diff --git a/camera/device/3.4/default/ExternalCameraDevice.cpp b/camera/device/3.4/default/ExternalCameraDevice.cpp
index f518a15..677b496 100644
--- a/camera/device/3.4/default/ExternalCameraDevice.cpp
+++ b/camera/device/3.4/default/ExternalCameraDevice.cpp
@@ -20,6 +20,7 @@
 
 #include <algorithm>
 #include <array>
+#include <regex>
 #include <linux/videodev2.h>
 #include "android-base/macros.h"
 #include "CameraMetadata.h"
@@ -46,10 +47,20 @@
 
 } // anonymous namespace
 
+const std::regex kDevicePathRE("/dev/video([0-9]+)");
+
 ExternalCameraDevice::ExternalCameraDevice(
-        const std::string& cameraId, const ExternalCameraConfig& cfg) :
-        mCameraId(cameraId),
-        mCfg(cfg) {}
+        const std::string& devicePath, const ExternalCameraConfig& cfg) :
+        mCameraId("-1"),
+        mDevicePath(devicePath),
+        mCfg(cfg) {
+    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() {}
 
@@ -129,20 +140,20 @@
         return Void();
     }
 
-    unique_fd fd(::open(mCameraId.c_str(), O_RDWR));
+    unique_fd fd(::open(mDevicePath.c_str(), O_RDWR));
     if (fd.get() < 0) {
         int numAttempt = 0;
         do {
             ALOGW("%s: v4l2 device %s open failed, wait 33ms and try again",
-                    __FUNCTION__, mCameraId.c_str());
+                    __FUNCTION__, mDevicePath.c_str());
             usleep(OPEN_RETRY_SLEEP_US); // sleep and try again
-            fd.reset(::open(mCameraId.c_str(), O_RDWR));
+            fd.reset(::open(mDevicePath.c_str(), O_RDWR));
             numAttempt++;
         } while (fd.get() < 0 && numAttempt <= MAX_RETRY);
 
         if (fd.get() < 0) {
             ALOGE("%s: v4l2 device open %s failed: %s",
-                    __FUNCTION__, mCameraId.c_str(), strerror(errno));
+                    __FUNCTION__, mDevicePath.c_str(), strerror(errno));
             mLock.unlock();
             _hidl_cb(Status::INTERNAL_ERROR, nullptr);
             return Void();
@@ -203,9 +214,9 @@
 status_t ExternalCameraDevice::initCameraCharacteristics() {
     if (mCameraCharacteristics.isEmpty()) {
         // init camera characteristics
-        unique_fd fd(::open(mCameraId.c_str(), O_RDWR));
+        unique_fd fd(::open(mDevicePath.c_str(), O_RDWR));
         if (fd.get() < 0) {
-            ALOGE("%s: v4l2 device open %s failed", __FUNCTION__, mCameraId.c_str());
+            ALOGE("%s: v4l2 device open %s failed", __FUNCTION__, mDevicePath.c_str());
             return DEAD_OBJECT;
         }
 
diff --git a/camera/device/3.4/default/ExternalCameraUtils.cpp b/camera/device/3.4/default/ExternalCameraUtils.cpp
index 62a4c87..8f4626c 100644
--- a/camera/device/3.4/default/ExternalCameraUtils.cpp
+++ b/camera/device/3.4/default/ExternalCameraUtils.cpp
@@ -703,6 +703,7 @@
 namespace common {
 
 namespace {
+    const int kDefaultCameraIdOffset = 100;
     const int kDefaultJpegBufSize = 5 << 20; // 5MB
     const int kDefaultNumVideoBuffer = 4;
     const int kDefaultNumStillBuffer = 2;
@@ -738,6 +739,11 @@
         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__);
@@ -874,6 +880,7 @@
 }
 
 ExternalCameraConfig::ExternalCameraConfig() :
+        cameraIdOffset(kDefaultCameraIdOffset),
         maxJpegBufSize(kDefaultJpegBufSize),
         numVideoBuffers(kDefaultNumVideoBuffer),
         numStillBuffers(kDefaultNumStillBuffer),
diff --git a/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraDevice_3_4.h b/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraDevice_3_4.h
index 1958fcb..88726f4 100644
--- a/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraDevice_3_4.h
+++ b/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraDevice_3_4.h
@@ -149,6 +149,7 @@
     bool mInitialized = false;
     bool mInitFailed = false;
     std::string mCameraId;
+    std::string mDevicePath;
     const ExternalCameraConfig& mCfg;
     std::vector<SupportedV4L2Format> mSupportedFormats;
     CroppingType mCroppingType;
diff --git a/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraUtils.h b/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraUtils.h
index 74f75eb..b354406 100644
--- a/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraUtils.h
+++ b/camera/device/3.4/default/include/ext_device_v3_4_impl/ExternalCameraUtils.h
@@ -68,6 +68,9 @@
     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;
 
diff --git a/camera/provider/2.4/default/ExternalCameraProviderImpl_2_4.cpp b/camera/provider/2.4/default/ExternalCameraProviderImpl_2_4.cpp
index 2bfced2..64a51f6 100644
--- a/camera/provider/2.4/default/ExternalCameraProviderImpl_2_4.cpp
+++ b/camera/provider/2.4/default/ExternalCameraProviderImpl_2_4.cpp
@@ -44,17 +44,19 @@
 const char* kDevicePath = "/dev/";
 constexpr char kPrefix[] = "video";
 constexpr int kPrefixLen = sizeof(kPrefix) - 1;
+constexpr int kDevicePrefixLen = sizeof(kDevicePath) + kPrefixLen + 1;
 
-bool matchDeviceName(const hidl_string& deviceName, std::string* deviceVersion,
-                     std::string* cameraId) {
+bool matchDeviceName(int cameraIdOffset,
+                     const hidl_string& deviceName, std::string* deviceVersion,
+                     std::string* cameraDevicePath) {
     std::string deviceNameStd(deviceName.c_str());
     std::smatch sm;
     if (std::regex_match(deviceNameStd, sm, kDeviceNameRE)) {
         if (deviceVersion != nullptr) {
             *deviceVersion = sm[1];
         }
-        if (cameraId != nullptr) {
-            *cameraId = sm[2];
+        if (cameraDevicePath != nullptr) {
+            *cameraDevicePath = "/dev/video" + std::to_string(std::stoi(sm[2]) - cameraIdOffset);
         }
         return true;
     }
@@ -146,8 +148,9 @@
         const hidl_string& cameraDeviceName,
         ICameraProvider::getCameraDeviceInterface_V3_x_cb _hidl_cb) {
 
-    std::string cameraId, deviceVersion;
-    bool match = matchDeviceName(cameraDeviceName, &deviceVersion, &cameraId);
+    std::string cameraDevicePath, deviceVersion;
+    bool match = matchDeviceName(mCfg.cameraIdOffset, cameraDeviceName,
+                                 &deviceVersion, &cameraDevicePath);
     if (!match) {
         _hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
         return Void();
@@ -164,19 +167,19 @@
         case 4: {
             ALOGV("Constructing v3.4 external camera device");
             deviceImpl = new device::V3_4::implementation::ExternalCameraDevice(
-                    cameraId, mCfg);
+                    cameraDevicePath, mCfg);
             break;
         }
         case 5: {
             ALOGV("Constructing v3.5 external camera device");
             deviceImpl = new device::V3_5::implementation::ExternalCameraDevice(
-                    cameraId, mCfg);
+                    cameraDevicePath, mCfg);
             break;
         }
         case 6: {
             ALOGV("Constructing v3.6 external camera device");
             deviceImpl = new device::V3_6::implementation::ExternalCameraDevice(
-                    cameraId, mCfg);
+                    cameraDevicePath, mCfg);
             break;
         }
         default:
@@ -186,7 +189,7 @@
     }
 
     if (deviceImpl == nullptr || deviceImpl->isInitFailed()) {
-        ALOGE("%s: camera device %s init failed!", __FUNCTION__, cameraId.c_str());
+        ALOGE("%s: camera device %s init failed!", __FUNCTION__, cameraDevicePath.c_str());
         _hidl_cb(Status::INTERNAL_ERROR, nullptr);
         return Void();
     }
@@ -210,12 +213,14 @@
     ALOGI("ExtCam: adding %s to External Camera HAL!", devName);
     Mutex::Autolock _l(mLock);
     std::string deviceName;
+    std::string cameraId = std::to_string(mCfg.cameraIdOffset +
+                                          std::atoi(devName + kDevicePrefixLen));
     if (mPreferredHal3MinorVersion == 6) {
-        deviceName = std::string("device@3.6/external/") + devName;
+        deviceName = std::string("device@3.6/external/") + cameraId;
     } else if (mPreferredHal3MinorVersion == 5) {
-        deviceName = std::string("device@3.5/external/") + devName;
+        deviceName = std::string("device@3.5/external/") + cameraId;
     } else {
-        deviceName = std::string("device@3.4/external/") + devName;
+        deviceName = std::string("device@3.4/external/") + cameraId;
     }
     mCameraStatusMap[deviceName] = CameraDeviceStatus::PRESENT;
     if (mCallbacks != nullptr) {
@@ -259,12 +264,14 @@
 void ExternalCameraProviderImpl_2_4::deviceRemoved(const char* devName) {
     Mutex::Autolock _l(mLock);
     std::string deviceName;
+    std::string cameraId = std::to_string(mCfg.cameraIdOffset +
+                                          std::atoi(devName + kDevicePrefixLen));
     if (mPreferredHal3MinorVersion == 6) {
-        deviceName = std::string("device@3.6/external/") + devName;
+        deviceName = std::string("device@3.6/external/") + cameraId;
     } else if (mPreferredHal3MinorVersion == 5) {
-        deviceName = std::string("device@3.5/external/") + devName;
+        deviceName = std::string("device@3.5/external/") + cameraId;
     } else {
-        deviceName = std::string("device@3.4/external/") + devName;
+        deviceName = std::string("device@3.4/external/") + cameraId;
     }
     if (mCameraStatusMap.find(deviceName) != mCameraStatusMap.end()) {
         mCameraStatusMap.erase(deviceName);