,
+              numStallStream);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    return Status::OK;
+}
+void ExternalCameraDeviceSession::updateBufferCaches(
+        const std::vector<BufferCache>& cachesToRemove) {
+    Mutex::Autolock _l(mCbsLock);
+    for (auto& cache : cachesToRemove) {
+        auto cbsIt = mCirculatingBuffers.find(cache.streamId);
+        if (cbsIt == mCirculatingBuffers.end()) {
+            // The stream could have been removed
+            continue;
+        }
+        CirculatingBuffers& cbs = cbsIt->second;
+        auto it = cbs.find(cache.bufferId);
+        if (it != cbs.end()) {
+            sHandleImporter.freeBuffer(it->second);
+            cbs.erase(it);
+        } else {
+            ALOGE("%s: stream %d buffer %" PRIu64 " is not cached", __FUNCTION__, cache.streamId,
+                  cache.bufferId);
+        }
+    }
+}
+
+Status ExternalCameraDeviceSession::processCaptureRequestError(
+        const std::shared_ptr<HalRequest>& req, std::vector<NotifyMsg>* outMsgs,
+        std::vector<CaptureResult>* outResults) {
+    ATRACE_CALL();
+    // Return V4L2 buffer to V4L2 buffer queue
+    std::shared_ptr<V4L2Frame> v4l2Frame = std::static_pointer_cast<V4L2Frame>(req->frameIn);
+    enqueueV4l2Frame(v4l2Frame);
+
+    if (outMsgs == nullptr) {
+        notifyShutter(req->frameNumber, req->shutterTs);
+        notifyError(/*frameNum*/ req->frameNumber, /*stream*/ -1, ErrorCode::ERROR_REQUEST);
+    } else {
+        NotifyMsg shutter;
+        shutter.set<NotifyMsg::Tag::shutter>(
+                ShutterMsg{.frameNumber = req->frameNumber, .timestamp = req->shutterTs});
+
+        NotifyMsg error;
+        error.set<NotifyMsg::Tag::error>(ErrorMsg{.frameNumber = req->frameNumber,
+                                                  .errorStreamId = -1,
+                                                  .errorCode = ErrorCode::ERROR_REQUEST});
+        outMsgs->push_back(shutter);
+        outMsgs->push_back(error);
+    }
+
+    // Fill output buffers
+    CaptureResult result;
+    result.frameNumber = req->frameNumber;
+    result.partialResult = 1;
+    result.inputBuffer.streamId = -1;
+    result.outputBuffers.resize(req->buffers.size());
+    for (size_t i = 0; i < req->buffers.size(); i++) {
+        result.outputBuffers[i].streamId = req->buffers[i].streamId;
+        result.outputBuffers[i].bufferId = req->buffers[i].bufferId;
+        result.outputBuffers[i].status = BufferStatus::ERROR;
+        if (req->buffers[i].acquireFence >= 0) {
+            native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+            handle->data[0] = req->buffers[i].acquireFence;
+            result.outputBuffers[i].releaseFence = ::android::makeToAidl(handle);
+        }
+    }
+
+    // update inflight records
+    {
+        std::lock_guard<std::mutex> lk(mInflightFramesLock);
+        mInflightFrames.erase(req->frameNumber);
+    }
+
+    if (outResults == nullptr) {
+        // Callback into framework
+        std::vector<CaptureResult> results(1);
+        results[0] = std::move(result);
+        invokeProcessCaptureResultCallback(results, /* tryWriteFmq */ true);
+        freeReleaseFences(results);
+    } else {
+        outResults->push_back(std::move(result));
+    }
+    return Status::OK;
+}
+
+Status ExternalCameraDeviceSession::processCaptureResult(std::shared_ptr<HalRequest>& req) {
+    ATRACE_CALL();
+    // Return V4L2 buffer to V4L2 buffer queue
+    std::shared_ptr<V4L2Frame> v4l2Frame = std::static_pointer_cast<V4L2Frame>(req->frameIn);
+    enqueueV4l2Frame(v4l2Frame);
+
+    // NotifyShutter
+    notifyShutter(req->frameNumber, req->shutterTs);
+
+    // Fill output buffers;
+    std::vector<CaptureResult> results(1);
+    CaptureResult& result = results[0];
+    result.frameNumber = req->frameNumber;
+    result.partialResult = 1;
+    result.inputBuffer.streamId = -1;
+    result.outputBuffers.resize(req->buffers.size());
+    for (size_t i = 0; i < req->buffers.size(); i++) {
+        result.outputBuffers[i].streamId = req->buffers[i].streamId;
+        result.outputBuffers[i].bufferId = req->buffers[i].bufferId;
+        if (req->buffers[i].fenceTimeout) {
+            result.outputBuffers[i].status = BufferStatus::ERROR;
+            if (req->buffers[i].acquireFence >= 0) {
+                native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+                handle->data[0] = req->buffers[i].acquireFence;
+                result.outputBuffers[i].releaseFence = ::android::makeToAidl(handle);
+            }
+            notifyError(req->frameNumber, req->buffers[i].streamId, ErrorCode::ERROR_BUFFER);
+        } else {
+            result.outputBuffers[i].status = BufferStatus::OK;
+            // TODO: refactor
+            if (req->buffers[i].acquireFence >= 0) {
+                native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+                handle->data[0] = req->buffers[i].acquireFence;
+                result.outputBuffers[i].releaseFence = ::android::makeToAidl(handle);
+            }
+        }
+    }
+
+    // Fill capture result metadata
+    fillCaptureResult(req->setting, req->shutterTs);
+    const camera_metadata_t* rawResult = req->setting.getAndLock();
+    convertToAidl(rawResult, &result.result);
+    req->setting.unlock(rawResult);
+
+    // update inflight records
+    {
+        std::lock_guard<std::mutex> lk(mInflightFramesLock);
+        mInflightFrames.erase(req->frameNumber);
+    }
+
+    // Callback into framework
+    invokeProcessCaptureResultCallback(results, /* tryWriteFmq */ true);
+    freeReleaseFences(results);
+    return Status::OK;
+}
+
+ssize_t ExternalCameraDeviceSession::getJpegBufferSize(int32_t width, int32_t height) const {
+    // Constant from camera3.h
+    const ssize_t kMinJpegBufferSize = 256 * 1024 + sizeof(CameraBlob);
+    // Get max jpeg size (area-wise).
+    if (mMaxJpegResolution.width == 0) {
+        ALOGE("%s: No supported JPEG stream", __FUNCTION__);
+        return BAD_VALUE;
+    }
+
+    // Get max jpeg buffer size
+    ssize_t maxJpegBufferSize = 0;
+    camera_metadata_ro_entry jpegBufMaxSize = mCameraCharacteristics.find(ANDROID_JPEG_MAX_SIZE);
+    if (jpegBufMaxSize.count == 0) {
+        ALOGE("%s: Can't find maximum JPEG size in static metadata!", __FUNCTION__);
+        return BAD_VALUE;
+    }
+    maxJpegBufferSize = jpegBufMaxSize.data.i32[0];
+
+    if (maxJpegBufferSize <= kMinJpegBufferSize) {
+        ALOGE("%s: ANDROID_JPEG_MAX_SIZE (%zd) <= kMinJpegBufferSize (%zd)", __FUNCTION__,
+              maxJpegBufferSize, kMinJpegBufferSize);
+        return BAD_VALUE;
+    }
+
+    // Calculate final jpeg buffer size for the given resolution.
+    float scaleFactor =
+            ((float)(width * height)) / (mMaxJpegResolution.width * mMaxJpegResolution.height);
+    ssize_t jpegBufferSize =
+            scaleFactor * (maxJpegBufferSize - kMinJpegBufferSize) + kMinJpegBufferSize;
+    if (jpegBufferSize > maxJpegBufferSize) {
+        jpegBufferSize = maxJpegBufferSize;
+    }
+
+    return jpegBufferSize;
+}
+binder_status_t ExternalCameraDeviceSession::dump(int fd, const char** /*args*/,
+                                                  uint32_t /*numArgs*/) {
+    bool intfLocked = tryLock(mInterfaceLock);
+    if (!intfLocked) {
+        dprintf(fd, "!! ExternalCameraDeviceSession interface may be deadlocked !!\n");
+    }
+
+    if (isClosed()) {
+        dprintf(fd, "External camera %s is closed\n", mCameraId.c_str());
+        return STATUS_OK;
+    }
+
+    bool streaming = false;
+    size_t v4L2BufferCount = 0;
+    SupportedV4L2Format streamingFmt;
+    {
+        bool sessionLocked = tryLock(mLock);
+        if (!sessionLocked) {
+            dprintf(fd, "!! ExternalCameraDeviceSession mLock may be deadlocked !!\n");
+        }
+        streaming = mV4l2Streaming;
+        streamingFmt = mV4l2StreamingFmt;
+        v4L2BufferCount = mV4L2BufferCount;
+
+        if (sessionLocked) {
+            mLock.unlock();
+        }
+    }
+
+    std::unordered_set<uint32_t> inflightFrames;
+    {
+        bool iffLocked = tryLock(mInflightFramesLock);
+        if (!iffLocked) {
+            dprintf(fd,
+                    "!! ExternalCameraDeviceSession mInflightFramesLock may be deadlocked !!\n");
+        }
+        inflightFrames = mInflightFrames;
+        if (iffLocked) {
+            mInflightFramesLock.unlock();
+        }
+    }
+
+    dprintf(fd, "External camera %s V4L2 FD %d, cropping type %s, %s\n", mCameraId.c_str(),
+            mV4l2Fd.get(), (mCroppingType == VERTICAL) ? "vertical" : "horizontal",
+            streaming ? "streaming" : "not streaming");
+
+    if (streaming) {
+        // TODO: dump fps later
+        dprintf(fd, "Current V4L2 format %c%c%c%c %dx%d @ %ffps\n", streamingFmt.fourcc & 0xFF,
+                (streamingFmt.fourcc >> 8) & 0xFF, (streamingFmt.fourcc >> 16) & 0xFF,
+                (streamingFmt.fourcc >> 24) & 0xFF, streamingFmt.width, streamingFmt.height,
+                mV4l2StreamingFps);
+
+        size_t numDequeuedV4l2Buffers = 0;
+        {
+            std::lock_guard<std::mutex> lk(mV4l2BufferLock);
+            numDequeuedV4l2Buffers = mNumDequeuedV4l2Buffers;
+        }
+        dprintf(fd, "V4L2 buffer queue size %zu, dequeued %zu\n", v4L2BufferCount,
+                numDequeuedV4l2Buffers);
+    }
+
+    dprintf(fd, "In-flight frames (not sorted):");
+    for (const auto& frameNumber : inflightFrames) {
+        dprintf(fd, "%d, ", frameNumber);
+    }
+    dprintf(fd, "\n");
+    mOutputThread->dump(fd);
+    dprintf(fd, "\n");
+
+    if (intfLocked) {
+        mInterfaceLock.unlock();
+    }
+
+    return STATUS_OK;
+}
+
+// Start ExternalCameraDeviceSession::BufferRequestThread functions
+ExternalCameraDeviceSession::BufferRequestThread::BufferRequestThread(
+        std::weak_ptr<OutputThreadInterface> parent,
+        std::shared_ptr<ICameraDeviceCallback> callbacks)
+    : mParent(parent), mCallbacks(callbacks) {}
+
+int ExternalCameraDeviceSession::BufferRequestThread::requestBufferStart(
+        const std::vector<HalStreamBuffer>& bufReqs) {
+    if (bufReqs.empty()) {
+        ALOGE("%s: bufReqs is empty!", __FUNCTION__);
+        return -1;
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(mLock);
+        if (mRequestingBuffer) {
+            ALOGE("%s: BufferRequestThread does not support more than one concurrent request!",
+                  __FUNCTION__);
+            return -1;
+        }
+
+        mBufferReqs = bufReqs;
+        mRequestingBuffer = true;
+    }
+    mRequestCond.notify_one();
+    return 0;
+}
+
+int ExternalCameraDeviceSession::BufferRequestThread::waitForBufferRequestDone(
+        std::vector<HalStreamBuffer>* outBufReqs) {
+    std::unique_lock<std::mutex> lk(mLock);
+    if (!mRequestingBuffer) {
+        ALOGE("%s: no pending buffer request!", __FUNCTION__);
+        return -1;
+    }
+
+    if (mPendingReturnBufferReqs.empty()) {
+        std::chrono::milliseconds timeout = std::chrono::milliseconds(kReqProcTimeoutMs);
+        auto st = mRequestDoneCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            ALOGE("%s: wait for buffer request finish timeout!", __FUNCTION__);
+            return -1;
+        }
+    }
+    mRequestingBuffer = false;
+    *outBufReqs = std::move(mPendingReturnBufferReqs);
+    mPendingReturnBufferReqs.clear();
+    return 0;
+}
+
+void ExternalCameraDeviceSession::BufferRequestThread::waitForNextRequest() {
+    ATRACE_CALL();
+    std::unique_lock<std::mutex> lk(mLock);
+    int waitTimes = 0;
+    while (mBufferReqs.empty()) {
+        if (exitPending()) {
+            return;
+        }
+        auto timeout = std::chrono::milliseconds(kReqWaitTimeoutMs);
+        auto st = mRequestCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            waitTimes++;
+            if (waitTimes == kReqWaitTimesWarn) {
+                // BufferRequestThread just wait forever for new buffer request
+                // But it will print some periodic warning indicating it's waiting
+                ALOGV("%s: still waiting for new buffer request", __FUNCTION__);
+                waitTimes = 0;
+            }
+        }
+    }
+
+    // Fill in BufferRequest
+    mHalBufferReqs.resize(mBufferReqs.size());
+    for (size_t i = 0; i < mHalBufferReqs.size(); i++) {
+        mHalBufferReqs[i].streamId = mBufferReqs[i].streamId;
+        mHalBufferReqs[i].numBuffersRequested = 1;
+    }
+}
+
+bool ExternalCameraDeviceSession::BufferRequestThread::threadLoop() {
+    waitForNextRequest();
+    if (exitPending()) {
+        return false;
+    }
+
+    ATRACE_BEGIN("AIDL requestStreamBuffers");
+    BufferRequestStatus status;
+    std::vector<StreamBufferRet> bufRets;
+    ScopedAStatus ret = mCallbacks->requestStreamBuffers(mHalBufferReqs, &bufRets, &status);
+    if (!ret.isOk()) {
+        ALOGE("%s: Transaction error: %d:%d", __FUNCTION__, ret.getExceptionCode(),
+              ret.getServiceSpecificError());
+        return false;
+    }
+
+    std::unique_lock<std::mutex> lk(mLock);
+    if (status == BufferRequestStatus::OK || status == BufferRequestStatus::FAILED_PARTIAL) {
+        if (bufRets.size() != mHalBufferReqs.size()) {
+            ALOGE("%s: expect %zu buffer requests returned, only got %zu", __FUNCTION__,
+                  mHalBufferReqs.size(), bufRets.size());
+            return false;
+        }
+
+        auto parent = mParent.lock();
+        if (parent == nullptr) {
+            ALOGE("%s: session has been disconnected!", __FUNCTION__);
+            return false;
+        }
+
+        std::vector<int> importedFences;
+        importedFences.resize(bufRets.size());
+        for (size_t i = 0; i < bufRets.size(); i++) {
+            int streamId = bufRets[i].streamId;
+            switch (bufRets[i].val.getTag()) {
+                case StreamBuffersVal::Tag::error:
+                    continue;
+                case StreamBuffersVal::Tag::buffers: {
+                    const std::vector<StreamBuffer>& hBufs =
+                            bufRets[i].val.get<StreamBuffersVal::Tag::buffers>();
+                    if (hBufs.size() != 1) {
+                        ALOGE("%s: expect 1 buffer returned, got %zu!", __FUNCTION__, hBufs.size());
+                        return false;
+                    }
+                    const StreamBuffer& hBuf = hBufs[0];
+
+                    mBufferReqs[i].bufferId = hBuf.bufferId;
+                    // TODO: create a batch import API so we don't need to lock/unlock mCbsLock
+                    // repeatedly?
+                    lk.unlock();
+                    Status s =
+                            parent->importBuffer(streamId, hBuf.bufferId, makeFromAidl(hBuf.buffer),
+                                                 /*out*/ &mBufferReqs[i].bufPtr);
+                    lk.lock();
+
+                    if (s != Status::OK) {
+                        ALOGE("%s: stream %d import buffer failed!", __FUNCTION__, streamId);
+                        cleanupInflightFences(importedFences, i - 1);
+                        return false;
+                    }
+                    if (!sHandleImporter.importFence(makeFromAidl(hBuf.acquireFence),
+                                                     mBufferReqs[i].acquireFence)) {
+                        ALOGE("%s: stream %d import fence failed!", __FUNCTION__, streamId);
+                        cleanupInflightFences(importedFences, i - 1);
+                        return false;
+                    }
+                    importedFences[i] = mBufferReqs[i].acquireFence;
+                } break;
+                default:
+                    ALOGE("%s: Unknown StreamBuffersVal!", __FUNCTION__);
+                    return false;
+            }
+        }
+    } else {
+        ALOGE("%s: requestStreamBuffers call failed!", __FUNCTION__);
+    }
+
+    mPendingReturnBufferReqs = std::move(mBufferReqs);
+    mBufferReqs.clear();
+
+    lk.unlock();
+    mRequestDoneCond.notify_one();
+    return true;
+}
+
+// End ExternalCameraDeviceSession::BufferRequestThread functions
+
+// Start ExternalCameraDeviceSession::OutputThread functions
+
+ExternalCameraDeviceSession::OutputThread::OutputThread(
+        std::weak_ptr<OutputThreadInterface> parent, CroppingType ct,
+        const common::V1_0::helper::CameraMetadata& chars,
+        std::shared_ptr<BufferRequestThread> bufReqThread)
+    : mParent(parent),
+      mCroppingType(ct),
+      mCameraCharacteristics(chars),
+      mBufferRequestThread(bufReqThread) {}
+
+ExternalCameraDeviceSession::OutputThread::~OutputThread() {}
+
+Status ExternalCameraDeviceSession::OutputThread::allocateIntermediateBuffers(
+        const Size& v4lSize, const Size& thumbSize, const std::vector<Stream>& streams,
+        uint32_t blobBufferSize) {
+    std::lock_guard<std::mutex> lk(mBufferLock);
+    if (!mScaledYu12Frames.empty()) {
+        ALOGE("%s: intermediate buffer pool has %zu inflight buffers! (expect 0)", __FUNCTION__,
+              mScaledYu12Frames.size());
+        return Status::INTERNAL_ERROR;
+    }
+
+    // Allocating intermediate YU12 frame
+    if (mYu12Frame == nullptr || mYu12Frame->mWidth != v4lSize.width ||
+        mYu12Frame->mHeight != v4lSize.height) {
+        mYu12Frame.reset();
+        mYu12Frame = std::make_shared<AllocatedFrame>(v4lSize.width, v4lSize.height);
+        int ret = mYu12Frame->allocate(&mYu12FrameLayout);
+        if (ret != 0) {
+            ALOGE("%s: allocating YU12 frame failed!", __FUNCTION__);
+            return Status::INTERNAL_ERROR;
+        }
+    }
+
+    // Allocating intermediate YU12 thumbnail frame
+    if (mYu12ThumbFrame == nullptr || mYu12ThumbFrame->mWidth != thumbSize.width ||
+        mYu12ThumbFrame->mHeight != thumbSize.height) {
+        mYu12ThumbFrame.reset();
+        mYu12ThumbFrame = std::make_shared<AllocatedFrame>(thumbSize.width, thumbSize.height);
+        int ret = mYu12ThumbFrame->allocate(&mYu12ThumbFrameLayout);
+        if (ret != 0) {
+            ALOGE("%s: allocating YU12 thumb frame failed!", __FUNCTION__);
+            return Status::INTERNAL_ERROR;
+        }
+    }
+
+    // Allocating scaled buffers
+    for (const auto& stream : streams) {
+        Size sz = {stream.width, stream.height};
+        if (sz == v4lSize) {
+            continue;  // Don't need an intermediate buffer same size as v4lBuffer
+        }
+        if (mIntermediateBuffers.count(sz) == 0) {
+            // Create new intermediate buffer
+            std::shared_ptr<AllocatedFrame> buf =
+                    std::make_shared<AllocatedFrame>(stream.width, stream.height);
+            int ret = buf->allocate();
+            if (ret != 0) {
+                ALOGE("%s: allocating intermediate YU12 frame %dx%d failed!", __FUNCTION__,
+                      stream.width, stream.height);
+                return Status::INTERNAL_ERROR;
+            }
+            mIntermediateBuffers[sz] = buf;
+        }
+    }
+
+    // Remove unconfigured buffers
+    auto it = mIntermediateBuffers.begin();
+    while (it != mIntermediateBuffers.end()) {
+        bool configured = false;
+        auto sz = it->first;
+        for (const auto& stream : streams) {
+            if (stream.width == sz.width && stream.height == sz.height) {
+                configured = true;
+                break;
+            }
+        }
+        if (configured) {
+            it++;
+        } else {
+            it = mIntermediateBuffers.erase(it);
+        }
+    }
+
+    // Allocate mute test pattern frame
+    mMuteTestPatternFrame.resize(mYu12Frame->mWidth * mYu12Frame->mHeight * 3);
+
+    mBlobBufferSize = blobBufferSize;
+    return Status::OK;
+}
+
+Status ExternalCameraDeviceSession::OutputThread::submitRequest(
+        const std::shared_ptr<HalRequest>& req) {
+    std::unique_lock<std::mutex> lk(mRequestListLock);
+    mRequestList.push_back(req);
+    lk.unlock();
+    mRequestCond.notify_one();
+    return Status::OK;
+}
+
+void ExternalCameraDeviceSession::OutputThread::flush() {
+    ATRACE_CALL();
+    auto parent = mParent.lock();
+    if (parent == nullptr) {
+        ALOGE("%s: session has been disconnected!", __FUNCTION__);
+        return;
+    }
+
+    std::unique_lock<std::mutex> lk(mRequestListLock);
+    std::list<std::shared_ptr<HalRequest>> reqs = std::move(mRequestList);
+    mRequestList.clear();
+    if (mProcessingRequest) {
+        auto timeout = std::chrono::seconds(kFlushWaitTimeoutSec);
+        auto st = mRequestDoneCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            ALOGE("%s: wait for inflight request finish timeout!", __FUNCTION__);
+        }
+    }
+
+    ALOGV("%s: flushing inflight requests", __FUNCTION__);
+    lk.unlock();
+    for (const auto& req : reqs) {
+        parent->processCaptureRequestError(req);
+    }
+}
+
+void ExternalCameraDeviceSession::OutputThread::dump(int fd) {
+    std::lock_guard<std::mutex> lk(mRequestListLock);
+    if (mProcessingRequest) {
+        dprintf(fd, "OutputThread processing frame %d\n", mProcessingFrameNumber);
+    } else {
+        dprintf(fd, "OutputThread not processing any frames\n");
+    }
+    dprintf(fd, "OutputThread request list contains frame: ");
+    for (const auto& req : mRequestList) {
+        dprintf(fd, "%d, ", req->frameNumber);
+    }
+    dprintf(fd, "\n");
+}
+
+void ExternalCameraDeviceSession::OutputThread::setExifMakeModel(const std::string& make,
+                                                                 const std::string& model) {
+    mExifMake = make;
+    mExifModel = model;
+}
+
+std::list<std::shared_ptr<HalRequest>>
+ExternalCameraDeviceSession::OutputThread::switchToOffline() {
+    ATRACE_CALL();
+    auto parent = mParent.lock();
+    if (parent == nullptr) {
+        ALOGE("%s: session has been disconnected!", __FUNCTION__);
+        return {};
+    }
+
+    std::unique_lock<std::mutex> lk(mRequestListLock);
+    std::list<std::shared_ptr<HalRequest>> reqs = std::move(mRequestList);
+    mRequestList.clear();
+    if (mProcessingRequest) {
+        auto timeout = std::chrono::seconds(kFlushWaitTimeoutSec);
+        auto st = mRequestDoneCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            ALOGE("%s: wait for inflight request finish timeout!", __FUNCTION__);
+        }
+    }
+    lk.unlock();
+    clearIntermediateBuffers();
+    ALOGV("%s: returning %zu request for offline processing", __FUNCTION__, reqs.size());
+    return reqs;
+}
+
+int ExternalCameraDeviceSession::OutputThread::requestBufferStart(
+        const std::vector<HalStreamBuffer>& bufs) {
+    if (mBufferRequestThread == nullptr) {
+        return 0;
+    }
+    return mBufferRequestThread->requestBufferStart(bufs);
+}
+
+int ExternalCameraDeviceSession::OutputThread::waitForBufferRequestDone(
+        std::vector<HalStreamBuffer>* outBufs) {
+    if (mBufferRequestThread == nullptr) {
+        return 0;
+    }
+    return mBufferRequestThread->waitForBufferRequestDone(outBufs);
+}
+
+void ExternalCameraDeviceSession::OutputThread::waitForNextRequest(
+        std::shared_ptr<HalRequest>* out) {
+    ATRACE_CALL();
+    if (out == nullptr) {
+        ALOGE("%s: out is null", __FUNCTION__);
+        return;
+    }
+
+    std::unique_lock<std::mutex> lk(mRequestListLock);
+    int waitTimes = 0;
+    while (mRequestList.empty()) {
+        if (exitPending()) {
+            return;
+        }
+        auto timeout = std::chrono::milliseconds(kReqWaitTimeoutMs);
+        auto st = mRequestCond.wait_for(lk, timeout);
+        if (st == std::cv_status::timeout) {
+            waitTimes++;
+            if (waitTimes == kReqWaitTimesMax) {
+                // no new request, return
+                return;
+            }
+        }
+    }
+    *out = mRequestList.front();
+    mRequestList.pop_front();
+    mProcessingRequest = true;
+    mProcessingFrameNumber = (*out)->frameNumber;
+}
+
+void ExternalCameraDeviceSession::OutputThread::signalRequestDone() {
+    std::unique_lock<std::mutex> lk(mRequestListLock);
+    mProcessingRequest = false;
+    mProcessingFrameNumber = 0;
+    lk.unlock();
+    mRequestDoneCond.notify_one();
+}
+
+int ExternalCameraDeviceSession::OutputThread::cropAndScaleLocked(
+        std::shared_ptr<AllocatedFrame>& in, const Size& outSz, YCbCrLayout* out) {
+    Size inSz = {in->mWidth, in->mHeight};
+
+    int ret;
+    if (inSz == outSz) {
+        ret = in->getLayout(out);
+        if (ret != 0) {
+            ALOGE("%s: failed to get input image layout", __FUNCTION__);
+            return ret;
+        }
+        return ret;
+    }
+
+    // Cropping to output aspect ratio
+    IMapper::Rect inputCrop;
+    ret = getCropRect(mCroppingType, inSz, outSz, &inputCrop);
+    if (ret != 0) {
+        ALOGE("%s: failed to compute crop rect for output size %dx%d", __FUNCTION__, outSz.width,
+              outSz.height);
+        return ret;
+    }
+
+    YCbCrLayout croppedLayout;
+    ret = in->getCroppedLayout(inputCrop, &croppedLayout);
+    if (ret != 0) {
+        ALOGE("%s: failed to crop input image %dx%d to output size %dx%d", __FUNCTION__, inSz.width,
+              inSz.height, outSz.width, outSz.height);
+        return ret;
+    }
+
+    if ((mCroppingType == VERTICAL && inSz.width == outSz.width) ||
+        (mCroppingType == HORIZONTAL && inSz.height == outSz.height)) {
+        // No scale is needed
+        *out = croppedLayout;
+        return 0;
+    }
+
+    auto it = mScaledYu12Frames.find(outSz);
+    std::shared_ptr<AllocatedFrame> scaledYu12Buf;
+    if (it != mScaledYu12Frames.end()) {
+        scaledYu12Buf = it->second;
+    } else {
+        it = mIntermediateBuffers.find(outSz);
+        if (it == mIntermediateBuffers.end()) {
+            ALOGE("%s: failed to find intermediate buffer size %dx%d", __FUNCTION__, outSz.width,
+                  outSz.height);
+            return -1;
+        }
+        scaledYu12Buf = it->second;
+    }
+    // Scale
+    YCbCrLayout outLayout;
+    ret = scaledYu12Buf->getLayout(&outLayout);
+    if (ret != 0) {
+        ALOGE("%s: failed to get output buffer layout", __FUNCTION__);
+        return ret;
+    }
+
+    ret = libyuv::I420Scale(
+            static_cast<uint8_t*>(croppedLayout.y), croppedLayout.yStride,
+            static_cast<uint8_t*>(croppedLayout.cb), croppedLayout.cStride,
+            static_cast<uint8_t*>(croppedLayout.cr), croppedLayout.cStride, inputCrop.width,
+            inputCrop.height, static_cast<uint8_t*>(outLayout.y), outLayout.yStride,
+            static_cast<uint8_t*>(outLayout.cb), outLayout.cStride,
+            static_cast<uint8_t*>(outLayout.cr), outLayout.cStride, outSz.width, outSz.height,
+            // TODO: b/72261744 see if we can use better filter without losing too much perf
+            libyuv::FilterMode::kFilterNone);
+
+    if (ret != 0) {
+        ALOGE("%s: failed to scale buffer from %dx%d to %dx%d. Ret %d", __FUNCTION__,
+              inputCrop.width, inputCrop.height, outSz.width, outSz.height, ret);
+        return ret;
+    }
+
+    *out = outLayout;
+    mScaledYu12Frames.insert({outSz, scaledYu12Buf});
+    return 0;
+}
+
+int ExternalCameraDeviceSession::OutputThread::cropAndScaleThumbLocked(
+        std::shared_ptr<AllocatedFrame>& in, const Size& outSz, YCbCrLayout* out) {
+    Size inSz{in->mWidth, in->mHeight};
+
+    if ((outSz.width * outSz.height) > (mYu12ThumbFrame->mWidth * mYu12ThumbFrame->mHeight)) {
+        ALOGE("%s: Requested thumbnail size too big (%d,%d) > (%d,%d)", __FUNCTION__, outSz.width,
+              outSz.height, mYu12ThumbFrame->mWidth, mYu12ThumbFrame->mHeight);
+        return -1;
+    }
+
+    int ret;
+
+    /* This will crop-and-zoom the input YUV frame to the thumbnail size
+     * Based on the following logic:
+     *  1) Square pixels come in, square pixels come out, therefore single
+     *  scale factor is computed to either make input bigger or smaller
+     *  depending on if we are upscaling or downscaling
+     *  2) That single scale factor would either make height too tall or width
+     *  too wide so we need to crop the input either horizontally or vertically
+     *  but not both
+     */
+
+    /* Convert the input and output dimensions into floats for ease of math */
+    float fWin = static_cast<float>(inSz.width);
+    float fHin = static_cast<float>(inSz.height);
+    float fWout = static_cast<float>(outSz.width);
+    float fHout = static_cast<float>(outSz.height);
+
+    /* Compute the one scale factor from (1) above, it will be the smaller of
+     * the two possibilities. */
+    float scaleFactor = std::min(fHin / fHout, fWin / fWout);
+
+    /* Since we are crop-and-zooming (as opposed to letter/pillar boxing) we can
+     * simply multiply the output by our scaleFactor to get the cropped input
+     * size. Note that at least one of {fWcrop, fHcrop} is going to wind up
+     * being {fWin, fHin} respectively because fHout or fWout cancels out the
+     * scaleFactor calculation above.
+     *
+     * Specifically:
+     *  if ( fHin / fHout ) < ( fWin / fWout ) we crop the sides off
+     * input, in which case
+     *    scaleFactor = fHin / fHout
+     *    fWcrop = fHin / fHout * fWout
+     *    fHcrop = fHin
+     *
+     * Note that fWcrop <= fWin ( because ( fHin / fHout ) * fWout < fWin, which
+     * is just the inequality above with both sides multiplied by fWout
+     *
+     * on the other hand if ( fWin / fWout ) < ( fHin / fHout) we crop the top
+     * and the bottom off of input, and
+     *    scaleFactor = fWin / fWout
+     *    fWcrop = fWin
+     *    fHCrop = fWin / fWout * fHout
+     */
+    float fWcrop = scaleFactor * fWout;
+    float fHcrop = scaleFactor * fHout;
+
+    /* Convert to integer and truncate to an even number */
+    Size cropSz = {.width = 2 * static_cast<int32_t>(fWcrop / 2.0f),
+                   .height = 2 * static_cast<int32_t>(fHcrop / 2.0f)};
+
+    /* Convert to a centered rectange with even top/left */
+    IMapper::Rect inputCrop{.left = 2 * static_cast<int32_t>((inSz.width - cropSz.width) / 4),
+                            .top = 2 * static_cast<int32_t>((inSz.height - cropSz.height) / 4),
+                            .width = static_cast<int32_t>(cropSz.width),
+                            .height = static_cast<int32_t>(cropSz.height)};
+
+    if ((inputCrop.top < 0) || (inputCrop.top >= static_cast<int32_t>(inSz.height)) ||
+        (inputCrop.left < 0) || (inputCrop.left >= static_cast<int32_t>(inSz.width)) ||
+        (inputCrop.width <= 0) ||
+        (inputCrop.width + inputCrop.left > static_cast<int32_t>(inSz.width)) ||
+        (inputCrop.height <= 0) ||
+        (inputCrop.height + inputCrop.top > static_cast<int32_t>(inSz.height))) {
+        ALOGE("%s: came up with really wrong crop rectangle", __FUNCTION__);
+        ALOGE("%s: input layout %dx%d to for output size %dx%d", __FUNCTION__, inSz.width,
+              inSz.height, outSz.width, outSz.height);
+        ALOGE("%s: computed input crop +%d,+%d %dx%d", __FUNCTION__, inputCrop.left, inputCrop.top,
+              inputCrop.width, inputCrop.height);
+        return -1;
+    }
+
+    YCbCrLayout inputLayout;
+    ret = in->getCroppedLayout(inputCrop, &inputLayout);
+    if (ret != 0) {
+        ALOGE("%s: failed to crop input layout %dx%d to for output size %dx%d", __FUNCTION__,
+              inSz.width, inSz.height, outSz.width, outSz.height);
+        ALOGE("%s: computed input crop +%d,+%d %dx%d", __FUNCTION__, inputCrop.left, inputCrop.top,
+              inputCrop.width, inputCrop.height);
+        return ret;
+    }
+    ALOGV("%s: crop input layout %dx%d to for output size %dx%d", __FUNCTION__, inSz.width,
+          inSz.height, outSz.width, outSz.height);
+    ALOGV("%s: computed input crop +%d,+%d %dx%d", __FUNCTION__, inputCrop.left, inputCrop.top,
+          inputCrop.width, inputCrop.height);
+
+    // Scale
+    YCbCrLayout outFullLayout;
+
+    ret = mYu12ThumbFrame->getLayout(&outFullLayout);
+    if (ret != 0) {
+        ALOGE("%s: failed to get output buffer layout", __FUNCTION__);
+        return ret;
+    }
+
+    ret = libyuv::I420Scale(static_cast<uint8_t*>(inputLayout.y), inputLayout.yStride,
+                            static_cast<uint8_t*>(inputLayout.cb), inputLayout.cStride,
+                            static_cast<uint8_t*>(inputLayout.cr), inputLayout.cStride,
+                            inputCrop.width, inputCrop.height,
+                            static_cast<uint8_t*>(outFullLayout.y), outFullLayout.yStride,
+                            static_cast<uint8_t*>(outFullLayout.cb), outFullLayout.cStride,
+                            static_cast<uint8_t*>(outFullLayout.cr), outFullLayout.cStride,
+                            outSz.width, outSz.height, libyuv::FilterMode::kFilterNone);
+
+    if (ret != 0) {
+        ALOGE("%s: failed to scale buffer from %dx%d to %dx%d. Ret %d", __FUNCTION__,
+              inputCrop.width, inputCrop.height, outSz.width, outSz.height, ret);
+        return ret;
+    }
+
+    *out = outFullLayout;
+    return 0;
+}
+
+int ExternalCameraDeviceSession::OutputThread::createJpegLocked(
+        HalStreamBuffer& halBuf, const common::V1_0::helper::CameraMetadata& setting) {
+    ATRACE_CALL();
+    int ret;
+    auto lfail = [&](auto... args) {
+        ALOGE(args...);
+
+        return 1;
+    };
+    auto parent = mParent.lock();
+    if (parent == nullptr) {
+        ALOGE("%s: session has been disconnected!", __FUNCTION__);
+        return 1;
+    }
+
+    ALOGV("%s: HAL buffer sid: %d bid: %" PRIu64 " w: %u h: %u", __FUNCTION__, halBuf.streamId,
+          static_cast<uint64_t>(halBuf.bufferId), halBuf.width, halBuf.height);
+    ALOGV("%s: HAL buffer fmt: %x usage: %" PRIx64 " ptr: %p", __FUNCTION__, halBuf.format,
+          static_cast<uint64_t>(halBuf.usage), halBuf.bufPtr);
+    ALOGV("%s: YV12 buffer %d x %d", __FUNCTION__, mYu12Frame->mWidth, mYu12Frame->mHeight);
+
+    int jpegQuality, thumbQuality;
+    Size thumbSize;
+    bool outputThumbnail = true;
+
+    if (setting.exists(ANDROID_JPEG_QUALITY)) {
+        camera_metadata_ro_entry entry = setting.find(ANDROID_JPEG_QUALITY);
+        jpegQuality = entry.data.u8[0];
+    } else {
+        return lfail("%s: ANDROID_JPEG_QUALITY not set", __FUNCTION__);
+    }
+
+    if (setting.exists(ANDROID_JPEG_THUMBNAIL_QUALITY)) {
+        camera_metadata_ro_entry entry = setting.find(ANDROID_JPEG_THUMBNAIL_QUALITY);
+        thumbQuality = entry.data.u8[0];
+    } else {
+        return lfail("%s: ANDROID_JPEG_THUMBNAIL_QUALITY not set", __FUNCTION__);
+    }
+
+    if (setting.exists(ANDROID_JPEG_THUMBNAIL_SIZE)) {
+        camera_metadata_ro_entry entry = setting.find(ANDROID_JPEG_THUMBNAIL_SIZE);
+        thumbSize = Size{.width = entry.data.i32[0], .height = entry.data.i32[1]};
+        if (thumbSize.width == 0 && thumbSize.height == 0) {
+            outputThumbnail = false;
+        }
+    } else {
+        return lfail("%s: ANDROID_JPEG_THUMBNAIL_SIZE not set", __FUNCTION__);
+    }
+
+    /* Cropped and scaled YU12 buffer for main and thumbnail */
+    YCbCrLayout yu12Main;
+    Size jpegSize{halBuf.width, halBuf.height};
+
+    /* Compute temporary buffer sizes accounting for the following:
+     * thumbnail can't exceed APP1 size of 64K
+     * main image needs to hold APP1, headers, and at most a poorly
+     * compressed image */
+    const ssize_t maxThumbCodeSize = 64 * 1024;
+    const ssize_t maxJpegCodeSize =
+            mBlobBufferSize == 0 ? parent->getJpegBufferSize(jpegSize.width, jpegSize.height)
+                                 : mBlobBufferSize;
+
+    /* Check that getJpegBufferSize did not return an error */
+    if (maxJpegCodeSize < 0) {
+        return lfail("%s: getJpegBufferSize returned %zd", __FUNCTION__, maxJpegCodeSize);
+    }
+
+    /* Hold actual thumbnail and main image code sizes */
+    size_t thumbCodeSize = 0, jpegCodeSize = 0;
+    /* Temporary thumbnail code buffer */
+    std::vector<uint8_t> thumbCode(outputThumbnail ? maxThumbCodeSize : 0);
+
+    YCbCrLayout yu12Thumb;
+    if (outputThumbnail) {
+        ret = cropAndScaleThumbLocked(mYu12Frame, thumbSize, &yu12Thumb);
+
+        if (ret != 0) {
+            return lfail("%s: crop and scale thumbnail failed!", __FUNCTION__);
+        }
+    }
+
+    /* Scale and crop main jpeg */
+    ret = cropAndScaleLocked(mYu12Frame, jpegSize, &yu12Main);
+
+    if (ret != 0) {
+        return lfail("%s: crop and scale main failed!", __FUNCTION__);
+    }
+
+    /* Encode the thumbnail image */
+    if (outputThumbnail) {
+        ret = encodeJpegYU12(thumbSize, yu12Thumb, thumbQuality, 0, 0, &thumbCode[0],
+                             maxThumbCodeSize, thumbCodeSize);
+
+        if (ret != 0) {
+            return lfail("%s: thumbnail encodeJpegYU12 failed with %d", __FUNCTION__, ret);
+        }
+    }
+
+    /* Combine camera characteristics with request settings to form EXIF
+     * metadata */
+    common::V1_0::helper::CameraMetadata meta(mCameraCharacteristics);
+    meta.append(setting);
+
+    /* Generate EXIF object */
+    std::unique_ptr<ExifUtils> utils(ExifUtils::create());
+    /* Make sure it's initialized */
+    utils->initialize();
+
+    utils->setFromMetadata(meta, jpegSize.width, jpegSize.height);
+    utils->setMake(mExifMake);
+    utils->setModel(mExifModel);
+
+    ret = utils->generateApp1(outputThumbnail ? &thumbCode[0] : nullptr, thumbCodeSize);
+
+    if (!ret) {
+        return lfail("%s: generating APP1 failed", __FUNCTION__);
+    }
+
+    /* Get internal buffer */
+    size_t exifDataSize = utils->getApp1Length();
+    const uint8_t* exifData = utils->getApp1Buffer();
+
+    /* Lock the HAL jpeg code buffer */
+    void* bufPtr = sHandleImporter.lock(*(halBuf.bufPtr), static_cast<uint64_t>(halBuf.usage),
+                                        maxJpegCodeSize);
+
+    if (!bufPtr) {
+        return lfail("%s: could not lock %zu bytes", __FUNCTION__, maxJpegCodeSize);
+    }
+
+    /* Encode the main jpeg image */
+    ret = encodeJpegYU12(jpegSize, yu12Main, jpegQuality, exifData, exifDataSize, bufPtr,
+                         maxJpegCodeSize, jpegCodeSize);
+
+    /* TODO: Not sure this belongs here, maybe better to pass jpegCodeSize out
+     * and do this when returning buffer to parent */
+    CameraBlob blob{CameraBlobId::JPEG, static_cast<int32_t>(jpegCodeSize)};
+    void* blobDst = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(bufPtr) + maxJpegCodeSize -
+                                            sizeof(CameraBlob));
+    memcpy(blobDst, &blob, sizeof(CameraBlob));
+
+    /* Unlock the HAL jpeg code buffer */
+    int relFence = sHandleImporter.unlock(*(halBuf.bufPtr));
+    if (relFence >= 0) {
+        halBuf.acquireFence = relFence;
+    }
+
+    /* Check if our JPEG actually succeeded */
+    if (ret != 0) {
+        return lfail("%s: encodeJpegYU12 failed with %d", __FUNCTION__, ret);
+    }
+
+    ALOGV("%s: encoded JPEG (ret:%d) with Q:%d max size: %zu", __FUNCTION__, ret, jpegQuality,
+          maxJpegCodeSize);
+
+    return 0;
+}
+
+void ExternalCameraDeviceSession::OutputThread::clearIntermediateBuffers() {
+    std::lock_guard<std::mutex> lk(mBufferLock);
+    mYu12Frame.reset();
+    mYu12ThumbFrame.reset();
+    mIntermediateBuffers.clear();
+    mMuteTestPatternFrame.clear();
+    mBlobBufferSize = 0;
+}
+
+bool ExternalCameraDeviceSession::OutputThread::threadLoop() {
+    std::shared_ptr<HalRequest> req;
+    auto parent = mParent.lock();
+    if (parent == nullptr) {
+        ALOGE("%s: session has been disconnected!", __FUNCTION__);
+        return false;
+    }
+
+    // TODO: maybe we need to setup a sensor thread to dq/enq v4l frames
+    //       regularly to prevent v4l buffer queue filled with stale buffers
+    //       when app doesn't program a preview request
+    waitForNextRequest(&req);
+    if (req == nullptr) {
+        // No new request, wait again
+        return true;
+    }
+
+    auto onDeviceError = [&](auto... args) {
+        ALOGE(args...);
+        parent->notifyError(req->frameNumber, /*stream*/ -1, ErrorCode::ERROR_DEVICE);
+        signalRequestDone();
+        return false;
+    };
+
+    if (req->frameIn->mFourcc != V4L2_PIX_FMT_MJPEG && req->frameIn->mFourcc != V4L2_PIX_FMT_Z16) {
+        return onDeviceError("%s: do not support V4L2 format %c%c%c%c", __FUNCTION__,
+                             req->frameIn->mFourcc & 0xFF, (req->frameIn->mFourcc >> 8) & 0xFF,
+                             (req->frameIn->mFourcc >> 16) & 0xFF,
+                             (req->frameIn->mFourcc >> 24) & 0xFF);
+    }
+
+    int res = requestBufferStart(req->buffers);
+    if (res != 0) {
+        ALOGE("%s: send BufferRequest failed! res %d", __FUNCTION__, res);
+        return onDeviceError("%s: failed to send buffer request!", __FUNCTION__);
+    }
+
+    std::unique_lock<std::mutex> lk(mBufferLock);
+    // Convert input V4L2 frame to YU12 of the same size
+    // TODO: see if we can save some computation by converting to YV12 here
+    uint8_t* inData;
+    size_t inDataSize;
+    if (req->frameIn->getData(&inData, &inDataSize) != 0) {
+        lk.unlock();
+        return onDeviceError("%s: V4L2 buffer map failed", __FUNCTION__);
+    }
+
+    // Process camera mute state
+    auto testPatternMode = req->setting.find(ANDROID_SENSOR_TEST_PATTERN_MODE);
+    if (testPatternMode.count == 1) {
+        if (mCameraMuted != (testPatternMode.data.u8[0] != ANDROID_SENSOR_TEST_PATTERN_MODE_OFF)) {
+            mCameraMuted = !mCameraMuted;
+            // Get solid color for test pattern, if any was set
+            if (testPatternMode.data.u8[0] == ANDROID_SENSOR_TEST_PATTERN_MODE_SOLID_COLOR) {
+                auto entry = req->setting.find(ANDROID_SENSOR_TEST_PATTERN_DATA);
+                if (entry.count == 4) {
+                    // Update the mute frame if the pattern color has changed
+                    if (memcmp(entry.data.i32, mTestPatternData, sizeof(mTestPatternData)) != 0) {
+                        memcpy(mTestPatternData, entry.data.i32, sizeof(mTestPatternData));
+                        // Fill the mute frame with the solid color, use only 8 MSB of RGGB as RGB
+                        for (int i = 0; i < mMuteTestPatternFrame.size(); i += 3) {
+                            mMuteTestPatternFrame[i] = entry.data.i32[0] >> 24;
+                            mMuteTestPatternFrame[i + 1] = entry.data.i32[1] >> 24;
+                            mMuteTestPatternFrame[i + 2] = entry.data.i32[3] >> 24;
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    // TODO: in some special case maybe we can decode jpg directly to gralloc output?
+    if (req->frameIn->mFourcc == V4L2_PIX_FMT_MJPEG) {
+        ATRACE_BEGIN("MJPGtoI420");
+        res = 0;
+        if (mCameraMuted) {
+            res = libyuv::ConvertToI420(
+                    mMuteTestPatternFrame.data(), mMuteTestPatternFrame.size(),
+                    static_cast<uint8_t*>(mYu12FrameLayout.y), mYu12FrameLayout.yStride,
+                    static_cast<uint8_t*>(mYu12FrameLayout.cb), mYu12FrameLayout.cStride,
+                    static_cast<uint8_t*>(mYu12FrameLayout.cr), mYu12FrameLayout.cStride, 0, 0,
+                    mYu12Frame->mWidth, mYu12Frame->mHeight, mYu12Frame->mWidth,
+                    mYu12Frame->mHeight, libyuv::kRotate0, libyuv::FOURCC_RAW);
+        } else {
+            res = libyuv::MJPGToI420(
+                    inData, inDataSize, static_cast<uint8_t*>(mYu12FrameLayout.y),
+                    mYu12FrameLayout.yStride, static_cast<uint8_t*>(mYu12FrameLayout.cb),
+                    mYu12FrameLayout.cStride, static_cast<uint8_t*>(mYu12FrameLayout.cr),
+                    mYu12FrameLayout.cStride, mYu12Frame->mWidth, mYu12Frame->mHeight,
+                    mYu12Frame->mWidth, mYu12Frame->mHeight);
+        }
+        ATRACE_END();
+
+        if (res != 0) {
+            // For some webcam, the first few V4L2 frames might be malformed...
+            ALOGE("%s: Convert V4L2 frame to YU12 failed! res %d", __FUNCTION__, res);
+            lk.unlock();
+            Status st = parent->processCaptureRequestError(req);
+            if (st != Status::OK) {
+                return onDeviceError("%s: failed to process capture request error!", __FUNCTION__);
+            }
+            signalRequestDone();
+            return true;
+        }
+    }
+
+    ATRACE_BEGIN("Wait for BufferRequest done");
+    res = waitForBufferRequestDone(&req->buffers);
+    ATRACE_END();
+
+    if (res != 0) {
+        ALOGE("%s: wait for BufferRequest done failed! res %d", __FUNCTION__, res);
+        lk.unlock();
+        return onDeviceError("%s: failed to process buffer request error!", __FUNCTION__);
+    }
+
+    ALOGV("%s processing new request", __FUNCTION__);
+    const int kSyncWaitTimeoutMs = 500;
+    for (auto& halBuf : req->buffers) {
+        if (*(halBuf.bufPtr) == nullptr) {
+            ALOGW("%s: buffer for stream %d missing", __FUNCTION__, halBuf.streamId);
+            halBuf.fenceTimeout = true;
+        } else if (halBuf.acquireFence >= 0) {
+            int ret = sync_wait(halBuf.acquireFence, kSyncWaitTimeoutMs);
+            if (ret) {
+                halBuf.fenceTimeout = true;
+            } else {
+                ::close(halBuf.acquireFence);
+                halBuf.acquireFence = -1;
+            }
+        }
+
+        if (halBuf.fenceTimeout) {
+            continue;
+        }
+
+        // Gralloc lockYCbCr the buffer
+        switch (halBuf.format) {
+            case PixelFormat::BLOB: {
+                int ret = createJpegLocked(halBuf, req->setting);
+
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: createJpegLocked failed with %d", __FUNCTION__, ret);
+                }
+            } break;
+            case PixelFormat::Y16: {
+                void* outLayout = sHandleImporter.lock(
+                        *(halBuf.bufPtr), static_cast<uint64_t>(halBuf.usage), inDataSize);
+
+                std::memcpy(outLayout, inData, inDataSize);
+
+                int relFence = sHandleImporter.unlock(*(halBuf.bufPtr));
+                if (relFence >= 0) {
+                    halBuf.acquireFence = relFence;
+                }
+            } break;
+            case PixelFormat::YCBCR_420_888:
+            case PixelFormat::YV12: {
+                IMapper::Rect outRect{0, 0, static_cast<int32_t>(halBuf.width),
+                                      static_cast<int32_t>(halBuf.height)};
+                YCbCrLayout outLayout = sHandleImporter.lockYCbCr(
+                        *(halBuf.bufPtr), static_cast<uint64_t>(halBuf.usage), outRect);
+                ALOGV("%s: outLayout y %p cb %p cr %p y_str %d c_str %d c_step %d", __FUNCTION__,
+                      outLayout.y, outLayout.cb, outLayout.cr, outLayout.yStride, outLayout.cStride,
+                      outLayout.chromaStep);
+
+                // Convert to output buffer size/format
+                uint32_t outputFourcc = getFourCcFromLayout(outLayout);
+                ALOGV("%s: converting to format %c%c%c%c", __FUNCTION__, outputFourcc & 0xFF,
+                      (outputFourcc >> 8) & 0xFF, (outputFourcc >> 16) & 0xFF,
+                      (outputFourcc >> 24) & 0xFF);
+
+                YCbCrLayout cropAndScaled;
+                ATRACE_BEGIN("cropAndScaleLocked");
+                int ret = cropAndScaleLocked(mYu12Frame, Size{halBuf.width, halBuf.height},
+                                             &cropAndScaled);
+                ATRACE_END();
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: crop and scale failed!", __FUNCTION__);
+                }
+
+                Size sz{halBuf.width, halBuf.height};
+                ATRACE_BEGIN("formatConvert");
+                ret = formatConvert(cropAndScaled, outLayout, sz, outputFourcc);
+                ATRACE_END();
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: format conversion failed!", __FUNCTION__);
+                }
+                int relFence = sHandleImporter.unlock(*(halBuf.bufPtr));
+                if (relFence >= 0) {
+                    halBuf.acquireFence = relFence;
+                }
+            } break;
+            default:
+                lk.unlock();
+                return onDeviceError("%s: unknown output format %x", __FUNCTION__, halBuf.format);
+        }
+    }  // for each buffer
+    mScaledYu12Frames.clear();
+
+    // Don't hold the lock while calling back to parent
+    lk.unlock();
+    Status st = parent->processCaptureResult(req);
+    if (st != Status::OK) {
+        return onDeviceError("%s: failed to process capture result!", __FUNCTION__);
+    }
+    signalRequestDone();
+    return true;
+}
+
+// End ExternalCameraDeviceSession::OutputThread functions
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
diff --git a/camera/device/default/ExternalCameraDeviceSession.h b/camera/device/default/ExternalCameraDeviceSession.h
new file mode 100644
index 0000000..5d42092
--- /dev/null
+++ b/camera/device/default/ExternalCameraDeviceSession.h
@@ -0,0 +1,399 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICESESSION_H_
+#define HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICESESSION_H_
+
+#include <ExternalCameraUtils.h>
+#include <SimpleThread.h>
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <aidl/android/hardware/camera/device/BnCameraDeviceSession.h>
+#include <aidl/android/hardware/camera/device/BufferRequest.h>
+#include <aidl/android/hardware/camera/device/Stream.h>
+#include <android-base/unique_fd.h>
+#include <fmq/AidlMessageQueue.h>
+#include <utils/Thread.h>
+#include <deque>
+#include <list>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::Status;
+using ::aidl::android::hardware::camera::device::BnCameraDeviceSession;
+using ::aidl::android::hardware::camera::device::BufferCache;
+using ::aidl::android::hardware::camera::device::BufferRequest;
+using ::aidl::android::hardware::camera::device::CameraMetadata;
+using ::aidl::android::hardware::camera::device::CameraOfflineSessionInfo;
+using ::aidl::android::hardware::camera::device::CaptureRequest;
+using ::aidl::android::hardware::camera::device::HalStream;
+using ::aidl::android::hardware::camera::device::ICameraDeviceCallback;
+using ::aidl::android::hardware::camera::device::ICameraOfflineSession;
+using ::aidl::android::hardware::camera::device::RequestTemplate;
+using ::aidl::android::hardware::camera::device::Stream;
+using ::aidl::android::hardware::camera::device::StreamConfiguration;
+using ::aidl::android::hardware::common::fmq::MQDescriptor;
+using ::aidl::android::hardware::common::fmq::SynchronizedReadWrite;
+using ::android::AidlMessageQueue;
+using ::android::base::unique_fd;
+using ::android::hardware::camera::common::helper::SimpleThread;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+using ::android::hardware::camera::external::common::SizeHasher;
+using ::ndk::ScopedAStatus;
+
+class ExternalCameraDeviceSession : public BnCameraDeviceSession, public OutputThreadInterface {
+  public:
+    ExternalCameraDeviceSession(const std::shared_ptr<ICameraDeviceCallback>&,
+                                const ExternalCameraConfig& cfg,
+                                const std::vector<SupportedV4L2Format>& sortedFormats,
+                                const CroppingType& croppingType,
+                                const common::V1_0::helper::CameraMetadata& chars,
+                                const std::string& cameraId, unique_fd v4l2Fd);
+    ~ExternalCameraDeviceSession() override;
+
+    // Caller must use this method to check if CameraDeviceSession ctor failed
+    bool isInitFailed();
+    bool isClosed();
+
+    ScopedAStatus close() override;
+
+    ScopedAStatus configureStreams(const StreamConfiguration& in_requestedConfiguration,
+                                   std::vector<HalStream>* _aidl_return) override;
+    ScopedAStatus constructDefaultRequestSettings(RequestTemplate in_type,
+                                                  CameraMetadata* _aidl_return) override;
+    ScopedAStatus flush() override;
+    ScopedAStatus getCaptureRequestMetadataQueue(
+            MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) override;
+    ScopedAStatus getCaptureResultMetadataQueue(
+            MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) override;
+    ScopedAStatus isReconfigurationRequired(const CameraMetadata& in_oldSessionParams,
+                                            const CameraMetadata& in_newSessionParams,
+                                            bool* _aidl_return) override;
+    ScopedAStatus processCaptureRequest(const std::vector<CaptureRequest>& in_requests,
+                                        const std::vector<BufferCache>& in_cachesToRemove,
+                                        int32_t* _aidl_return) override;
+    ScopedAStatus signalStreamFlush(const std::vector<int32_t>& in_streamIds,
+                                    int32_t in_streamConfigCounter) override;
+    ScopedAStatus switchToOffline(const std::vector<int32_t>& in_streamsToKeep,
+                                  CameraOfflineSessionInfo* out_offlineSessionInfo,
+                                  std::shared_ptr<ICameraOfflineSession>* _aidl_return) override;
+    ScopedAStatus repeatingRequestEnd(int32_t in_frameNumber,
+                                      const std::vector<int32_t>& in_streamIds) override;
+
+    Status importBuffer(int32_t streamId, uint64_t bufId, buffer_handle_t buf,
+                        buffer_handle_t** outBufPtr) override;
+
+    void notifyError(int32_t frameNumber, int32_t streamId, ErrorCode ec) override;
+
+    Status processCaptureRequestError(const std::shared_ptr<HalRequest>& ptr,
+                                      std::vector<NotifyMsg>* msgs,
+                                      std::vector<CaptureResult>* results) override;
+
+    Status processCaptureResult(std::shared_ptr<HalRequest>& ptr) override;
+    ssize_t getJpegBufferSize(int32_t width, int32_t height) const override;
+
+    // Called by CameraDevice to dump active device states
+    binder_status_t dump(int fd, const char** args, uint32_t numArgs) override;
+
+    static Status isStreamCombinationSupported(
+            const StreamConfiguration& config,
+            const std::vector<SupportedV4L2Format>& supportedFormats,
+            const ExternalCameraConfig& devCfg);
+
+    static const int kMaxProcessedStream = 2;
+    static const int kMaxStallStream = 1;
+    static const uint32_t kMaxBytesPerPixel = 2;
+
+    class BufferRequestThread : public SimpleThread {
+      public:
+        BufferRequestThread(std::weak_ptr<OutputThreadInterface> parent,
+                            std::shared_ptr<ICameraDeviceCallback> callbacks);
+
+        int requestBufferStart(const std::vector<HalStreamBuffer>&);
+        int waitForBufferRequestDone(
+                /*out*/ std::vector<HalStreamBuffer>*);
+
+        bool threadLoop() override;
+
+      private:
+        void waitForNextRequest();
+
+        const std::weak_ptr<OutputThreadInterface> mParent;
+        const std::shared_ptr<ICameraDeviceCallback> mCallbacks;
+
+        std::mutex mLock;
+        bool mRequestingBuffer = false;
+
+        std::vector<HalStreamBuffer> mBufferReqs;
+        std::vector<HalStreamBuffer> mPendingReturnBufferReqs;
+        // mHalBufferReqs is not under mLock protection during the HIDL transaction
+        std::vector<BufferRequest> mHalBufferReqs;
+
+        // request buffers takes much less time in steady state, but can take much longer
+        // when requesting 1st buffer from a stream.
+        // TODO: consider a separate timeout for new vs. steady state?
+        // TODO: or make sure framework is warming up the pipeline during configure new stream?
+        static const int kReqProcTimeoutMs = 66;
+
+        static const int kReqWaitTimeoutMs = 33;
+        static const int kReqWaitTimesWarn = 90;   // 33ms * 90 ~= 3 sec
+        std::condition_variable mRequestCond;      // signaled when a new buffer request incoming
+        std::condition_variable mRequestDoneCond;  // signaled when a request is done
+    };
+
+    class OutputThread : public SimpleThread {
+      public:
+        OutputThread(std::weak_ptr<OutputThreadInterface> parent, CroppingType,
+                     const common::V1_0::helper::CameraMetadata&,
+                     std::shared_ptr<BufferRequestThread> bufReqThread);
+        ~OutputThread();
+
+        Status allocateIntermediateBuffers(const Size& v4lSize, const Size& thumbSize,
+                                           const std::vector<Stream>& streams,
+                                           uint32_t blobBufferSize);
+        Status submitRequest(const std::shared_ptr<HalRequest>&);
+        void flush();
+        void dump(int fd);
+        bool threadLoop() override;
+
+        void setExifMakeModel(const std::string& make, const std::string& model);
+
+        // The remaining request list is returned for offline processing
+        std::list<std::shared_ptr<HalRequest>> switchToOffline();
+
+      protected:
+        static const int kFlushWaitTimeoutSec = 3;  // 3 sec
+        static const int kReqWaitTimeoutMs = 33;    // 33ms
+        static const int kReqWaitTimesMax = 90;     // 33ms * 90 ~= 3 sec
+
+        // Methods to request output buffer in parallel
+        int requestBufferStart(const std::vector<HalStreamBuffer>&);
+        int waitForBufferRequestDone(
+                /*out*/ std::vector<HalStreamBuffer>*);
+
+        void waitForNextRequest(std::shared_ptr<HalRequest>* out);
+        void signalRequestDone();
+
+        int cropAndScaleLocked(std::shared_ptr<AllocatedFrame>& in, const Size& outSize,
+                               YCbCrLayout* out);
+
+        int cropAndScaleThumbLocked(std::shared_ptr<AllocatedFrame>& in, const Size& outSize,
+                                    YCbCrLayout* out);
+
+        int createJpegLocked(HalStreamBuffer& halBuf,
+                             const common::V1_0::helper::CameraMetadata& settings);
+
+        void clearIntermediateBuffers();
+
+        const std::weak_ptr<OutputThreadInterface> mParent;
+        const CroppingType mCroppingType;
+        const common::V1_0::helper::CameraMetadata mCameraCharacteristics;
+
+        mutable std::mutex mRequestListLock;       // Protect access to mRequestList,
+                                                   // mProcessingRequest and mProcessingFrameNumber
+        std::condition_variable mRequestCond;      // signaled when a new request is submitted
+        std::condition_variable mRequestDoneCond;  // signaled when a request is done processing
+        std::list<std::shared_ptr<HalRequest>> mRequestList;
+        bool mProcessingRequest = false;
+        uint32_t mProcessingFrameNumber = 0;
+
+        // V4L2 frameIn
+        // (MJPG decode)-> mYu12Frame
+        // (Scale)-> mScaledYu12Frames
+        // (Format convert) -> output gralloc frames
+        mutable std::mutex mBufferLock;  // Protect access to intermediate buffers
+        std::shared_ptr<AllocatedFrame> mYu12Frame;
+        std::shared_ptr<AllocatedFrame> mYu12ThumbFrame;
+        std::unordered_map<Size, std::shared_ptr<AllocatedFrame>, SizeHasher> mIntermediateBuffers;
+        std::unordered_map<Size, std::shared_ptr<AllocatedFrame>, SizeHasher> mScaledYu12Frames;
+        YCbCrLayout mYu12FrameLayout;
+        YCbCrLayout mYu12ThumbFrameLayout;
+        std::vector<uint8_t> mMuteTestPatternFrame;
+        uint32_t mTestPatternData[4] = {0, 0, 0, 0};
+        bool mCameraMuted = false;
+        uint32_t mBlobBufferSize = 0;  // 0 -> HAL derive buffer size, else: use given size
+
+        std::string mExifMake;
+        std::string mExifModel;
+
+        const std::shared_ptr<BufferRequestThread> mBufferRequestThread;
+    };
+
+  private:
+    bool initialize();
+    // To init/close different version of output thread
+    void initOutputThread();
+    void closeOutputThread();
+    void closeOutputThreadImpl();
+
+    void close(bool callerIsDtor);
+    Status initStatus() const;
+    status_t initDefaultRequests();
+
+    status_t fillCaptureResult(common::V1_0::helper::CameraMetadata& md, nsecs_t timestamp);
+    int configureV4l2StreamLocked(const SupportedV4L2Format& fmt, double fps = 0.0);
+    int v4l2StreamOffLocked();
+
+    int setV4l2FpsLocked(double fps);
+
+    std::unique_ptr<V4L2Frame> dequeueV4l2FrameLocked(
+            /*out*/ nsecs_t* shutterTs);  // Called with mLock held
+
+    void enqueueV4l2Frame(const std::shared_ptr<V4L2Frame>&);
+
+    // Check if input Stream is one of supported stream setting on this device
+    static bool isSupported(const Stream& stream,
+                            const std::vector<SupportedV4L2Format>& supportedFormats,
+                            const ExternalCameraConfig& cfg);
+
+    // Validate and import request's output buffers and acquire fence
+    Status importRequestLocked(const CaptureRequest& request,
+                               std::vector<buffer_handle_t*>& allBufPtrs,
+                               std::vector<int>& allFences);
+
+    Status importRequestLockedImpl(const CaptureRequest& request,
+                                   std::vector<buffer_handle_t*>& allBufPtrs,
+                                   std::vector<int>& allFences);
+
+    Status importBufferLocked(int32_t streamId, uint64_t bufId, buffer_handle_t buf,
+                              /*out*/ buffer_handle_t** outBufPtr);
+    static void cleanupInflightFences(std::vector<int>& allFences, size_t numFences);
+    void cleanupBuffersLocked(int id);
+
+    void updateBufferCaches(const std::vector<BufferCache>& cachesToRemove);
+
+    Status processOneCaptureRequest(const CaptureRequest& request);
+    void notifyShutter(int32_t frameNumber, nsecs_t shutterTs);
+
+    void invokeProcessCaptureResultCallback(std::vector<CaptureResult>& results, bool tryWriteFmq);
+    Size getMaxJpegResolution() const;
+
+    Size getMaxThumbResolution() const;
+
+    int waitForV4L2BufferReturnLocked(std::unique_lock<std::mutex>& lk);
+
+    // Main body of switchToOffline. This method does not invoke any callbacks
+    // but instead returns the necessary callbacks in output arguments so callers
+    // can callback later without holding any locks
+    Status switchToOffline(const std::vector<int32_t>& offlineStreams,
+                           /*out*/ std::vector<NotifyMsg>* msgs,
+                           /*out*/ std::vector<CaptureResult>* results,
+                           /*out*/ CameraOfflineSessionInfo* info,
+                           /*out*/ std::shared_ptr<ICameraOfflineSession>* session);
+
+    bool supportOfflineLocked(int32_t streamId);
+
+    // Whether a request can be completely dropped when switching to offline
+    bool canDropRequest(const std::vector<int32_t>& offlineStreams,
+                        std::shared_ptr<HalRequest> halReq);
+
+    void fillOfflineSessionInfo(const std::vector<int32_t>& offlineStreams,
+                                std::deque<std::shared_ptr<HalRequest>>& offlineReqs,
+                                const std::map<int, CirculatingBuffers>& circulatingBuffers,
+                                /*out*/ CameraOfflineSessionInfo* info);
+
+    // Protect (most of) HIDL interface methods from synchronized-entering
+    mutable Mutex mInterfaceLock;
+
+    mutable Mutex mLock;  // Protect all private members except otherwise noted
+    const std::shared_ptr<ICameraDeviceCallback> mCallback;
+    const ExternalCameraConfig& mCfg;
+    const common::V1_0::helper::CameraMetadata mCameraCharacteristics;
+    const std::vector<SupportedV4L2Format> mSupportedFormats;
+    const CroppingType mCroppingType;
+    const std::string mCameraId;
+
+    // Not protected by mLock, this is almost a const.
+    // Setup in constructor, reset in close() after OutputThread is joined
+    unique_fd mV4l2Fd;
+
+    // device is closed either
+    //    - closed by user
+    //    - init failed
+    //    - camera disconnected
+    bool mClosed = false;
+    bool mInitialized = false;
+    bool mInitFail = false;
+    bool mFirstRequest = false;
+    common::V1_0::helper::CameraMetadata mLatestReqSetting;
+
+    bool mV4l2Streaming = false;
+    SupportedV4L2Format mV4l2StreamingFmt;
+    double mV4l2StreamingFps = 0.0;
+    size_t mV4L2BufferCount = 0;
+
+    static const int kBufferWaitTimeoutSec = 3;  // TODO: handle long exposure (or not allowing)
+    std::mutex mV4l2BufferLock;                  // protect the buffer count and condition below
+    std::condition_variable mV4L2BufferReturned;
+    size_t mNumDequeuedV4l2Buffers = 0;
+    uint32_t mMaxV4L2BufferSize = 0;
+
+    // Not protected by mLock (but might be used when mLock is locked)
+    std::shared_ptr<OutputThread> mOutputThread;
+
+    // Stream ID -> Stream cache
+    std::unordered_map<int, Stream> mStreamMap;
+
+    std::mutex mInflightFramesLock;  // protect mInflightFrames
+    std::unordered_set<uint32_t> mInflightFrames;
+
+    // Stream ID -> circulating buffers map
+    std::map<int, CirculatingBuffers> mCirculatingBuffers;
+    // Protect mCirculatingBuffers, must not lock mLock after acquiring this lock
+    mutable Mutex mCbsLock;
+
+    std::mutex mAfTriggerLock;  // protect mAfTrigger
+    bool mAfTrigger = false;
+
+    uint32_t mBlobBufferSize = 0;
+
+    static HandleImporter sHandleImporter;
+
+    bool mSupportBufMgr;
+    std::shared_ptr<BufferRequestThread> mBufferRequestThread;
+
+    /* Beginning of members not changed after initialize() */
+    using RequestMetadataQueue = AidlMessageQueue<int8_t, SynchronizedReadWrite>;
+    std::unique_ptr<RequestMetadataQueue> mRequestMetadataQueue;
+    using ResultMetadataQueue = AidlMessageQueue<int8_t, SynchronizedReadWrite>;
+    std::shared_ptr<ResultMetadataQueue> mResultMetadataQueue;
+
+    // Protect against invokeProcessCaptureResultCallback()
+    Mutex mProcessCaptureResultLock;
+
+    // tracks last seen stream config counter
+    int32_t mLastStreamConfigCounter = -1;
+
+    std::unordered_map<RequestTemplate, CameraMetadata> mDefaultRequests;
+
+    const Size mMaxThumbResolution;
+    const Size mMaxJpegResolution;
+
+    std::string mExifMake;
+    std::string mExifModel;
+    /* End of members not changed after initialize() */
+};
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERADEVICESESSION_H_
diff --git a/camera/device/default/ExternalCameraOfflineSession.cpp b/camera/device/default/ExternalCameraOfflineSession.cpp
new file mode 100644
index 0000000..4c7f732
--- /dev/null
+++ b/camera/device/default/ExternalCameraOfflineSession.cpp
@@ -0,0 +1,547 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ExtCamOfflnSsn"
+#include <android/log.h>
+
+#include "ExternalCameraOfflineSession.h"
+
+#include <aidl/android/hardware/camera/device/BufferStatus.h>
+#include <aidl/android/hardware/camera/device/ErrorMsg.h>
+#include <aidl/android/hardware/camera/device/ShutterMsg.h>
+#include <aidl/android/hardware/camera/device/StreamBuffer.h>
+#include <aidlcommonsupport/NativeHandle.h>
+#include <convert.h>
+#include <linux/videodev2.h>
+#include <sync/sync.h>
+#include <utils/Trace.h>
+
+#define HAVE_JPEG  // required for libyuv.h to export MJPEG decode APIs
+#include <libyuv.h>
+
+namespace {
+
+// Size of request/result metadata fast message queue. Change to 0 to always use hwbinder buffer.
+constexpr size_t kMetadataMsgQueueSize = 1 << 18 /* 256kB */;
+
+}  // anonymous namespace
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::device::BufferStatus;
+using ::aidl::android::hardware::camera::device::ErrorMsg;
+using ::aidl::android::hardware::camera::device::ShutterMsg;
+using ::aidl::android::hardware::camera::device::StreamBuffer;
+
+// Static instance
+HandleImporter ExternalCameraOfflineSession::sHandleImporter;
+
+ExternalCameraOfflineSession::ExternalCameraOfflineSession(
+        const CroppingType& croppingType, const common::V1_0::helper::CameraMetadata& chars,
+        const std::string& cameraId, const std::string& exifMake, const std::string& exifModel,
+        uint32_t blobBufferSize, bool afTrigger, const std::vector<Stream>& offlineStreams,
+        std::deque<std::shared_ptr<HalRequest>>& offlineReqs,
+        const std::map<int, CirculatingBuffers>& circulatingBuffers)
+    : mCroppingType(croppingType),
+      mChars(chars),
+      mCameraId(cameraId),
+      mExifMake(exifMake),
+      mExifModel(exifModel),
+      mBlobBufferSize(blobBufferSize),
+      mAfTrigger(afTrigger),
+      mOfflineStreams(offlineStreams),
+      mOfflineReqs(offlineReqs),
+      mCirculatingBuffers(circulatingBuffers) {}
+
+ExternalCameraOfflineSession::~ExternalCameraOfflineSession() {
+    close();
+}
+
+bool ExternalCameraOfflineSession::initialize() {
+    mResultMetadataQueue =
+            std::make_shared<ResultMetadataQueue>(kMetadataMsgQueueSize, false /* non blocking */);
+    if (!mResultMetadataQueue->isValid()) {
+        ALOGE("%s: invalid result fmq", __FUNCTION__);
+        return true;
+    }
+    return false;
+}
+
+Status ExternalCameraOfflineSession::importBuffer(int32_t streamId, uint64_t bufId,
+                                                  buffer_handle_t buf,
+                                                  buffer_handle_t** outBufPtr) {
+    Mutex::Autolock _l(mCbsLock);
+    return importBufferImpl(mCirculatingBuffers, sHandleImporter, streamId, bufId, buf, outBufPtr);
+}
+
+Status ExternalCameraOfflineSession::processCaptureResult(std::shared_ptr<HalRequest>& req) {
+    ATRACE_CALL();
+    // Fill output buffers
+    std::vector<CaptureResult> results;
+    results.resize(1);
+    CaptureResult& result = results[0];
+    result.frameNumber = req->frameNumber;
+    result.partialResult = 1;
+    result.inputBuffer.streamId = -1;
+    result.outputBuffers.resize(req->buffers.size());
+    for (size_t i = 0; i < req->buffers.size(); i++) {
+        StreamBuffer& outputBuffer = result.outputBuffers[i];
+        outputBuffer.streamId = req->buffers[i].streamId;
+        outputBuffer.bufferId = req->buffers[i].bufferId;
+        if (req->buffers[i].fenceTimeout) {
+            outputBuffer.status = BufferStatus::ERROR;
+            if (req->buffers[i].acquireFence >= 0) {
+                native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+                handle->data[0] = req->buffers[i].acquireFence;
+                result.outputBuffers[i].releaseFence = android::makeToAidl(handle);
+            }
+            notifyError(req->frameNumber, req->buffers[i].streamId, ErrorCode::ERROR_BUFFER);
+        } else {
+            result.outputBuffers[i].status = BufferStatus::OK;
+            // TODO: refactor
+            if (req->buffers[i].acquireFence >= 0) {
+                native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+                handle->data[0] = req->buffers[i].acquireFence;
+                outputBuffer.releaseFence = android::makeToAidl(handle);
+            }
+        }
+    }
+
+    // Fill capture result metadata
+    fillCaptureResult(req->setting, req->shutterTs);
+    const camera_metadata_t* rawResult = req->setting.getAndLock();
+    convertToAidl(rawResult, &result.result);
+    req->setting.unlock(rawResult);
+
+    // Callback into framework
+    invokeProcessCaptureResultCallback(results, /* tryWriteFmq */ true);
+    freeReleaseFences(results);
+    return Status::OK;
+}
+
+#define UPDATE(md, tag, data, size)               \
+    do {                                          \
+        if ((md).update((tag), (data), (size))) { \
+            ALOGE("Update " #tag " failed!");     \
+            return BAD_VALUE;                     \
+        }                                         \
+    } while (0)
+
+status_t ExternalCameraOfflineSession::fillCaptureResult(common::V1_0::helper::CameraMetadata md,
+                                                         nsecs_t timestamp) {
+    bool afTrigger = false;
+    {
+        std::lock_guard<std::mutex> lk(mAfTriggerLock);
+        afTrigger = mAfTrigger;
+        if (md.exists(ANDROID_CONTROL_AF_TRIGGER)) {
+            camera_metadata_entry entry = md.find(ANDROID_CONTROL_AF_TRIGGER);
+            if (entry.data.u8[0] == ANDROID_CONTROL_AF_TRIGGER_START) {
+                mAfTrigger = afTrigger = true;
+            } else if (entry.data.u8[0] == ANDROID_CONTROL_AF_TRIGGER_CANCEL) {
+                mAfTrigger = afTrigger = false;
+            }
+        }
+    }
+
+    // For USB camera, the USB camera handles everything and we don't have control
+    // over AF. We only simply fake the AF metadata based on the request
+    // received here.
+    uint8_t afState;
+    if (afTrigger) {
+        afState = ANDROID_CONTROL_AF_STATE_FOCUSED_LOCKED;
+    } else {
+        afState = ANDROID_CONTROL_AF_STATE_INACTIVE;
+    }
+    UPDATE(md, ANDROID_CONTROL_AF_STATE, &afState, 1);
+
+    camera_metadata_ro_entry activeArraySize = mChars.find(ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE);
+
+    return fillCaptureResultCommon(md, timestamp, activeArraySize);
+}
+void ExternalCameraOfflineSession::invokeProcessCaptureResultCallback(
+        std::vector<CaptureResult>& results, bool tryWriteFmq) {
+    if (mProcessCaptureResultLock.tryLock() != OK) {
+        const nsecs_t NS_TO_SECOND = 1E9;
+        ALOGV("%s: previous call is not finished! waiting 1s...", __FUNCTION__);
+        if (mProcessCaptureResultLock.timedLock(/* 1s */ NS_TO_SECOND) != OK) {
+            ALOGE("%s: cannot acquire lock in 1s, cannot proceed", __FUNCTION__);
+            return;
+        }
+    }
+    if (tryWriteFmq && mResultMetadataQueue->availableToWrite() > 0) {
+        for (CaptureResult& result : results) {
+            if (!result.result.metadata.empty()) {
+                if (mResultMetadataQueue->write(
+                            reinterpret_cast<int8_t*>(result.result.metadata.data()),
+                            result.result.metadata.size())) {
+                    result.fmqResultSize = result.result.metadata.size();
+                    result.result.metadata.clear();
+                } else {
+                    ALOGW("%s: couldn't utilize fmq, fall back to hwbinder", __FUNCTION__);
+                    result.fmqResultSize = 0;
+                }
+            } else {
+                result.fmqResultSize = 0;
+            }
+        }
+    }
+    auto status = mCallback->processCaptureResult(results);
+    if (!status.isOk()) {
+        ALOGE("%s: processCaptureResult ERROR : %d:%d", __FUNCTION__, status.getExceptionCode(),
+              status.getServiceSpecificError());
+    }
+
+    mProcessCaptureResultLock.unlock();
+}
+
+Status ExternalCameraOfflineSession::processCaptureRequestError(
+        const std::shared_ptr<HalRequest>& req, std::vector<NotifyMsg>* outMsgs,
+        std::vector<CaptureResult>* outResults) {
+    ATRACE_CALL();
+
+    if (outMsgs == nullptr) {
+        notifyError(/*frameNum*/ req->frameNumber, /*stream*/ -1, ErrorCode::ERROR_REQUEST);
+    } else {
+        NotifyMsg shutter;
+        shutter.set<NotifyMsg::Tag::shutter>(ShutterMsg{
+                .frameNumber = req->frameNumber,
+                .timestamp = req->shutterTs,
+        });
+
+        NotifyMsg error;
+        error.set<NotifyMsg::Tag::error>(ErrorMsg{.frameNumber = req->frameNumber,
+                                                  .errorStreamId = -1,
+                                                  .errorCode = ErrorCode::ERROR_REQUEST});
+        outMsgs->push_back(shutter);
+        outMsgs->push_back(error);
+    }
+
+    // Fill output buffers
+    CaptureResult result;
+    result.frameNumber = req->frameNumber;
+    result.partialResult = 1;
+    result.inputBuffer.streamId = -1;
+    result.outputBuffers.resize(req->buffers.size());
+    for (size_t i = 0; i < req->buffers.size(); i++) {
+        StreamBuffer& outputBuffer = result.outputBuffers[i];
+        outputBuffer.streamId = req->buffers[i].streamId;
+        outputBuffer.bufferId = req->buffers[i].bufferId;
+        outputBuffer.status = BufferStatus::ERROR;
+        if (req->buffers[i].acquireFence >= 0) {
+            native_handle_t* handle = native_handle_create(/*numFds*/ 1, /*numInts*/ 0);
+            handle->data[0] = req->buffers[i].acquireFence;
+            outputBuffer.releaseFence = makeToAidl(handle);
+        }
+    }
+
+    if (outResults == nullptr) {
+        // Callback into framework
+        std::vector<CaptureResult> results(1);
+        results[0] = std::move(result);
+        invokeProcessCaptureResultCallback(results, /* tryWriteFmq */ true);
+        freeReleaseFences(results);
+    } else {
+        outResults->push_back(std::move(result));
+    }
+    return Status::OK;
+}
+
+ssize_t ExternalCameraOfflineSession::getJpegBufferSize(int32_t, int32_t) const {
+    // Empty implementation here as the jpeg buffer size is passed in by ctor
+    return 0;
+}
+
+void ExternalCameraOfflineSession::notifyError(int32_t frameNumber, int32_t streamId,
+                                               ErrorCode ec) {
+    NotifyMsg msg;
+    msg.set<NotifyMsg::Tag::error>(
+            ErrorMsg{.frameNumber = frameNumber, .errorStreamId = streamId, .errorCode = ec});
+    mCallback->notify({msg});
+}
+
+ScopedAStatus ExternalCameraOfflineSession::setCallback(
+        const std::shared_ptr<ICameraDeviceCallback>& in_cb) {
+    Mutex::Autolock _il(mInterfaceLock);
+    if (mCallback != nullptr && in_cb != nullptr) {
+        ALOGE("%s: callback must not be set twice!", __FUNCTION__);
+        return fromStatus(Status::OK);
+    }
+    mCallback = in_cb;
+
+    initOutputThread();
+
+    if (mOutputThread == nullptr) {
+        ALOGE("%s: init OutputThread failed!", __FUNCTION__);
+    }
+    return fromStatus(Status::OK);
+}
+void ExternalCameraOfflineSession::initOutputThread() {
+    if (mOutputThread != nullptr) {
+        ALOGE("%s: OutputThread already exist!", __FUNCTION__);
+        return;
+    }
+
+    // Grab a shared_ptr to 'this' from ndk::SharedRefBase::ref()
+    std::shared_ptr<ExternalCameraOfflineSession> thiz = ref<ExternalCameraOfflineSession>();
+
+    mBufferRequestThread = std::make_shared<ExternalCameraDeviceSession::BufferRequestThread>(
+            /*parent=*/thiz, mCallback);
+    mBufferRequestThread->run();
+
+    mOutputThread = std::make_shared<OutputThread>(/*parent=*/thiz, mCroppingType, mChars,
+                                                   mBufferRequestThread, mOfflineReqs);
+
+    mOutputThread->setExifMakeModel(mExifMake, mExifModel);
+
+    Size inputSize = {mOfflineReqs[0]->frameIn->mWidth, mOfflineReqs[0]->frameIn->mHeight};
+    Size maxThumbSize = getMaxThumbnailResolution(mChars);
+    mOutputThread->allocateIntermediateBuffers(inputSize, maxThumbSize, mOfflineStreams,
+                                               mBlobBufferSize);
+
+    mOutputThread->run();
+}
+
+ScopedAStatus ExternalCameraOfflineSession::getCaptureResultMetadataQueue(
+        MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) {
+    Mutex::Autolock _il(mInterfaceLock);
+    *_aidl_return = mResultMetadataQueue->dupeDesc();
+    return fromStatus(Status::OK);
+}
+
+ScopedAStatus ExternalCameraOfflineSession::close() {
+    Mutex::Autolock _il(mInterfaceLock);
+    {
+        Mutex::Autolock _l(mLock);
+        if (mClosed) {
+            ALOGW("%s: offline session already closed!", __FUNCTION__);
+            return fromStatus(Status::OK);
+        }
+    }
+    if (mBufferRequestThread != nullptr) {
+        mBufferRequestThread->requestExitAndWait();
+        mBufferRequestThread.reset();
+    }
+    if (mOutputThread) {
+        mOutputThread->flush();
+        mOutputThread->requestExitAndWait();
+        mOutputThread.reset();
+    }
+
+    Mutex::Autolock _l(mLock);
+    // free all buffers
+    {
+        Mutex::Autolock _cbl(mCbsLock);
+        for (auto& stream : mOfflineStreams) {
+            cleanupBuffersLocked(stream.id);
+        }
+    }
+    mCallback.reset();
+    mClosed = true;
+    return fromStatus(Status::OK);
+}
+void ExternalCameraOfflineSession::cleanupBuffersLocked(int32_t id) {
+    for (auto& pair : mCirculatingBuffers.at(id)) {
+        sHandleImporter.freeBuffer(pair.second);
+    }
+    mCirculatingBuffers[id].clear();
+    mCirculatingBuffers.erase(id);
+}
+
+bool ExternalCameraOfflineSession::OutputThread::threadLoop() {
+    auto parent = mParent.lock();
+    if (parent == nullptr) {
+        ALOGE("%s: session has been disconnected!", __FUNCTION__);
+        return false;
+    }
+
+    if (mOfflineReqs.empty()) {
+        ALOGI("%s: all offline requests are processed. Stopping.", __FUNCTION__);
+        return false;
+    }
+
+    std::shared_ptr<HalRequest> req = mOfflineReqs.front();
+    mOfflineReqs.pop_front();
+
+    auto onDeviceError = [&](auto... args) {
+        ALOGE(args...);
+        parent->notifyError(req->frameNumber, /*stream*/ -1, ErrorCode::ERROR_DEVICE);
+        signalRequestDone();
+        return false;
+    };
+
+    if (req->frameIn->mFourcc != V4L2_PIX_FMT_MJPEG && req->frameIn->mFourcc != V4L2_PIX_FMT_Z16) {
+        return onDeviceError("%s: do not support V4L2 format %c%c%c%c", __FUNCTION__,
+                             req->frameIn->mFourcc & 0xFF, (req->frameIn->mFourcc >> 8) & 0xFF,
+                             (req->frameIn->mFourcc >> 16) & 0xFF,
+                             (req->frameIn->mFourcc >> 24) & 0xFF);
+    }
+
+    int res = requestBufferStart(req->buffers);
+    if (res != 0) {
+        ALOGE("%s: send BufferRequest failed! res %d", __FUNCTION__, res);
+        return onDeviceError("%s: failed to send buffer request!", __FUNCTION__);
+    }
+
+    std::unique_lock<std::mutex> lk(mBufferLock);
+    // Convert input V4L2 frame to YU12 of the same size
+    // TODO: see if we can save some computation by converting to YV12 here
+    uint8_t* inData;
+    size_t inDataSize;
+    if (req->frameIn->getData(&inData, &inDataSize) != 0) {
+        lk.unlock();
+        return onDeviceError("%s: V4L2 buffer map failed", __FUNCTION__);
+    }
+
+    // TODO: in some special case maybe we can decode jpg directly to gralloc output?
+    if (req->frameIn->mFourcc == V4L2_PIX_FMT_MJPEG) {
+        ATRACE_BEGIN("MJPGtoI420");
+        int convRes = libyuv::MJPGToI420(
+                inData, inDataSize, static_cast<uint8_t*>(mYu12FrameLayout.y),
+                mYu12FrameLayout.yStride, static_cast<uint8_t*>(mYu12FrameLayout.cb),
+                mYu12FrameLayout.cStride, static_cast<uint8_t*>(mYu12FrameLayout.cr),
+                mYu12FrameLayout.cStride, mYu12Frame->mWidth, mYu12Frame->mHeight,
+                mYu12Frame->mWidth, mYu12Frame->mHeight);
+        ATRACE_END();
+
+        if (convRes != 0) {
+            // For some webcam, the first few V4L2 frames might be malformed...
+            ALOGE("%s: Convert V4L2 frame to YU12 failed! res %d", __FUNCTION__, convRes);
+            lk.unlock();
+            Status st = parent->processCaptureRequestError(req);
+            if (st != Status::OK) {
+                return onDeviceError("%s: failed to process capture request error!", __FUNCTION__);
+            }
+            signalRequestDone();
+            return true;
+        }
+    }
+
+    ATRACE_BEGIN("Wait for BufferRequest done");
+    res = waitForBufferRequestDone(&req->buffers);
+    ATRACE_END();
+
+    if (res != 0) {
+        ALOGE("%s: wait for BufferRequest done failed! res %d", __FUNCTION__, res);
+        lk.unlock();
+        return onDeviceError("%s: failed to process buffer request error!", __FUNCTION__);
+    }
+
+    ALOGV("%s processing new request", __FUNCTION__);
+    const int kSyncWaitTimeoutMs = 500;
+    for (auto& halBuf : req->buffers) {
+        if (*(halBuf.bufPtr) == nullptr) {
+            ALOGW("%s: buffer for stream %d missing", __FUNCTION__, halBuf.streamId);
+            halBuf.fenceTimeout = true;
+        } else if (halBuf.acquireFence >= 0) {
+            int ret = sync_wait(halBuf.acquireFence, kSyncWaitTimeoutMs);
+            if (ret) {
+                halBuf.fenceTimeout = true;
+            } else {
+                ::close(halBuf.acquireFence);
+                halBuf.acquireFence = -1;
+            }
+        }
+
+        if (halBuf.fenceTimeout) {
+            continue;
+        }
+
+        // Gralloc lockYCbCr the buffer
+        switch (halBuf.format) {
+            case PixelFormat::BLOB: {
+                int ret = createJpegLocked(halBuf, req->setting);
+
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: createJpegLocked failed with %d", __FUNCTION__, ret);
+                }
+            } break;
+            case PixelFormat::Y16: {
+                void* outLayout = sHandleImporter.lock(
+                        *(halBuf.bufPtr), static_cast<uint64_t>(halBuf.usage), inDataSize);
+
+                std::memcpy(outLayout, inData, inDataSize);
+
+                int relFence = sHandleImporter.unlock(*(halBuf.bufPtr));
+                if (relFence >= 0) {
+                    halBuf.acquireFence = relFence;
+                }
+            } break;
+            case PixelFormat::YCBCR_420_888:
+            case PixelFormat::YV12: {
+                IMapper::Rect outRect{0, 0, static_cast<int32_t>(halBuf.width),
+                                      static_cast<int32_t>(halBuf.height)};
+                YCbCrLayout outLayout = sHandleImporter.lockYCbCr(
+                        *(halBuf.bufPtr), static_cast<uint64_t>(halBuf.usage), outRect);
+                ALOGV("%s: outLayout y %p cb %p cr %p y_str %d c_str %d c_step %d", __FUNCTION__,
+                      outLayout.y, outLayout.cb, outLayout.cr, outLayout.yStride, outLayout.cStride,
+                      outLayout.chromaStep);
+
+                // Convert to output buffer size/format
+                uint32_t outputFourcc = getFourCcFromLayout(outLayout);
+                ALOGV("%s: converting to format %c%c%c%c", __FUNCTION__, outputFourcc & 0xFF,
+                      (outputFourcc >> 8) & 0xFF, (outputFourcc >> 16) & 0xFF,
+                      (outputFourcc >> 24) & 0xFF);
+
+                YCbCrLayout cropAndScaled;
+                ATRACE_BEGIN("cropAndScaleLocked");
+                int ret = cropAndScaleLocked(mYu12Frame, Size{halBuf.width, halBuf.height},
+                                             &cropAndScaled);
+                ATRACE_END();
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: crop and scale failed!", __FUNCTION__);
+                }
+
+                Size sz{halBuf.width, halBuf.height};
+                ATRACE_BEGIN("formatConvert");
+                ret = formatConvert(cropAndScaled, outLayout, sz, outputFourcc);
+                ATRACE_END();
+                if (ret != 0) {
+                    lk.unlock();
+                    return onDeviceError("%s: format coversion failed!", __FUNCTION__);
+                }
+                int relFence = sHandleImporter.unlock(*(halBuf.bufPtr));
+                if (relFence >= 0) {
+                    halBuf.acquireFence = relFence;
+                }
+            } break;
+            default:
+                lk.unlock();
+                return onDeviceError("%s: unknown output format %x", __FUNCTION__, halBuf.format);
+        }
+    }  // for each buffer
+    mScaledYu12Frames.clear();
+
+    // Don't hold the lock while calling back to parent
+    lk.unlock();
+    Status st = parent->processCaptureResult(req);
+    if (st != Status::OK) {
+        return onDeviceError("%s: failed to process capture result!", __FUNCTION__);
+    }
+    signalRequestDone();
+    return true;
+}
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/camera/device/default/ExternalCameraOfflineSession.h b/camera/device/default/ExternalCameraOfflineSession.h
new file mode 100644
index 0000000..5795c95
--- /dev/null
+++ b/camera/device/default/ExternalCameraOfflineSession.h
@@ -0,0 +1,143 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAOFFLINESESSION_H_
+#define HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAOFFLINESESSION_H_
+
+#include <ExternalCameraDeviceSession.h>
+#include <ExternalCameraUtils.h>
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <aidl/android/hardware/camera/device/BnCameraOfflineSession.h>
+#include <aidl/android/hardware/camera/device/Stream.h>
+#include <fmq/AidlMessageQueue.h>
+#include <utils/RefBase.h>
+#include <deque>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::Status;
+using ::aidl::android::hardware::camera::device::BnCameraOfflineSession;
+using ::aidl::android::hardware::camera::device::ICameraDeviceCallback;
+using ::aidl::android::hardware::camera::device::Stream;
+using ::aidl::android::hardware::common::fmq::MQDescriptor;
+using ::aidl::android::hardware::common::fmq::SynchronizedReadWrite;
+
+class ExternalCameraOfflineSession : public BnCameraOfflineSession,
+                                     public virtual RefBase,
+                                     public virtual OutputThreadInterface {
+  public:
+    ExternalCameraOfflineSession(const CroppingType& croppingType,
+                                 const common::V1_0::helper::CameraMetadata& chars,
+                                 const std::string& cameraId, const std::string& exifMake,
+                                 const std::string& exifModel, uint32_t blobBufferSize,
+                                 bool afTrigger, const std::vector<Stream>& offlineStreams,
+                                 std::deque<std::shared_ptr<HalRequest>>& offlineReqs,
+                                 const std::map<int, CirculatingBuffers>& circulatingBuffers);
+
+    ~ExternalCameraOfflineSession() override;
+
+    bool initialize();
+
+    // Methods from OutputThreadInterface
+    Status importBuffer(int32_t streamId, uint64_t bufId, buffer_handle_t buf,
+                        /*out*/ buffer_handle_t** outBufPtr) override;
+
+    Status processCaptureResult(std::shared_ptr<HalRequest>&) override;
+
+    Status processCaptureRequestError(const std::shared_ptr<HalRequest>&,
+                                      /*out*/ std::vector<NotifyMsg>* msgs,
+                                      /*out*/ std::vector<CaptureResult>* results) override;
+
+    ssize_t getJpegBufferSize(int32_t width, int32_t height) const override;
+
+    void notifyError(int32_t frameNumber, int32_t streamId, ErrorCode ec) override;
+    // End of OutputThreadInterface methods
+
+    ScopedAStatus setCallback(const std::shared_ptr<ICameraDeviceCallback>& in_cb) override;
+    ScopedAStatus getCaptureResultMetadataQueue(
+            MQDescriptor<int8_t, SynchronizedReadWrite>* _aidl_return) override;
+    ScopedAStatus close() override;
+
+  private:
+    class OutputThread : public ExternalCameraDeviceSession::OutputThread {
+      public:
+        OutputThread(std::weak_ptr<OutputThreadInterface> parent, CroppingType ct,
+                     const common::V1_0::helper::CameraMetadata& chars,
+                     std::shared_ptr<ExternalCameraDeviceSession::BufferRequestThread> bufReqThread,
+                     std::deque<std::shared_ptr<HalRequest>>& offlineReqs)
+            : ExternalCameraDeviceSession::OutputThread(std::move(parent), ct, chars,
+                                                        std::move(bufReqThread)),
+              mOfflineReqs(offlineReqs) {}
+
+        bool threadLoop() override;
+
+      protected:
+        std::deque<std::shared_ptr<HalRequest>> mOfflineReqs;
+    };  // OutputThread
+
+    status_t fillCaptureResult(common::V1_0::helper::CameraMetadata md, nsecs_t timestamp);
+    void invokeProcessCaptureResultCallback(std::vector<CaptureResult>& results, bool tryWriteFmq);
+    void initOutputThread();
+    void cleanupBuffersLocked(int32_t id);
+
+    // Protect (most of) HIDL interface methods from synchronized-entering
+    mutable Mutex mInterfaceLock;
+
+    mutable Mutex mLock;  // Protect all data members except otherwise noted
+
+    bool mClosed = false;
+    const CroppingType mCroppingType;
+    const common::V1_0::helper::CameraMetadata mChars;
+    const std::string mCameraId;
+    const std::string mExifMake;
+    const std::string mExifModel;
+    const uint32_t mBlobBufferSize;
+
+    std::mutex mAfTriggerLock;  // protect mAfTrigger
+    bool mAfTrigger;
+
+    const std::vector<Stream> mOfflineStreams;
+    std::deque<std::shared_ptr<HalRequest>> mOfflineReqs;
+
+    // Protect mCirculatingBuffers, must not lock mLock after acquiring this lock
+    mutable Mutex mCbsLock;
+    std::map<int, CirculatingBuffers> mCirculatingBuffers;
+
+    static HandleImporter sHandleImporter;
+
+    using ResultMetadataQueue = AidlMessageQueue<int8_t, SynchronizedReadWrite>;
+    std::shared_ptr<ResultMetadataQueue> mResultMetadataQueue;
+
+    // Protect against invokeProcessCaptureResultCallback()
+    Mutex mProcessCaptureResultLock;
+
+    std::shared_ptr<ICameraDeviceCallback> mCallback;
+
+    std::shared_ptr<ExternalCameraDeviceSession::BufferRequestThread> mBufferRequestThread;
+    std::shared_ptr<OutputThread> mOutputThread;
+};
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAOFFLINESESSION_H_
diff --git a/camera/device/default/ExternalCameraUtils.cpp b/camera/device/default/ExternalCameraUtils.cpp
new file mode 100644
index 0000000..cfb95f2
--- /dev/null
+++ b/camera/device/default/ExternalCameraUtils.cpp
@@ -0,0 +1,860 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ExtCamUtils"
+// #define LOG_NDEBUG 0
+
+#include "ExternalCameraUtils.h"
+
+#include <aidlcommonsupport/NativeHandle.h>
+#include <jpeglib.h>
+#include <linux/videodev2.h>
+#include <log/log.h>
+#include <algorithm>
+#include <cinttypes>
+#include <cmath>
+
+#define HAVE_JPEG  // required for libyuv.h to export MJPEG decode APIs
+#include <libyuv.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+
+namespace external {
+namespace common {
+
+namespace {
+const int kDefaultCameraIdOffset = 100;
+const int kDefaultJpegBufSize = 5 << 20;  // 5MB
+const int kDefaultNumVideoBuffer = 4;
+const int kDefaultNumStillBuffer = 2;
+const int kDefaultOrientation = 0;  // suitable for natural landscape displays like tablet/TV
+                                    // For phone devices 270 is better
+}  // anonymous namespace
+
+const char* ExternalCameraConfig::kDefaultCfgPath = "/vendor/etc/external_camera_config.xml";
+
+ExternalCameraConfig ExternalCameraConfig::loadFromCfg(const char* cfgPath) {
+    using namespace tinyxml2;
+    ExternalCameraConfig ret;
+
+    XMLDocument configXml;
+    XMLError err = configXml.LoadFile(cfgPath);
+    if (err != XML_SUCCESS) {
+        ALOGE("%s: Unable to load external camera config file '%s'. Error: %s", __FUNCTION__,
+              cfgPath, XMLDocument::ErrorIDToName(err));
+        return ret;
+    } else {
+        ALOGI("%s: load external camera config succeeded!", __FUNCTION__);
+    }
+
+    XMLElement* extCam = configXml.FirstChildElement("ExternalCamera");
+    if (extCam == nullptr) {
+        ALOGI("%s: no external camera config specified", __FUNCTION__);
+        return ret;
+    }
+
+    XMLElement* providerCfg = extCam->FirstChildElement("Provider");
+    if (providerCfg == nullptr) {
+        ALOGI("%s: no external camera provider config specified", __FUNCTION__);
+        return ret;
+    }
+
+    XMLElement* cameraIdOffset = providerCfg->FirstChildElement("CameraIdOffset");
+    if (cameraIdOffset != nullptr) {
+        ret.cameraIdOffset = std::atoi(cameraIdOffset->GetText());
+    }
+
+    XMLElement* ignore = providerCfg->FirstChildElement("ignore");
+    if (ignore == nullptr) {
+        ALOGI("%s: no internal ignored device specified", __FUNCTION__);
+        return ret;
+    }
+
+    XMLElement* id = ignore->FirstChildElement("id");
+    while (id != nullptr) {
+        const char* text = id->GetText();
+        if (text != nullptr) {
+            ret.mInternalDevices.insert(text);
+            ALOGI("%s: device %s will be ignored by external camera provider", __FUNCTION__, text);
+        }
+        id = id->NextSiblingElement("id");
+    }
+
+    XMLElement* deviceCfg = extCam->FirstChildElement("Device");
+    if (deviceCfg == nullptr) {
+        ALOGI("%s: no external camera device config specified", __FUNCTION__);
+        return ret;
+    }
+
+    XMLElement* jpegBufSz = deviceCfg->FirstChildElement("MaxJpegBufferSize");
+    if (jpegBufSz == nullptr) {
+        ALOGI("%s: no max jpeg buffer size specified", __FUNCTION__);
+    } else {
+        ret.maxJpegBufSize = jpegBufSz->UnsignedAttribute("bytes", /*Default*/ kDefaultJpegBufSize);
+    }
+
+    XMLElement* numVideoBuf = deviceCfg->FirstChildElement("NumVideoBuffers");
+    if (numVideoBuf == nullptr) {
+        ALOGI("%s: no num video buffers specified", __FUNCTION__);
+    } else {
+        ret.numVideoBuffers =
+                numVideoBuf->UnsignedAttribute("count", /*Default*/ kDefaultNumVideoBuffer);
+    }
+
+    XMLElement* numStillBuf = deviceCfg->FirstChildElement("NumStillBuffers");
+    if (numStillBuf == nullptr) {
+        ALOGI("%s: no num still buffers specified", __FUNCTION__);
+    } else {
+        ret.numStillBuffers =
+                numStillBuf->UnsignedAttribute("count", /*Default*/ kDefaultNumStillBuffer);
+    }
+
+    XMLElement* fpsList = deviceCfg->FirstChildElement("FpsList");
+    if (fpsList == nullptr) {
+        ALOGI("%s: no fps list specified", __FUNCTION__);
+    } else {
+        if (!updateFpsList(fpsList, ret.fpsLimits)) {
+            return ret;
+        }
+    }
+
+    XMLElement* depth = deviceCfg->FirstChildElement("Depth16Supported");
+    if (depth == nullptr) {
+        ret.depthEnabled = false;
+        ALOGI("%s: depth output is not enabled", __FUNCTION__);
+    } else {
+        ret.depthEnabled = depth->BoolAttribute("enabled", false);
+    }
+
+    if (ret.depthEnabled) {
+        XMLElement* depthFpsList = deviceCfg->FirstChildElement("DepthFpsList");
+        if (depthFpsList == nullptr) {
+            ALOGW("%s: no depth fps list specified", __FUNCTION__);
+        } else {
+            if (!updateFpsList(depthFpsList, ret.depthFpsLimits)) {
+                return ret;
+            }
+        }
+    }
+
+    XMLElement* minStreamSize = deviceCfg->FirstChildElement("MinimumStreamSize");
+    if (minStreamSize == nullptr) {
+        ALOGI("%s: no minimum stream size specified", __FUNCTION__);
+    } else {
+        ret.minStreamSize = {
+                static_cast<int32_t>(minStreamSize->UnsignedAttribute("width", /*Default*/ 0)),
+                static_cast<int32_t>(minStreamSize->UnsignedAttribute("height", /*Default*/ 0))};
+    }
+
+    XMLElement* orientation = deviceCfg->FirstChildElement("Orientation");
+    if (orientation == nullptr) {
+        ALOGI("%s: no sensor orientation specified", __FUNCTION__);
+    } else {
+        ret.orientation = orientation->IntAttribute("degree", /*Default*/ kDefaultOrientation);
+    }
+
+    ALOGI("%s: external camera cfg loaded: maxJpgBufSize %d,"
+          " num video buffers %d, num still buffers %d, orientation %d",
+          __FUNCTION__, ret.maxJpegBufSize, ret.numVideoBuffers, ret.numStillBuffers,
+          ret.orientation);
+    for (const auto& limit : ret.fpsLimits) {
+        ALOGI("%s: fpsLimitList: %dx%d@%f", __FUNCTION__, limit.size.width, limit.size.height,
+              limit.fpsUpperBound);
+    }
+    for (const auto& limit : ret.depthFpsLimits) {
+        ALOGI("%s: depthFpsLimitList: %dx%d@%f", __FUNCTION__, limit.size.width, limit.size.height,
+              limit.fpsUpperBound);
+    }
+    ALOGI("%s: minStreamSize: %dx%d", __FUNCTION__, ret.minStreamSize.width,
+          ret.minStreamSize.height);
+    return ret;
+}
+
+bool ExternalCameraConfig::updateFpsList(tinyxml2::XMLElement* fpsList,
+                                         std::vector<FpsLimitation>& fpsLimits) {
+    using namespace tinyxml2;
+    std::vector<FpsLimitation> limits;
+    XMLElement* row = fpsList->FirstChildElement("Limit");
+    while (row != nullptr) {
+        FpsLimitation prevLimit{{0, 0}, 1000.0};
+        FpsLimitation limit = {
+                {/* width */ static_cast<int32_t>(row->UnsignedAttribute("width", /*Default*/ 0)),
+                 /* height */ static_cast<int32_t>(
+                         row->UnsignedAttribute("height", /*Default*/ 0))},
+                /* fpsUpperBound */ row->DoubleAttribute("fpsBound", /*Default*/ 1000.0)};
+        if (limit.size.width <= prevLimit.size.width ||
+            limit.size.height <= prevLimit.size.height ||
+            limit.fpsUpperBound >= prevLimit.fpsUpperBound) {
+            ALOGE("%s: FPS limit list must have increasing size and decreasing fps!"
+                  " Prev %dx%d@%f, Current %dx%d@%f",
+                  __FUNCTION__, prevLimit.size.width, prevLimit.size.height,
+                  prevLimit.fpsUpperBound, limit.size.width, limit.size.height,
+                  limit.fpsUpperBound);
+            return false;
+        }
+        limits.push_back(limit);
+        row = row->NextSiblingElement("Limit");
+    }
+    fpsLimits = limits;
+    return true;
+}
+
+ExternalCameraConfig::ExternalCameraConfig()
+    : cameraIdOffset(kDefaultCameraIdOffset),
+      maxJpegBufSize(kDefaultJpegBufSize),
+      numVideoBuffers(kDefaultNumVideoBuffer),
+      numStillBuffers(kDefaultNumStillBuffer),
+      depthEnabled(false),
+      orientation(kDefaultOrientation) {
+    fpsLimits.push_back({/* size */ {/* width */ 640, /* height */ 480}, /* fpsUpperBound */ 30.0});
+    fpsLimits.push_back({/* size */ {/* width */ 1280, /* height */ 720}, /* fpsUpperBound */ 7.5});
+    fpsLimits.push_back(
+            {/* size */ {/* width */ 1920, /* height */ 1080}, /* fpsUpperBound */ 5.0});
+    minStreamSize = {0, 0};
+}
+
+}  // namespace common
+}  // namespace external
+
+namespace device {
+namespace implementation {
+
+double SupportedV4L2Format::FrameRate::getFramesPerSecond() const {
+    return static_cast<double>(durationDenominator) / durationNumerator;
+}
+
+Frame::Frame(uint32_t width, uint32_t height, uint32_t fourcc)
+    : mWidth(width), mHeight(height), mFourcc(fourcc) {}
+Frame::~Frame() {}
+
+V4L2Frame::V4L2Frame(uint32_t w, uint32_t h, uint32_t fourcc, int bufIdx, int fd, uint32_t dataSize,
+                     uint64_t offset)
+    : Frame(w, h, fourcc), mBufferIndex(bufIdx), mFd(fd), mDataSize(dataSize), mOffset(offset) {}
+
+V4L2Frame::~V4L2Frame() {
+    unmap();
+}
+
+int V4L2Frame::getData(uint8_t** outData, size_t* dataSize) {
+    return map(outData, dataSize);
+}
+
+int V4L2Frame::map(uint8_t** data, size_t* dataSize) {
+    if (data == nullptr || dataSize == nullptr) {
+        ALOGI("%s: V4L2 buffer map bad argument: data %p, dataSize %p", __FUNCTION__, data,
+              dataSize);
+        return -EINVAL;
+    }
+
+    std::lock_guard<std::mutex> lk(mLock);
+    if (!mMapped) {
+        void* addr = mmap(nullptr, mDataSize, PROT_READ, MAP_SHARED, mFd, mOffset);
+        if (addr == MAP_FAILED) {
+            ALOGE("%s: V4L2 buffer map failed: %s", __FUNCTION__, strerror(errno));
+            return -EINVAL;
+        }
+        mData = static_cast<uint8_t*>(addr);
+        mMapped = true;
+    }
+    *data = mData;
+    *dataSize = mDataSize;
+    ALOGV("%s: V4L map FD %d, data %p size %zu", __FUNCTION__, mFd, mData, mDataSize);
+    return 0;
+}
+
+int V4L2Frame::unmap() {
+    std::lock_guard<std::mutex> lk(mLock);
+    if (mMapped) {
+        ALOGV("%s: V4L unmap data %p size %zu", __FUNCTION__, mData, mDataSize);
+        if (munmap(mData, mDataSize) != 0) {
+            ALOGE("%s: V4L2 buffer unmap failed: %s", __FUNCTION__, strerror(errno));
+            return -EINVAL;
+        }
+        mMapped = false;
+    }
+    return 0;
+}
+
+AllocatedFrame::AllocatedFrame(uint32_t w, uint32_t h) : Frame(w, h, V4L2_PIX_FMT_YUV420) {}
+AllocatedFrame::~AllocatedFrame() {}
+
+int AllocatedFrame::getData(uint8_t** outData, size_t* dataSize) {
+    YCbCrLayout layout;
+    int ret = allocate(&layout);
+    if (ret != 0) {
+        return ret;
+    }
+    *outData = mData.data();
+    *dataSize = mBufferSize;
+    return 0;
+}
+
+int AllocatedFrame::allocate(YCbCrLayout* out) {
+    std::lock_guard<std::mutex> lk(mLock);
+    if ((mWidth % 2) || (mHeight % 2)) {
+        ALOGE("%s: bad dimension %dx%d (not multiple of 2)", __FUNCTION__, mWidth, mHeight);
+        return -EINVAL;
+    }
+
+    // This frame might be sent to jpeglib to be encoded. Since AllocatedFrame only contains YUV420,
+    // jpeglib expects height and width of Y component to be an integral multiple of 2*DCTSIZE,
+    // and heights and widths of Cb and Cr components to be an integral multiple of DCTSIZE. If the
+    // image size does not meet this requirement, libjpeg expects its input to be padded to meet the
+    // constraints. This padding is removed from the final encoded image so the content in the
+    // padding doesn't matter. What matters is that the memory is accessible to jpeglib at the time
+    // of encoding.
+    // For example, if the image size is 1500x844 and DCTSIZE is 8, jpeglib expects a YUV 420
+    // frame with components of following sizes:
+    //   Y:      1504x848 because 1504 and 848 are the next smallest multiples of 2*8
+    //   Cb/Cr:  752x424 which are the next smallest multiples of 8
+
+    // jpeglib takes an array of row pointers which makes vertical padding trivial when setting up
+    // the pointers. Padding horizontally is a bit more complicated. AllocatedFrame holds the data
+    // in a flattened buffer, which means memory accesses past a row will flow into the next logical
+    // row. For any row of a component, we can consider the first few bytes of the next row as
+    // padding for the current one. This is true for Y and Cb components and all but last row of the
+    // Cr component. Reading past the last row of Cr component will lead to undefined behavior as
+    // libjpeg attempts to read memory past the allocated buffer. To prevent undefined behavior,
+    // the buffer allocated here is padded such that libjpeg never accesses unallocated memory when
+    // reading the last row. Effectively, we only need to ensure that the last row of Cr component
+    // has width that is an integral multiple of DCTSIZE.
+
+    size_t dataSize = mWidth * mHeight * 3 / 2;  // YUV420
+
+    size_t cbWidth = mWidth / 2;
+    size_t requiredCbWidth = DCTSIZE * ((cbWidth + DCTSIZE - 1) / DCTSIZE);
+    size_t padding = requiredCbWidth - cbWidth;
+    size_t finalSize = dataSize + padding;
+
+    if (mData.size() != finalSize) {
+        mData.resize(finalSize);
+        mBufferSize = dataSize;
+    }
+
+    if (out != nullptr) {
+        out->y = mData.data();
+        out->yStride = mWidth;
+        uint8_t* cbStart = mData.data() + mWidth * mHeight;
+        uint8_t* crStart = cbStart + mWidth * mHeight / 4;
+        out->cb = cbStart;
+        out->cr = crStart;
+        out->cStride = mWidth / 2;
+        out->chromaStep = 1;
+    }
+    return 0;
+}
+
+int AllocatedFrame::getLayout(YCbCrLayout* out) {
+    IMapper::Rect noCrop = {0, 0, static_cast<int32_t>(mWidth), static_cast<int32_t>(mHeight)};
+    return getCroppedLayout(noCrop, out);
+}
+
+int AllocatedFrame::getCroppedLayout(const IMapper::Rect& rect, YCbCrLayout* out) {
+    if (out == nullptr) {
+        ALOGE("%s: null out", __FUNCTION__);
+        return -1;
+    }
+
+    std::lock_guard<std::mutex> lk(mLock);
+    if ((rect.left + rect.width) > static_cast<int>(mWidth) ||
+        (rect.top + rect.height) > static_cast<int>(mHeight) || (rect.left % 2) || (rect.top % 2) ||
+        (rect.width % 2) || (rect.height % 2)) {
+        ALOGE("%s: bad rect left %d top %d w %d h %d", __FUNCTION__, rect.left, rect.top,
+              rect.width, rect.height);
+        return -1;
+    }
+
+    out->y = mData.data() + mWidth * rect.top + rect.left;
+    out->yStride = mWidth;
+    uint8_t* cbStart = mData.data() + mWidth * mHeight;
+    uint8_t* crStart = cbStart + mWidth * mHeight / 4;
+    out->cb = cbStart + mWidth * rect.top / 4 + rect.left / 2;
+    out->cr = crStart + mWidth * rect.top / 4 + rect.left / 2;
+    out->cStride = mWidth / 2;
+    out->chromaStep = 1;
+    return 0;
+}
+
+bool isAspectRatioClose(float ar1, float ar2) {
+    constexpr float kAspectRatioMatchThres = 0.025f;  // This threshold is good enough to
+                                                      // distinguish 4:3/16:9/20:9 1.33/1.78/2
+    return std::abs(ar1 - ar2) < kAspectRatioMatchThres;
+}
+
+aidl::android::hardware::camera::common::Status importBufferImpl(
+        /*inout*/ std::map<int, CirculatingBuffers>& circulatingBuffers,
+        /*inout*/ HandleImporter& handleImporter, int32_t streamId, uint64_t bufId,
+        buffer_handle_t buf,
+        /*out*/ buffer_handle_t** outBufPtr) {
+    using ::aidl::android::hardware::camera::common::Status;
+    if (buf == nullptr && bufId == BUFFER_ID_NO_BUFFER) {
+        ALOGE("%s: bufferId %" PRIu64 " has null buffer handle!", __FUNCTION__, bufId);
+        return Status::ILLEGAL_ARGUMENT;
+    }
+
+    CirculatingBuffers& cbs = circulatingBuffers[streamId];
+    if (cbs.count(bufId) == 0) {
+        if (buf == nullptr) {
+            ALOGE("%s: bufferId %" PRIu64 " has null buffer handle!", __FUNCTION__, bufId);
+            return Status::ILLEGAL_ARGUMENT;
+        }
+        // Register a newly seen buffer
+        buffer_handle_t importedBuf = buf;
+        handleImporter.importBuffer(importedBuf);
+        if (importedBuf == nullptr) {
+            ALOGE("%s: output buffer for stream %d is invalid!", __FUNCTION__, streamId);
+            return Status::INTERNAL_ERROR;
+        } else {
+            cbs[bufId] = importedBuf;
+        }
+    }
+    *outBufPtr = &cbs[bufId];
+    return Status::OK;
+}
+
+uint32_t getFourCcFromLayout(const YCbCrLayout& layout) {
+    intptr_t cb = reinterpret_cast<intptr_t>(layout.cb);
+    intptr_t cr = reinterpret_cast<intptr_t>(layout.cr);
+    if (std::abs(cb - cr) == 1 && layout.chromaStep == 2) {
+        // Interleaved format
+        if (layout.cb > layout.cr) {
+            return V4L2_PIX_FMT_NV21;
+        } else {
+            return V4L2_PIX_FMT_NV12;
+        }
+    } else if (layout.chromaStep == 1) {
+        // Planar format
+        if (layout.cb > layout.cr) {
+            return V4L2_PIX_FMT_YVU420;  // YV12
+        } else {
+            return V4L2_PIX_FMT_YUV420;  // YU12
+        }
+    } else {
+        return FLEX_YUV_GENERIC;
+    }
+}
+
+int getCropRect(CroppingType ct, const Size& inSize, const Size& outSize, IMapper::Rect* out) {
+    if (out == nullptr) {
+        ALOGE("%s: out is null", __FUNCTION__);
+        return -1;
+    }
+
+    uint32_t inW = inSize.width;
+    uint32_t inH = inSize.height;
+    uint32_t outW = outSize.width;
+    uint32_t outH = outSize.height;
+
+    // Handle special case where aspect ratio is close to input but scaled
+    // dimension is slightly larger than input
+    float arIn = ASPECT_RATIO(inSize);
+    float arOut = ASPECT_RATIO(outSize);
+    if (isAspectRatioClose(arIn, arOut)) {
+        out->left = 0;
+        out->top = 0;
+        out->width = static_cast<int32_t>(inW);
+        out->height = static_cast<int32_t>(inH);
+        return 0;
+    }
+
+    if (ct == VERTICAL) {
+        uint64_t scaledOutH = static_cast<uint64_t>(outH) * inW / outW;
+        if (scaledOutH > inH) {
+            ALOGE("%s: Output size %dx%d cannot be vertically cropped from input size %dx%d",
+                  __FUNCTION__, outW, outH, inW, inH);
+            return -1;
+        }
+        scaledOutH = scaledOutH & ~0x1;  // make it multiple of 2
+
+        out->left = 0;
+        out->top = static_cast<int32_t>((inH - scaledOutH) / 2) & ~0x1;
+        out->width = static_cast<int32_t>(inW);
+        out->height = static_cast<int32_t>(scaledOutH);
+        ALOGV("%s: crop %dx%d to %dx%d: top %d, scaledH %d", __FUNCTION__, inW, inH, outW, outH,
+              out->top, static_cast<int32_t>(scaledOutH));
+    } else {
+        uint64_t scaledOutW = static_cast<uint64_t>(outW) * inH / outH;
+        if (scaledOutW > inW) {
+            ALOGE("%s: Output size %dx%d cannot be horizontally cropped from input size %dx%d",
+                  __FUNCTION__, outW, outH, inW, inH);
+            return -1;
+        }
+        scaledOutW = scaledOutW & ~0x1;  // make it multiple of 2
+
+        out->left = static_cast<int32_t>((inW - scaledOutW) / 2) & ~0x1;
+        out->top = 0;
+        out->width = static_cast<int32_t>(scaledOutW);
+        out->height = static_cast<int32_t>(inH);
+        ALOGV("%s: crop %dx%d to %dx%d: top %d, scaledW %d", __FUNCTION__, inW, inH, outW, outH,
+              out->top, static_cast<int32_t>(scaledOutW));
+    }
+
+    return 0;
+}
+
+int formatConvert(const YCbCrLayout& in, const YCbCrLayout& out, Size sz, uint32_t format) {
+    int ret = 0;
+    switch (format) {
+        case V4L2_PIX_FMT_NV21:
+            ret = libyuv::I420ToNV21(
+                    static_cast<uint8_t*>(in.y), static_cast<int32_t>(in.yStride),
+                    static_cast<uint8_t*>(in.cb), static_cast<int32_t>(in.cStride),
+                    static_cast<uint8_t*>(in.cr), static_cast<int32_t>(in.cStride),
+                    static_cast<uint8_t*>(out.y), static_cast<int32_t>(out.yStride),
+                    static_cast<uint8_t*>(out.cr), static_cast<int32_t>(out.cStride),
+                    static_cast<int32_t>(sz.width), static_cast<int32_t>(sz.height));
+            if (ret != 0) {
+                ALOGE("%s: convert to NV21 buffer failed! ret %d", __FUNCTION__, ret);
+                return ret;
+            }
+            break;
+        case V4L2_PIX_FMT_NV12:
+            ret = libyuv::I420ToNV12(
+                    static_cast<uint8_t*>(in.y), static_cast<int32_t>(in.yStride),
+                    static_cast<uint8_t*>(in.cb), static_cast<int32_t>(in.cStride),
+                    static_cast<uint8_t*>(in.cr), static_cast<int32_t>(in.cStride),
+                    static_cast<uint8_t*>(out.y), static_cast<int32_t>(out.yStride),
+                    static_cast<uint8_t*>(out.cb), static_cast<int32_t>(out.cStride),
+                    static_cast<int32_t>(sz.width), static_cast<int32_t>(sz.height));
+            if (ret != 0) {
+                ALOGE("%s: convert to NV12 buffer failed! ret %d", __FUNCTION__, ret);
+                return ret;
+            }
+            break;
+        case V4L2_PIX_FMT_YVU420:  // YV12
+        case V4L2_PIX_FMT_YUV420:  // YU12
+            // TODO: maybe we can speed up here by somehow save this copy?
+            ret = libyuv::I420Copy(static_cast<uint8_t*>(in.y), static_cast<int32_t>(in.yStride),
+                                   static_cast<uint8_t*>(in.cb), static_cast<int32_t>(in.cStride),
+                                   static_cast<uint8_t*>(in.cr), static_cast<int32_t>(in.cStride),
+                                   static_cast<uint8_t*>(out.y), static_cast<int32_t>(out.yStride),
+                                   static_cast<uint8_t*>(out.cb), static_cast<int32_t>(out.cStride),
+                                   static_cast<uint8_t*>(out.cr), static_cast<int32_t>(out.cStride),
+                                   static_cast<int32_t>(sz.width), static_cast<int32_t>(sz.height));
+            if (ret != 0) {
+                ALOGE("%s: copy to YV12 or YU12 buffer failed! ret %d", __FUNCTION__, ret);
+                return ret;
+            }
+            break;
+        case FLEX_YUV_GENERIC:
+            // TODO: b/72261744 write to arbitrary flexible YUV layout. Slow.
+            ALOGE("%s: unsupported flexible yuv layout"
+                  " y %p cb %p cr %p y_str %d c_str %d c_step %d",
+                  __FUNCTION__, out.y, out.cb, out.cr, out.yStride, out.cStride, out.chromaStep);
+            return -1;
+        default:
+            ALOGE("%s: unknown YUV format 0x%x!", __FUNCTION__, format);
+            return -1;
+    }
+    return 0;
+}
+
+int encodeJpegYU12(const Size& inSz, const YCbCrLayout& inLayout, int jpegQuality,
+                   const void* app1Buffer, size_t app1Size, void* out, size_t maxOutSize,
+                   size_t& actualCodeSize) {
+    /* libjpeg is a C library so we use C-style "inheritance" by
+     * putting libjpeg's jpeg_destination_mgr first in our custom
+     * struct. This allows us to cast jpeg_destination_mgr* to
+     * CustomJpegDestMgr* when we get it passed to us in a callback */
+    struct CustomJpegDestMgr {
+        struct jpeg_destination_mgr mgr;
+        JOCTET* mBuffer;
+        size_t mBufferSize;
+        size_t mEncodedSize;
+        bool mSuccess;
+    } dmgr;
+
+    jpeg_compress_struct cinfo = {};
+    jpeg_error_mgr jerr;
+
+    /* Initialize error handling with standard callbacks, but
+     * then override output_message (to print to ALOG) and
+     * error_exit to set a flag and print a message instead
+     * of killing the whole process */
+    cinfo.err = jpeg_std_error(&jerr);
+
+    cinfo.err->output_message = [](j_common_ptr cinfo) {
+        char buffer[JMSG_LENGTH_MAX];
+
+        /* Create the message */
+        (*cinfo->err->format_message)(cinfo, buffer);
+        ALOGE("libjpeg error: %s", buffer);
+    };
+    cinfo.err->error_exit = [](j_common_ptr cinfo) {
+        (*cinfo->err->output_message)(cinfo);
+        if (cinfo->client_data) {
+            auto& dmgr = *reinterpret_cast<CustomJpegDestMgr*>(cinfo->client_data);
+            dmgr.mSuccess = false;
+        }
+    };
+
+    /* Now that we initialized some callbacks, let's create our compressor */
+    jpeg_create_compress(&cinfo);
+
+    /* Initialize our destination manager */
+    dmgr.mBuffer = static_cast<JOCTET*>(out);
+    dmgr.mBufferSize = maxOutSize;
+    dmgr.mEncodedSize = 0;
+    dmgr.mSuccess = true;
+    cinfo.client_data = static_cast<void*>(&dmgr);
+
+    /* These lambdas become C-style function pointers and as per C++11 spec
+     * may not capture anything */
+    dmgr.mgr.init_destination = [](j_compress_ptr cinfo) {
+        auto& dmgr = reinterpret_cast<CustomJpegDestMgr&>(*cinfo->dest);
+        dmgr.mgr.next_output_byte = dmgr.mBuffer;
+        dmgr.mgr.free_in_buffer = dmgr.mBufferSize;
+        ALOGV("%s:%d jpeg start: %p [%zu]", __FUNCTION__, __LINE__, dmgr.mBuffer, dmgr.mBufferSize);
+    };
+
+    dmgr.mgr.empty_output_buffer = [](j_compress_ptr cinfo __unused) {
+        ALOGV("%s:%d Out of buffer", __FUNCTION__, __LINE__);
+        return 0;
+    };
+
+    dmgr.mgr.term_destination = [](j_compress_ptr cinfo) {
+        auto& dmgr = reinterpret_cast<CustomJpegDestMgr&>(*cinfo->dest);
+        dmgr.mEncodedSize = dmgr.mBufferSize - dmgr.mgr.free_in_buffer;
+        ALOGV("%s:%d Done with jpeg: %zu", __FUNCTION__, __LINE__, dmgr.mEncodedSize);
+    };
+    cinfo.dest = reinterpret_cast<struct jpeg_destination_mgr*>(&dmgr);
+
+    /* We are going to be using JPEG in raw data mode, so we are passing
+     * straight subsampled planar YCbCr and it will not touch our pixel
+     * data or do any scaling or anything */
+    cinfo.image_width = inSz.width;
+    cinfo.image_height = inSz.height;
+    cinfo.input_components = 3;
+    cinfo.in_color_space = JCS_YCbCr;
+
+    /* Initialize defaults and then override what we want */
+    jpeg_set_defaults(&cinfo);
+
+    jpeg_set_quality(&cinfo, jpegQuality, 1);
+    jpeg_set_colorspace(&cinfo, JCS_YCbCr);
+    cinfo.raw_data_in = 1;
+    cinfo.dct_method = JDCT_IFAST;
+
+    /* Configure sampling factors. The sampling factor is JPEG subsampling 420
+     * because the source format is YUV420. Note that libjpeg sampling factors
+     * are... a little weird. Sampling of Y=2,U=1,V=1 means there is 1 U and
+     * 1 V value for each 2 Y values */
+    cinfo.comp_info[0].h_samp_factor = 2;
+    cinfo.comp_info[0].v_samp_factor = 2;
+    cinfo.comp_info[1].h_samp_factor = 1;
+    cinfo.comp_info[1].v_samp_factor = 1;
+    cinfo.comp_info[2].h_samp_factor = 1;
+    cinfo.comp_info[2].v_samp_factor = 1;
+
+    /* Start the compressor */
+    jpeg_start_compress(&cinfo, TRUE);
+
+    /* Let's not hardcode YUV420 in 6 places... 5 was enough */
+    int maxVSampFactor = cinfo.max_v_samp_factor;
+    int cVSubSampling = cinfo.comp_info[0].v_samp_factor / cinfo.comp_info[1].v_samp_factor;
+
+    /* Compute our macroblock height, so we can pad our input to be vertically
+     * macroblock aligned. No need to for horizontal alignment since AllocatedFrame already
+     * pads horizontally */
+
+    size_t mcuV = DCTSIZE * maxVSampFactor;
+    size_t paddedHeight = mcuV * ((inSz.height + mcuV - 1) / mcuV);
+
+    /* libjpeg uses arrays of row pointers, which makes it really easy to pad
+     * data vertically (unfortunately doesn't help horizontally) */
+    std::vector<JSAMPROW> yLines(paddedHeight);
+    std::vector<JSAMPROW> cbLines(paddedHeight / cVSubSampling);
+    std::vector<JSAMPROW> crLines(paddedHeight / cVSubSampling);
+
+    uint8_t* py = static_cast<uint8_t*>(inLayout.y);
+    uint8_t* pcb = static_cast<uint8_t*>(inLayout.cb);
+    uint8_t* pcr = static_cast<uint8_t*>(inLayout.cr);
+
+    for (int32_t i = 0; i < paddedHeight; i++) {
+        /* Once we are in the padding territory we still point to the last line
+         * effectively replicating it several times ~ CLAMP_TO_EDGE */
+        int li = std::min(i, inSz.height - 1);
+        yLines[i] = static_cast<JSAMPROW>(py + li * inLayout.yStride);
+        if (i < paddedHeight / cVSubSampling) {
+            li = std::min(i, (inSz.height - 1) / cVSubSampling);
+            cbLines[i] = static_cast<JSAMPROW>(pcb + li * inLayout.cStride);
+            crLines[i] = static_cast<JSAMPROW>(pcr + li * inLayout.cStride);
+        }
+    }
+
+    /* If APP1 data was passed in, use it */
+    if (app1Buffer && app1Size) {
+        jpeg_write_marker(&cinfo, JPEG_APP0 + 1, static_cast<const JOCTET*>(app1Buffer), app1Size);
+    }
+
+    /* While we still have padded height left to go, keep giving it one
+     * macroblock at a time. */
+    while (cinfo.next_scanline < cinfo.image_height) {
+        const uint32_t batchSize = DCTSIZE * maxVSampFactor;
+        const uint32_t nl = cinfo.next_scanline;
+        JSAMPARRAY planes[3]{&yLines[nl], &cbLines[nl / cVSubSampling],
+                             &crLines[nl / cVSubSampling]};
+
+        uint32_t done = jpeg_write_raw_data(&cinfo, planes, batchSize);
+
+        if (done != batchSize) {
+            ALOGE("%s: compressed %u lines, expected %u (total %u/%u)", __FUNCTION__, done,
+                  batchSize, cinfo.next_scanline, cinfo.image_height);
+            return -1;
+        }
+    }
+
+    /* This will flush everything */
+    jpeg_finish_compress(&cinfo);
+
+    /* Grab the actual code size and set it */
+    actualCodeSize = dmgr.mEncodedSize;
+
+    return 0;
+}
+
+Size getMaxThumbnailResolution(const common::V1_0::helper::CameraMetadata& chars) {
+    Size thumbSize{0, 0};
+    camera_metadata_ro_entry entry = chars.find(ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES);
+    for (uint32_t i = 0; i < entry.count; i += 2) {
+        Size sz{.width = entry.data.i32[i], .height = entry.data.i32[i + 1]};
+        if (sz.width * sz.height > thumbSize.width * thumbSize.height) {
+            thumbSize = sz;
+        }
+    }
+
+    if (thumbSize.width * thumbSize.height == 0) {
+        ALOGW("%s: non-zero thumbnail size not available", __FUNCTION__);
+    }
+
+    return thumbSize;
+}
+
+void freeReleaseFences(std::vector<CaptureResult>& results) {
+    for (auto& result : results) {
+        native_handle_t* inputReleaseFence =
+                ::android::makeFromAidl(result.inputBuffer.releaseFence);
+        if (inputReleaseFence != nullptr) {
+            native_handle_close(inputReleaseFence);
+            native_handle_delete(inputReleaseFence);
+        }
+        for (auto& buf : result.outputBuffers) {
+            native_handle_t* outReleaseFence = ::android::makeFromAidl(buf.releaseFence);
+            if (outReleaseFence != nullptr) {
+                native_handle_close(outReleaseFence);
+                native_handle_delete(outReleaseFence);
+            }
+        }
+    }
+}
+
+#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+#define UPDATE(md, tag, data, size)               \
+    do {                                          \
+        if ((md).update((tag), (data), (size))) { \
+            ALOGE("Update " #tag " failed!");     \
+            return BAD_VALUE;                     \
+        }                                         \
+    } while (0)
+
+status_t fillCaptureResultCommon(CameraMetadata& md, nsecs_t timestamp,
+                                 camera_metadata_ro_entry& activeArraySize) {
+    if (activeArraySize.count < 4) {
+        ALOGE("%s: cannot find active array size!", __FUNCTION__);
+        return -EINVAL;
+    }
+    // android.control
+    // For USB camera, we don't know the AE state. Set the state to converged to
+    // indicate the frame should be good to use. Then apps don't have to wait the
+    // AE state.
+    const uint8_t aeState = ANDROID_CONTROL_AE_STATE_CONVERGED;
+    UPDATE(md, ANDROID_CONTROL_AE_STATE, &aeState, 1);
+
+    const uint8_t ae_lock = ANDROID_CONTROL_AE_LOCK_OFF;
+    UPDATE(md, ANDROID_CONTROL_AE_LOCK, &ae_lock, 1);
+
+    // Set AWB state to converged to indicate the frame should be good to use.
+    const uint8_t awbState = ANDROID_CONTROL_AWB_STATE_CONVERGED;
+    UPDATE(md, ANDROID_CONTROL_AWB_STATE, &awbState, 1);
+
+    const uint8_t awbLock = ANDROID_CONTROL_AWB_LOCK_OFF;
+    UPDATE(md, ANDROID_CONTROL_AWB_LOCK, &awbLock, 1);
+
+    const uint8_t flashState = ANDROID_FLASH_STATE_UNAVAILABLE;
+    UPDATE(md, ANDROID_FLASH_STATE, &flashState, 1);
+
+    // This means pipeline latency of X frame intervals. The maximum number is 4.
+    const uint8_t requestPipelineMaxDepth = 4;
+    UPDATE(md, ANDROID_REQUEST_PIPELINE_DEPTH, &requestPipelineMaxDepth, 1);
+
+    // android.scaler
+    const int32_t crop_region[] = {
+            activeArraySize.data.i32[0],
+            activeArraySize.data.i32[1],
+            activeArraySize.data.i32[2],
+            activeArraySize.data.i32[3],
+    };
+    UPDATE(md, ANDROID_SCALER_CROP_REGION, crop_region, ARRAY_SIZE(crop_region));
+
+    // android.sensor
+    UPDATE(md, ANDROID_SENSOR_TIMESTAMP, &timestamp, 1);
+
+    // android.statistics
+    const uint8_t lensShadingMapMode = ANDROID_STATISTICS_LENS_SHADING_MAP_MODE_OFF;
+    UPDATE(md, ANDROID_STATISTICS_LENS_SHADING_MAP_MODE, &lensShadingMapMode, 1);
+
+    const uint8_t sceneFlicker = ANDROID_STATISTICS_SCENE_FLICKER_NONE;
+    UPDATE(md, ANDROID_STATISTICS_SCENE_FLICKER, &sceneFlicker, 1);
+
+    return OK;
+}
+
+#undef ARRAY_SIZE
+#undef UPDATE
+
+AllocatedV4L2Frame::AllocatedV4L2Frame(std::shared_ptr<V4L2Frame> frameIn)
+    : Frame(frameIn->mWidth, frameIn->mHeight, frameIn->mFourcc) {
+    uint8_t* dataIn;
+    size_t dataSize;
+    if (frameIn->getData(&dataIn, &dataSize) != 0) {
+        ALOGE("%s: map input V4L2 frame failed!", __FUNCTION__);
+        return;
+    }
+
+    mData.resize(dataSize);
+    std::memcpy(mData.data(), dataIn, dataSize);
+}
+
+AllocatedV4L2Frame::~AllocatedV4L2Frame() {}
+
+int AllocatedV4L2Frame::getData(uint8_t** outData, size_t* dataSize) {
+    if (outData == nullptr || dataSize == nullptr) {
+        ALOGE("%s: outData(%p)/dataSize(%p) must not be null", __FUNCTION__, outData, dataSize);
+        return -1;
+    }
+
+    *outData = mData.data();
+    *dataSize = mData.size();
+    return 0;
+}
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/camera/device/default/ExternalCameraUtils.h b/camera/device/default/ExternalCameraUtils.h
new file mode 100644
index 0000000..b37933c
--- /dev/null
+++ b/camera/device/default/ExternalCameraUtils.h
@@ -0,0 +1,300 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAUTILS_H_
+#define HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAUTILS_H_
+
+#include <CameraMetadata.h>
+#include <HandleImporter.h>
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <aidl/android/hardware/camera/device/CaptureResult.h>
+#include <aidl/android/hardware/camera/device/ErrorCode.h>
+#include <aidl/android/hardware/camera/device/NotifyMsg.h>
+#include <aidl/android/hardware/graphics/common/BufferUsage.h>
+#include <aidl/android/hardware/graphics/common/PixelFormat.h>
+#include <tinyxml2.h>
+#include <unordered_map>
+#include <unordered_set>
+
+using ::aidl::android::hardware::camera::common::Status;
+using ::aidl::android::hardware::camera::device::CaptureResult;
+using ::aidl::android::hardware::camera::device::ErrorCode;
+using ::aidl::android::hardware::camera::device::NotifyMsg;
+using ::aidl::android::hardware::graphics::common::BufferUsage;
+using ::aidl::android::hardware::graphics::common::PixelFormat;
+using ::android::hardware::camera::common::V1_0::helper::CameraMetadata;
+using ::android::hardware::camera::common::V1_0::helper::HandleImporter;
+
+namespace android {
+namespace hardware {
+namespace camera {
+
+namespace external {
+namespace common {
+
+struct Size {
+    int32_t width;
+    int32_t height;
+
+    bool operator==(const Size& other) const {
+        return (width == other.width && height == other.height);
+    }
+};
+
+struct SizeHasher {
+    size_t operator()(const Size& sz) const {
+        size_t result = 1;
+        result = 31 * result + sz.width;
+        result = 31 * result + sz.height;
+        return result;
+    }
+};
+
+struct ExternalCameraConfig {
+    static const char* kDefaultCfgPath;
+    static ExternalCameraConfig loadFromCfg(const char* cfgPath = kDefaultCfgPath);
+
+    // CameraId base offset for numerical representation
+    uint32_t cameraIdOffset;
+
+    // List of internal V4L2 video nodes external camera HAL must ignore.
+    std::unordered_set<std::string> mInternalDevices;
+
+    // Maximal size of a JPEG buffer, in bytes
+    int32_t maxJpegBufSize;
+
+    // Maximum Size that can sustain 30fps streaming
+    Size maxVideoSize;
+
+    // Size of v4l2 buffer queue when streaming <= kMaxVideoSize
+    uint32_t numVideoBuffers;
+
+    // Size of v4l2 buffer queue when streaming > kMaxVideoSize
+    uint32_t numStillBuffers;
+
+    // Indication that the device connected supports depth output
+    bool depthEnabled;
+
+    struct FpsLimitation {
+        Size size;
+        double fpsUpperBound;
+    };
+    std::vector<FpsLimitation> fpsLimits;
+    std::vector<FpsLimitation> depthFpsLimits;
+
+    // Minimum output stream size
+    Size minStreamSize;
+
+    // The value of android.sensor.orientation
+    int32_t orientation;
+
+  private:
+    ExternalCameraConfig();
+    static bool updateFpsList(tinyxml2::XMLElement* fpsList, std::vector<FpsLimitation>& fpsLimits);
+};
+
+}  // namespace common
+}  // namespace external
+
+namespace device {
+namespace implementation {
+
+struct SupportedV4L2Format {
+    int32_t width;
+    int32_t height;
+    uint32_t fourcc;
+    // All supported frame rate for this w/h/fourcc combination
+    struct FrameRate {
+        // Duration (in seconds) of a single frame.
+        // Numerator and denominator of the frame duration are stored separately.
+        // For ex. a frame lasting 1/30 of a second will be stored as {1, 30}
+        uint32_t durationNumerator;         // frame duration numerator.   Ex: 1
+        uint32_t durationDenominator;       // frame duration denominator. Ex: 30
+        double getFramesPerSecond() const;  // FPS as double.        Ex: 30.0
+    };
+    std::vector<FrameRate> frameRates;
+};
+
+// A Base class with basic information about a frame
+struct Frame : public std::enable_shared_from_this<Frame> {
+  public:
+    Frame(uint32_t width, uint32_t height, uint32_t fourcc);
+    virtual ~Frame();
+    const int32_t mWidth;
+    const int32_t mHeight;
+    const uint32_t mFourcc;
+
+    // getData might involve map/allocation
+    virtual int getData(uint8_t** outData, size_t* dataSize) = 0;
+};
+
+// A class provide access to a dequeued V4L2 frame buffer (mostly in MJPG format)
+// Also contains necessary information to enqueue the buffer back to V4L2 buffer queue
+class V4L2Frame : public Frame {
+  public:
+    V4L2Frame(uint32_t w, uint32_t h, uint32_t fourcc, int bufIdx, int fd, uint32_t dataSize,
+              uint64_t offset);
+    virtual ~V4L2Frame();
+
+    virtual int getData(uint8_t** outData, size_t* dataSize) override;
+
+    const int mBufferIndex;  // for later enqueue
+    int map(uint8_t** data, size_t* dataSize);
+    int unmap();
+
+  private:
+    std::mutex mLock;
+    const int mFd;  // used for mmap but doesn't claim ownership
+    const size_t mDataSize;
+    const uint64_t mOffset;  // used for mmap
+    uint8_t* mData = nullptr;
+    bool mMapped = false;
+};
+
+// A RAII class representing a CPU allocated YUV frame used as intermediate buffers
+// when generating output images.
+class AllocatedFrame : public Frame {
+  public:
+    AllocatedFrame(uint32_t w, uint32_t h);  // only support V4L2_PIX_FMT_YUV420 for now
+    ~AllocatedFrame() override;
+
+    virtual int getData(uint8_t** outData, size_t* dataSize) override;
+
+    int allocate(YCbCrLayout* out = nullptr);
+    int getLayout(YCbCrLayout* out);
+    int getCroppedLayout(const IMapper::Rect&, YCbCrLayout* out);  // return non-zero for bad input
+  private:
+    std::mutex mLock;
+    std::vector<uint8_t> mData;
+    size_t mBufferSize;  // size of mData before padding. Actual size of mData might be slightly
+                         // bigger to horizontally pad the frame for jpeglib.
+};
+
+enum CroppingType { HORIZONTAL = 0, VERTICAL = 1 };
+
+// Aspect ratio is defined as width/height here and ExternalCameraDevice
+// will guarantee all supported sizes has width >= height (so aspect ratio >= 1.0)
+#define ASPECT_RATIO(sz) (static_cast<float>((sz).width) / (sz).height)
+const float kMaxAspectRatio = std::numeric_limits<float>::max();
+const float kMinAspectRatio = 1.f;
+
+bool isAspectRatioClose(float ar1, float ar2);
+
+struct HalStreamBuffer {
+    int32_t streamId;
+    int64_t bufferId;
+    int32_t width;
+    int32_t height;
+    ::aidl::android::hardware::graphics::common::PixelFormat format;
+    ::aidl::android::hardware::graphics::common::BufferUsage usage;
+    buffer_handle_t* bufPtr;
+    int acquireFence;
+    bool fenceTimeout;
+};
+
+struct HalRequest {
+    int32_t frameNumber;
+    common::V1_0::helper::CameraMetadata setting;
+    std::shared_ptr<Frame> frameIn;
+    nsecs_t shutterTs;
+    std::vector<HalStreamBuffer> buffers;
+};
+
+static const uint64_t BUFFER_ID_NO_BUFFER = 0;
+
+// buffers currently circulating between HAL and camera service
+// key: bufferId sent via HIDL interface
+// value: imported buffer_handle_t
+// Buffer will be imported during processCaptureRequest (or requestStreamBuffer
+// in the case of HAL buffer manager is enabled) and will be freed
+// when the stream is deleted or camera device session is closed
+typedef std::unordered_map<uint64_t, buffer_handle_t> CirculatingBuffers;
+
+aidl::android::hardware::camera::common::Status importBufferImpl(
+        /*inout*/ std::map<int, CirculatingBuffers>& circulatingBuffers,
+        /*inout*/ HandleImporter& handleImporter, int32_t streamId, uint64_t bufId,
+        buffer_handle_t buf,
+        /*out*/ buffer_handle_t** outBufPtr);
+
+static const uint32_t FLEX_YUV_GENERIC =
+        static_cast<uint32_t>('F') | static_cast<uint32_t>('L') << 8 |
+        static_cast<uint32_t>('E') << 16 | static_cast<uint32_t>('X') << 24;
+
+// returns FLEX_YUV_GENERIC for formats other than YV12/YU12/NV12/NV21
+uint32_t getFourCcFromLayout(const YCbCrLayout&);
+
+using ::android::hardware::camera::external::common::Size;
+int getCropRect(CroppingType ct, const Size& inSize, const Size& outSize, IMapper::Rect* out);
+
+int formatConvert(const YCbCrLayout& in, const YCbCrLayout& out, Size sz, uint32_t format);
+
+int encodeJpegYU12(const Size& inSz, const YCbCrLayout& inLayout, int jpegQuality,
+                   const void* app1Buffer, size_t app1Size, void* out, size_t maxOutSize,
+                   size_t& actualCodeSize);
+
+Size getMaxThumbnailResolution(const common::V1_0::helper::CameraMetadata&);
+
+void freeReleaseFences(std::vector<CaptureResult>&);
+
+status_t fillCaptureResultCommon(common::V1_0::helper::CameraMetadata& md, nsecs_t timestamp,
+                                 camera_metadata_ro_entry& activeArraySize);
+
+// Interface for OutputThread calling back to parent
+struct OutputThreadInterface {
+    virtual ~OutputThreadInterface() {}
+    virtual aidl::android::hardware::camera::common::Status importBuffer(
+            int32_t streamId, uint64_t bufId, buffer_handle_t buf,
+            /*out*/ buffer_handle_t** outBufPtr) = 0;
+
+    virtual void notifyError(int32_t frameNumber, int32_t streamId, ErrorCode ec) = 0;
+
+    // Callbacks are fired within the method if msgs/results are nullptr.
+    // Otherwise the callbacks will be returned and caller is responsible to
+    // fire the callback later
+    virtual aidl::android::hardware::camera::common::Status processCaptureRequestError(
+            const std::shared_ptr<HalRequest>&,
+            /*out*/ std::vector<NotifyMsg>* msgs,
+            /*out*/ std::vector<CaptureResult>* results) = 0;
+
+    virtual aidl::android::hardware::camera::common::Status processCaptureRequestError(
+            const std::shared_ptr<HalRequest>& reqs) final {
+        return processCaptureRequestError(reqs, nullptr, nullptr);
+    }
+
+    virtual aidl::android::hardware::camera::common::Status processCaptureResult(
+            std::shared_ptr<HalRequest>&) = 0;
+
+    virtual ssize_t getJpegBufferSize(int32_t width, int32_t height) const = 0;
+};
+
+// A CPU copy of a mapped V4L2Frame. Will map the input V4L2 frame.
+class AllocatedV4L2Frame : public Frame {
+  public:
+    AllocatedV4L2Frame(std::shared_ptr<V4L2Frame> frameIn);
+    ~AllocatedV4L2Frame() override;
+    virtual int getData(uint8_t** outData, size_t* dataSize) override;
+
+  private:
+    std::vector<uint8_t> mData;
+};
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_EXTERNALCAMERAUTILS_H_
diff --git a/camera/device/default/OWNERS b/camera/device/default/OWNERS
new file mode 100644
index 0000000..f48a95c
--- /dev/null
+++ b/camera/device/default/OWNERS
@@ -0,0 +1 @@
+include platform/frameworks/av:/camera/OWNERS
diff --git a/camera/device/default/convert.cpp b/camera/device/default/convert.cpp
new file mode 100644
index 0000000..8134dd5
--- /dev/null
+++ b/camera/device/default/convert.cpp
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "android.hardware.camera.device@3.4-convert-impl"
+#include <log/log.h>
+
+#include "convert.h"
+
+#include <aidl/android/hardware/graphics/common/BufferUsage.h>
+#include <aidl/android/hardware/graphics/common/PixelFormat.h>
+#include <hardware/camera_common.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::device::ErrorCode;
+using ::aidl::android::hardware::camera::device::ErrorMsg;
+using ::aidl::android::hardware::camera::device::ShutterMsg;
+using ::aidl::android::hardware::graphics::common::BufferUsage;
+using ::aidl::android::hardware::graphics::common::PixelFormat;
+
+void convertToAidl(const camera_metadata_t* src, CameraMetadata* dest) {
+    if (src == nullptr) {
+        return;
+    }
+
+    size_t size = get_camera_metadata_size(src);
+    auto* src_start = (uint8_t*)src;
+    uint8_t* src_end = src_start + size;
+    dest->metadata.assign(src_start, src_end);
+}
+
+bool convertFromAidl(const CameraMetadata& src, const camera_metadata_t** dst) {
+    const std::vector<uint8_t>& metadata = src.metadata;
+    if (metadata.empty()) {
+        // Special case for null metadata
+        *dst = nullptr;
+        return true;
+    }
+
+    const uint8_t* data = metadata.data();
+    // check that the size of CameraMetadata match underlying camera_metadata_t
+    if (get_camera_metadata_size((camera_metadata_t*)data) != metadata.size()) {
+        ALOGE("%s: input CameraMetadata is corrupt!", __FUNCTION__);
+        return false;
+    }
+    *dst = (camera_metadata_t*)data;
+    return true;
+}
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
diff --git a/camera/device/default/convert.h b/camera/device/default/convert.h
new file mode 100644
index 0000000..5a508fc
--- /dev/null
+++ b/camera/device/default/convert.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_CONVERT_H_
+#define HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_CONVERT_H_
+
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <aidl/android/hardware/camera/device/BufferStatus.h>
+#include <aidl/android/hardware/camera/device/CameraMetadata.h>
+#include <aidl/android/hardware/camera/device/HalStream.h>
+#include <aidl/android/hardware/camera/device/NotifyMsg.h>
+#include <aidl/android/hardware/camera/device/Stream.h>
+#include <hardware/camera3.h>
+#include <system/camera_metadata.h>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace device {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::Status;
+using ::aidl::android::hardware::camera::device::BufferStatus;
+using ::aidl::android::hardware::camera::device::CameraMetadata;
+using ::aidl::android::hardware::camera::device::HalStream;
+using ::aidl::android::hardware::camera::device::NotifyMsg;
+using ::aidl::android::hardware::camera::device::Stream;
+
+void convertToAidl(const camera_metadata_t* src, CameraMetadata* dest);
+
+bool convertFromAidl(const CameraMetadata& src, const camera_metadata_t** dst);
+
+inline ndk::ScopedAStatus fromStatus(Status status) {
+    return status == Status::OK
+                   ? ndk::ScopedAStatus::ok()
+                   : ndk::ScopedAStatus::fromServiceSpecificError(static_cast<int32_t>(status));
+}
+
+}  // namespace implementation
+}  // namespace device
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_DEVICE_DEFAULT_CONVERT_H_
diff --git a/camera/provider/default/Android.bp b/camera/provider/default/Android.bp
new file mode 100644
index 0000000..ed45cbe
--- /dev/null
+++ b/camera/provider/default/Android.bp
@@ -0,0 +1,104 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+package {
+    // See: http://go/android-license-faq
+    // A large-scale-change added 'default_applicable_licenses' to import
+    // all of the 'license_kinds' from "hardware_interfaces_license"
+    // to get the below license kinds:
+    //   SPDX-license-identifier-Apache-2.0
+    default_applicable_licenses: ["hardware_interfaces_license"],
+}
+
+cc_library_shared {
+    name: "android.hardware.camera.provider-V1-external-impl",
+    defaults: ["hidl_defaults"],
+    proprietary: true,
+    srcs: [
+        "ExternalCameraProvider.cpp",
+    ],
+    shared_libs: [
+        "android.hardware.camera.common-V1-ndk",
+        "android.hardware.camera.device-V1-ndk",
+        "android.hardware.camera.provider-V1-ndk",
+        "android.hardware.graphics.mapper@2.0",
+        "android.hardware.graphics.mapper@3.0",
+        "android.hardware.graphics.mapper@4.0",
+        "android.hidl.allocator@1.0",
+        "android.hidl.memory@1.0",
+        "camera.device-external-impl",
+        "libbinder_ndk",
+        "libcamera_metadata",
+        "libcutils",
+        "libfmq",
+        "libhardware",
+        "libhidlbase",
+        "liblog",
+        "libtinyxml2",
+        "libutils",
+    ],
+    static_libs: [
+        "android.hardware.camera.common@1.0-helper",
+    ],
+    export_include_dirs: ["."],
+}
+
+cc_defaults {
+    name: "camera_external_service_defaults",
+    defaults: ["hidl_defaults"],
+    proprietary: true,
+    relative_install_path: "hw",
+    srcs: ["external-service.cpp"],
+    compile_multilib: "first",
+    shared_libs: [
+        "android.hardware.camera.common-V1-ndk",
+        "android.hardware.camera.device-V1-ndk",
+        "android.hardware.camera.provider-V1-ndk",
+        "android.hardware.camera.provider-V1-external-impl",
+        "android.hardware.graphics.mapper@2.0",
+        "android.hardware.graphics.mapper@3.0",
+        "android.hardware.graphics.mapper@4.0",
+        "android.hidl.allocator@1.0",
+        "android.hidl.memory@1.0",
+        "camera.device-external-impl",
+        "libbinder_ndk",
+        "libcamera_metadata",
+        "libcutils",
+        "libfmq",
+        "libhardware",
+        "libhidlbase",
+        "liblog",
+        "libtinyxml2",
+        "libutils",
+    ],
+    static_libs: [
+        "android.hardware.camera.common@1.0-helper",
+    ],
+}
+
+cc_binary {
+    name: "android.hardware.camera.provider-V1-external-service",
+    defaults: ["camera_external_service_defaults"],
+    init_rc: ["android.hardware.camera.provider-V1-external-service.rc"],
+}
+
+cc_binary {
+    name: "android.hardware.camera.provider-V1-external-service-lazy",
+    overrides: ["android.hardware.camera.provider-V1-external-service"],
+    defaults: ["camera_external_service_defaults"],
+    init_rc: ["android.hardware.camera.provider-V1-external-service-lazy.rc"],
+    cflags: ["-DLAZY_SERVICE"],
+}
diff --git a/camera/provider/default/ExternalCameraProvider.cpp b/camera/provider/default/ExternalCameraProvider.cpp
new file mode 100644
index 0000000..d47ddbf
--- /dev/null
+++ b/camera/provider/default/ExternalCameraProvider.cpp
@@ -0,0 +1,382 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "ExtCamPrvdr"
+// #define LOG_NDEBUG 0
+
+#include "ExternalCameraProvider.h"
+
+#include <ExternalCameraDevice.h>
+#include <aidl/android/hardware/camera/common/Status.h>
+#include <convert.h>
+#include <cutils/properties.h>
+#include <linux/videodev2.h>
+#include <log/log.h>
+#include <sys/inotify.h>
+#include <regex>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace provider {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::Status;
+using ::android::hardware::camera::device::implementation::ExternalCameraDevice;
+using ::android::hardware::camera::device::implementation::fromStatus;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+
+namespace {
+// "device@<version>/external/<id>"
+const std::regex kDeviceNameRE("device@([0-9]+\\.[0-9]+)/external/(.+)");
+const int kMaxDevicePathLen = 256;
+constexpr char kDevicePath[] = "/dev/";
+constexpr char kPrefix[] = "video";
+constexpr int kPrefixLen = sizeof(kPrefix) - 1;
+constexpr int kDevicePrefixLen = sizeof(kDevicePath) + kPrefixLen + 1;
+
+bool matchDeviceName(int cameraIdOffset, const std::string& deviceName, std::string* deviceVersion,
+                     std::string* cameraDevicePath) {
+    std::smatch sm;
+    if (std::regex_match(deviceName, sm, kDeviceNameRE)) {
+        if (deviceVersion != nullptr) {
+            *deviceVersion = sm[1];
+        }
+        if (cameraDevicePath != nullptr) {
+            *cameraDevicePath = "/dev/video" + std::to_string(std::stoi(sm[2]) - cameraIdOffset);
+        }
+        return true;
+    }
+    return false;
+}
+}  // namespace
+
+ExternalCameraProvider::ExternalCameraProvider() : mCfg(ExternalCameraConfig::loadFromCfg()) {
+    mHotPlugThread = std::make_shared<HotplugThread>(this);
+    mHotPlugThread->run();
+}
+
+ExternalCameraProvider::~ExternalCameraProvider() {
+    mHotPlugThread->requestExitAndWait();
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::setCallback(
+        const std::shared_ptr<ICameraProviderCallback>& in_callback) {
+    {
+        Mutex::Autolock _l(mLock);
+        mCallback = in_callback;
+    }
+
+    if (mCallback == nullptr) {
+        return fromStatus(Status::OK);
+    }
+
+    for (const auto& pair : mCameraStatusMap) {
+        mCallback->cameraDeviceStatusChange(pair.first, pair.second);
+    }
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::getVendorTags(
+        std::vector<VendorTagSection>* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+    // No vendor tag support for USB camera
+    *_aidl_return = {};
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::getCameraIdList(std::vector<std::string>* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+    // External camera HAL always report 0 camera, and extra cameras
+    // are just reported via cameraDeviceStatusChange callbacks
+    *_aidl_return = {};
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::getCameraDeviceInterface(
+        const std::string& in_cameraDeviceName, std::shared_ptr<ICameraDevice>* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+    std::string cameraDevicePath, deviceVersion;
+    bool match = matchDeviceName(mCfg.cameraIdOffset, in_cameraDeviceName, &deviceVersion,
+                                 &cameraDevicePath);
+
+    if (!match) {
+        *_aidl_return = nullptr;
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    if (mCameraStatusMap.count(in_cameraDeviceName) == 0 ||
+        mCameraStatusMap[in_cameraDeviceName] != CameraDeviceStatus::PRESENT) {
+        *_aidl_return = nullptr;
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+
+    ALOGV("Constructing external camera device");
+    std::shared_ptr<ExternalCameraDevice> deviceImpl =
+            ndk::SharedRefBase::make<ExternalCameraDevice>(cameraDevicePath, mCfg);
+    if (deviceImpl == nullptr || deviceImpl->isInitFailed()) {
+        ALOGE("%s: camera device %s init failed!", __FUNCTION__, cameraDevicePath.c_str());
+        *_aidl_return = nullptr;
+        return fromStatus(Status::INTERNAL_ERROR);
+    }
+
+    IF_ALOGV() {
+        int interfaceVersion;
+        deviceImpl->getInterfaceVersion(&interfaceVersion);
+        ALOGV("%s: device interface version: %d", __FUNCTION__, interfaceVersion);
+    }
+
+    *_aidl_return = deviceImpl;
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::notifyDeviceStateChange(int64_t) {
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::getConcurrentCameraIds(
+        std::vector<ConcurrentCameraIdCombination>* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+    *_aidl_return = {};
+    return fromStatus(Status::OK);
+}
+
+ndk::ScopedAStatus ExternalCameraProvider::isConcurrentStreamCombinationSupported(
+        const std::vector<CameraIdAndStreamCombination>&, bool* _aidl_return) {
+    if (_aidl_return == nullptr) {
+        return fromStatus(Status::ILLEGAL_ARGUMENT);
+    }
+    // No concurrent stream combinations are supported
+    *_aidl_return = false;
+    return fromStatus(Status::OK);
+}
+
+void ExternalCameraProvider::addExternalCamera(const char* devName) {
+    ALOGV("%s: ExtCam: adding %s to External Camera HAL!", __FUNCTION__, devName);
+    Mutex::Autolock _l(mLock);
+    std::string deviceName;
+    std::string cameraId =
+            std::to_string(mCfg.cameraIdOffset + std::atoi(devName + kDevicePrefixLen));
+    deviceName =
+            std::string("device@") + ExternalCameraDevice::kDeviceVersion + "/external/" + cameraId;
+    mCameraStatusMap[deviceName] = CameraDeviceStatus::PRESENT;
+    if (mCallback != nullptr) {
+        mCallback->cameraDeviceStatusChange(deviceName, CameraDeviceStatus::PRESENT);
+    }
+}
+
+void ExternalCameraProvider::deviceAdded(const char* devName) {
+    {
+        base::unique_fd fd(::open(devName, O_RDWR));
+        if (fd.get() < 0) {
+            ALOGE("%s open v4l2 device %s failed:%s", __FUNCTION__, devName, strerror(errno));
+            return;
+        }
+
+        struct v4l2_capability capability;
+        int ret = ioctl(fd.get(), VIDIOC_QUERYCAP, &capability);
+        if (ret < 0) {
+            ALOGE("%s v4l2 QUERYCAP %s failed", __FUNCTION__, devName);
+            return;
+        }
+
+        if (!(capability.device_caps & V4L2_CAP_VIDEO_CAPTURE)) {
+            ALOGW("%s device %s does not support VIDEO_CAPTURE", __FUNCTION__, devName);
+            return;
+        }
+    }
+
+    // See if we can initialize ExternalCameraDevice correctly
+    std::shared_ptr<ExternalCameraDevice> deviceImpl =
+            ndk::SharedRefBase::make<ExternalCameraDevice>(devName, mCfg);
+    if (deviceImpl == nullptr || deviceImpl->isInitFailed()) {
+        ALOGW("%s: Attempt to init camera device %s failed!", __FUNCTION__, devName);
+        return;
+    }
+    deviceImpl.reset();
+    addExternalCamera(devName);
+}
+
+void ExternalCameraProvider::deviceRemoved(const char* devName) {
+    Mutex::Autolock _l(mLock);
+    std::string deviceName;
+    std::string cameraId =
+            std::to_string(mCfg.cameraIdOffset + std::atoi(devName + kDevicePrefixLen));
+
+    deviceName =
+            std::string("device@") + ExternalCameraDevice::kDeviceVersion + "/external/" + cameraId;
+
+    if (mCameraStatusMap.erase(deviceName) == 0) {
+        // Unknown device, do not fire callback
+        ALOGE("%s: cannot find camera device to remove %s", __FUNCTION__, devName);
+        return;
+    }
+
+    if (mCallback != nullptr) {
+        mCallback->cameraDeviceStatusChange(deviceName, CameraDeviceStatus::NOT_PRESENT);
+    }
+}
+
+void ExternalCameraProvider::updateAttachedCameras() {
+    ALOGV("%s start scanning for existing V4L2 devices", __FUNCTION__);
+
+    // Find existing /dev/video* devices
+    DIR* devdir = opendir(kDevicePath);
+    if (devdir == nullptr) {
+        ALOGE("%s: cannot open %s! Exiting threadloop", __FUNCTION__, kDevicePath);
+        return;
+    }
+
+    struct dirent* de;
+    while ((de = readdir(devdir)) != nullptr) {
+        // Find external v4l devices that's existing before we start watching and add them
+        if (!strncmp(kPrefix, de->d_name, kPrefixLen)) {
+            std::string deviceId(de->d_name + kPrefixLen);
+            if (mCfg.mInternalDevices.count(deviceId) == 0) {
+                ALOGV("Non-internal v4l device %s found", de->d_name);
+                char v4l2DevicePath[kMaxDevicePathLen];
+                snprintf(v4l2DevicePath, kMaxDevicePathLen, "%s%s", kDevicePath, de->d_name);
+                deviceAdded(v4l2DevicePath);
+            }
+        }
+    }
+    closedir(devdir);
+}
+
+// Start ExternalCameraProvider::HotplugThread functions
+
+ExternalCameraProvider::HotplugThread::HotplugThread(ExternalCameraProvider* parent)
+    : mParent(parent), mInternalDevices(parent->mCfg.mInternalDevices) {}
+
+ExternalCameraProvider::HotplugThread::~HotplugThread() {
+    // Clean up inotify descriptor if needed.
+    if (mINotifyFD >= 0) {
+        close(mINotifyFD);
+    }
+}
+
+bool ExternalCameraProvider::HotplugThread::initialize() {
+    // Update existing cameras
+    mParent->updateAttachedCameras();
+
+    // Set up non-blocking fd. The threadLoop will be responsible for polling read at the
+    // desired frequency
+    mINotifyFD = inotify_init();
+    if (mINotifyFD < 0) {
+        ALOGE("%s: inotify init failed! Exiting threadloop", __FUNCTION__);
+        return false;
+    }
+
+    // Start watching /dev/ directory for created and deleted files
+    mWd = inotify_add_watch(mINotifyFD, kDevicePath, IN_CREATE | IN_DELETE);
+    if (mWd < 0) {
+        ALOGE("%s: inotify add watch failed! Exiting threadloop", __FUNCTION__);
+        return false;
+    }
+
+    mPollFd = {.fd = mINotifyFD, .events = POLLIN};
+
+    mIsInitialized = true;
+    return true;
+}
+
+bool ExternalCameraProvider::HotplugThread::threadLoop() {
+    // Initialize inotify descriptors if needed.
+    if (!mIsInitialized && !initialize()) {
+        return true;
+    }
+
+    // poll /dev/* and handle timeouts and error
+    int pollRet = poll(&mPollFd, /* fd_count= */ 1, /* timeout= */ 250);
+    if (pollRet == 0) {
+        // no read event in 100ms
+        mPollFd.revents = 0;
+        return true;
+    } else if (pollRet < 0) {
+        ALOGE("%s: error while polling for /dev/*: %d", __FUNCTION__, errno);
+        mPollFd.revents = 0;
+        return true;
+    } else if (mPollFd.revents & POLLERR) {
+        ALOGE("%s: polling /dev/ returned POLLERR", __FUNCTION__);
+        mPollFd.revents = 0;
+        return true;
+    } else if (mPollFd.revents & POLLHUP) {
+        ALOGE("%s: polling /dev/ returned POLLHUP", __FUNCTION__);
+        mPollFd.revents = 0;
+        return true;
+    } else if (mPollFd.revents & POLLNVAL) {
+        ALOGE("%s: polling /dev/ returned POLLNVAL", __FUNCTION__);
+        mPollFd.revents = 0;
+        return true;
+    }
+    // mPollFd.revents must contain POLLIN, so safe to reset it before reading
+    mPollFd.revents = 0;
+
+    uint64_t offset = 0;
+    ssize_t ret = read(mINotifyFD, mEventBuf, sizeof(mEventBuf));
+    if (ret < sizeof(struct inotify_event)) {
+        // invalid event. skip
+        return true;
+    }
+
+    while (offset < ret) {
+        struct inotify_event* event = (struct inotify_event*)&mEventBuf[offset];
+        offset += sizeof(struct inotify_event) + event->len;
+
+        if (event->wd != mWd) {
+            // event for an unrelated descriptor. ignore.
+            continue;
+        }
+
+        ALOGV("%s inotify_event %s", __FUNCTION__, event->name);
+        if (strncmp(kPrefix, event->name, kPrefixLen) != 0) {
+            // event not for /dev/video*. ignore.
+            continue;
+        }
+
+        std::string deviceId = event->name + kPrefixLen;
+        if (mInternalDevices.count(deviceId) != 0) {
+            // update to an internal device. ignore.
+            continue;
+        }
+
+        char v4l2DevicePath[kMaxDevicePathLen];
+        snprintf(v4l2DevicePath, kMaxDevicePathLen, "%s%s", kDevicePath, event->name);
+
+        if (event->mask & IN_CREATE) {
+            mParent->deviceAdded(v4l2DevicePath);
+        } else if (event->mask & IN_DELETE) {
+            mParent->deviceRemoved(v4l2DevicePath);
+        }
+    }
+    return true;
+}
+
+// End ExternalCameraProvider::HotplugThread functions
+
+}  // namespace implementation
+}  // namespace provider
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
\ No newline at end of file
diff --git a/camera/provider/default/ExternalCameraProvider.h b/camera/provider/default/ExternalCameraProvider.h
new file mode 100644
index 0000000..347a53c
--- /dev/null
+++ b/camera/provider/default/ExternalCameraProvider.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
+#define HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
+
+#include <ExternalCameraUtils.h>
+#include <SimpleThread.h>
+#include <aidl/android/hardware/camera/common/CameraDeviceStatus.h>
+#include <aidl/android/hardware/camera/common/VendorTagSection.h>
+#include <aidl/android/hardware/camera/device/ICameraDevice.h>
+#include <aidl/android/hardware/camera/provider/BnCameraProvider.h>
+#include <aidl/android/hardware/camera/provider/CameraIdAndStreamCombination.h>
+#include <aidl/android/hardware/camera/provider/ConcurrentCameraIdCombination.h>
+#include <aidl/android/hardware/camera/provider/ICameraProviderCallback.h>
+#include <poll.h>
+#include <utils/Mutex.h>
+#include <utils/Thread.h>
+#include <thread>
+#include <unordered_map>
+#include <unordered_set>
+
+namespace android {
+namespace hardware {
+namespace camera {
+namespace provider {
+namespace implementation {
+
+using ::aidl::android::hardware::camera::common::CameraDeviceStatus;
+using ::aidl::android::hardware::camera::common::VendorTagSection;
+using ::aidl::android::hardware::camera::device::ICameraDevice;
+using ::aidl::android::hardware::camera::provider::BnCameraProvider;
+using ::aidl::android::hardware::camera::provider::CameraIdAndStreamCombination;
+using ::aidl::android::hardware::camera::provider::ConcurrentCameraIdCombination;
+using ::aidl::android::hardware::camera::provider::ICameraProviderCallback;
+using ::android::hardware::camera::common::helper::SimpleThread;
+using ::android::hardware::camera::external::common::ExternalCameraConfig;
+
+class ExternalCameraProvider : public BnCameraProvider {
+  public:
+    ExternalCameraProvider();
+    ~ExternalCameraProvider() override;
+    ndk::ScopedAStatus setCallback(
+            const std::shared_ptr<ICameraProviderCallback>& in_callback) override;
+    ndk::ScopedAStatus getVendorTags(std::vector<VendorTagSection>* _aidl_return) override;
+    ndk::ScopedAStatus getCameraIdList(std::vector<std::string>* _aidl_return) override;
+    ndk::ScopedAStatus getCameraDeviceInterface(
+            const std::string& in_cameraDeviceName,
+            std::shared_ptr<ICameraDevice>* _aidl_return) override;
+    ndk::ScopedAStatus notifyDeviceStateChange(int64_t in_deviceState) override;
+    ndk::ScopedAStatus getConcurrentCameraIds(
+            std::vector<ConcurrentCameraIdCombination>* _aidl_return) override;
+    ndk::ScopedAStatus isConcurrentStreamCombinationSupported(
+            const std::vector<CameraIdAndStreamCombination>& in_configs,
+            bool* _aidl_return) override;
+
+  private:
+    void addExternalCamera(const char* devName);
+    void deviceAdded(const char* devName);
+    void deviceRemoved(const char* devName);
+    void updateAttachedCameras();
+
+    // A separate thread to monitor '/dev' directory for '/dev/video*' entries
+    // This thread calls back into ExternalCameraProvider when an actionable change is detected.
+    class HotplugThread : public SimpleThread {
+      public:
+        explicit HotplugThread(ExternalCameraProvider* parent);
+        ~HotplugThread() override;
+
+      protected:
+        bool threadLoop() override;
+
+      private:
+        // Returns true if thread initialization succeeded, and false if thread initialization
+        // failed.
+        bool initialize();
+
+        ExternalCameraProvider* mParent = nullptr;
+        const std::unordered_set<std::string> mInternalDevices;
+
+        bool mIsInitialized = false;
+
+        int mINotifyFD = -1;
+        int mWd = -1;
+
+        // struct to wrap mINotifyFD and poll it with timeout
+        struct pollfd mPollFd = {};
+        char mEventBuf[512] = {0};
+    };
+
+    Mutex mLock;
+    std::shared_ptr<ICameraProviderCallback> mCallback = nullptr;
+    std::unordered_map<std::string, CameraDeviceStatus> mCameraStatusMap;  // camera id -> status
+    const ExternalCameraConfig mCfg;
+    std::shared_ptr<HotplugThread> mHotPlugThread;
+};
+
+}  // namespace implementation
+}  // namespace provider
+}  // namespace camera
+}  // namespace hardware
+}  // namespace android
+
+#endif  // HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
diff --git a/camera/provider/default/OWNERS b/camera/provider/default/OWNERS
new file mode 100644
index 0000000..f48a95c
--- /dev/null
+++ b/camera/provider/default/OWNERS
@@ -0,0 +1 @@
+include platform/frameworks/av:/camera/OWNERS
diff --git a/camera/provider/default/android.hardware.camera.provider-V1-external-service-lazy.rc b/camera/provider/default/android.hardware.camera.provider-V1-external-service-lazy.rc
new file mode 100644
index 0000000..dcdd88c
--- /dev/null
+++ b/camera/provider/default/android.hardware.camera.provider-V1-external-service-lazy.rc
@@ -0,0 +1,10 @@
+service vendor.camera.provider-ext /vendor/bin/hw/android.hardware.camera.provider-V1-external-service-lazy
+    interface aidl android.hardware.camera.provider.ICameraProvider/external/0
+    class hal
+    oneshot
+    disabled
+    user cameraserver
+    group audio camera input drmrpc usb
+    ioprio rt 4
+    capabilities SYS_NICE
+    task_profiles CameraServiceCapacity MaxPerformance
\ No newline at end of file
diff --git a/camera/provider/default/android.hardware.camera.provider-V1-external-service.rc b/camera/provider/default/android.hardware.camera.provider-V1-external-service.rc
new file mode 100644
index 0000000..302c56f
--- /dev/null
+++ b/camera/provider/default/android.hardware.camera.provider-V1-external-service.rc
@@ -0,0 +1,8 @@
+service vendor.camera.provider-ext /vendor/bin/hw/android.hardware.camera.provider-V1-external-service
+    interface aidl android.hardware.camera.provider.ICameraProvider/external/0
+    class hal
+    user cameraserver
+    group audio camera input drmrpc usb
+    ioprio rt 4
+    capabilities SYS_NICE
+    task_profiles CameraServiceCapacity MaxPerformance
\ No newline at end of file
diff --git a/camera/provider/default/external-service.cpp b/camera/provider/default/external-service.cpp
new file mode 100644
index 0000000..b18f182
--- /dev/null
+++ b/camera/provider/default/external-service.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <ExternalCameraProvider.h>
+#include <android-base/logging.h>
+#include <android/binder_manager.h>
+#include <android/binder_process.h>
+
+using ::android::hardware::camera::provider::implementation::ExternalCameraProvider;
+
+namespace {
+// Default recommended RPC thread count for camera provider implementations
+const int HWBINDER_THREAD_COUNT = 6;
+}  // namespace
+
+int main() {
+    ALOGI("CameraProvider: external webcam service is starting.");
+
+    ABinderProcess_setThreadPoolMaxThreadCount(HWBINDER_THREAD_COUNT);
+
+    std::shared_ptr<ExternalCameraProvider> defaultProvider =
+            ndk::SharedRefBase::make<ExternalCameraProvider>();
+    const std::string serviceName = std::string(ExternalCameraProvider::descriptor) + "/external/0";
+
+#ifdef LAZY_SERVICE
+    binder_exception_t ret = AServiceManager_registerLazyService(defaultProvider->asBinder().get(),
+                                                                 serviceName.c_str());
+    LOG_ALWAYS_FATAL_IF(ret != EX_NONE,
+                        "Error while registering lazy ext camera provider service: %d", ret);
+#else
+    binder_exception_t ret =
+            AServiceManager_addService(defaultProvider->asBinder().get(), serviceName.c_str());
+    LOG_ALWAYS_FATAL_IF(ret != EX_NONE, "Error while registering ext camera provider service: %d",
+                        ret);
+#endif
+
+    ABinderProcess_joinThreadPool();
+    return EXIT_FAILURE;  // should not reach
+}
\ No newline at end of file