diff --git a/media/codec2/hidl/1.0/utils/Android.bp b/media/codec2/hidl/1.0/utils/Android.bp
index 97dde71..b2a5fee 100644
--- a/media/codec2/hidl/1.0/utils/Android.bp
+++ b/media/codec2/hidl/1.0/utils/Android.bp
@@ -1,4 +1,49 @@
 // DO NOT DEPEND ON THIS DIRECTLY
+// use libcodec2-hidl-client-defaults instead
+cc_library {
+    name: "libcodec2_hidl_client@1.0",
+
+    defaults: ["hidl_defaults"],
+
+    srcs: [
+        "ClientBlockHelper.cpp",
+        "types.cpp",
+    ],
+
+    header_libs: [
+        "libcodec2_internal", // private
+    ],
+
+    shared_libs: [
+        "android.hardware.media.bufferpool@2.0",
+        "android.hardware.media.c2@1.0",
+        "libbase",
+        "libcodec2",
+        "libcodec2_vndk",
+        "libcutils",
+        "libgui",
+        "libhidlbase",
+        "liblog",
+        "libstagefright_bufferpool@2.0",
+        "libui",
+        "libutils",
+    ],
+
+    export_include_dirs: [
+        "include",
+    ],
+
+    export_shared_lib_headers: [
+        "android.hardware.media.c2@1.0",
+        "libcodec2",
+        "libgui",
+        "libstagefright_bufferpool@2.0",
+        "libui",
+    ],
+}
+
+
+// DO NOT DEPEND ON THIS DIRECTLY
 // use libcodec2-hidl-defaults instead
 cc_library {
     name: "libcodec2_hidl@1.0",
@@ -33,12 +78,10 @@
         "android.hardware.media.bufferpool@2.0",
         "android.hardware.media.c2@1.0",
         "android.hardware.media.omx@1.0",
-        "android.hidl.safe_union@1.0",
         "libbase",
         "libcodec2",
         "libcodec2_vndk",
         "libcutils",
-        "libgui",
         "libhidlbase",
         "libhidltransport",
         "libhwbinder",
@@ -58,7 +101,6 @@
         "libcodec2",
         "libhidlbase",
         "libstagefright_bufferpool@2.0",
-        "libstagefright_bufferqueue_helper",
         "libui",
     ],
 }
@@ -73,3 +115,14 @@
         "libcodec2_hidl@1.0",
     ],
 }
+
+// public dependency for Codec 2.0 HAL client
+cc_defaults {
+    name: "libcodec2-hidl-client-defaults",
+    defaults: ["libcodec2-impl-defaults"],
+
+    shared_libs: [
+        "android.hardware.media.c2@1.0",
+        "libcodec2_hidl_client@1.0",
+    ],
+}
diff --git a/media/codec2/hidl/1.0/utils/ClientBlockHelper.cpp b/media/codec2/hidl/1.0/utils/ClientBlockHelper.cpp
new file mode 100644
index 0000000..1786c69
--- /dev/null
+++ b/media/codec2/hidl/1.0/utils/ClientBlockHelper.cpp
@@ -0,0 +1,232 @@
+/*
+ * Copyright 2018 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_NDEBUG 0
+#define LOG_TAG "Codec2-block_helper"
+#include <android-base/logging.h>
+
+#include <android/hardware/graphics/bufferqueue/2.0/IGraphicBufferProducer.h>
+#include <codec2/hidl/1.0/ClientBlockHelper.h>
+#include <gui/bufferqueue/2.0/B2HGraphicBufferProducer.h>
+
+#include <C2AllocatorGralloc.h>
+#include <C2BlockInternal.h>
+#include <C2Buffer.h>
+#include <C2PlatformSupport.h>
+
+#include <iomanip>
+
+namespace android {
+namespace hardware {
+namespace media {
+namespace c2 {
+namespace V1_0 {
+namespace utils {
+
+using HGraphicBufferProducer = ::android::hardware::graphics::bufferqueue::
+        V2_0::IGraphicBufferProducer;
+using B2HGraphicBufferProducer = ::android::hardware::graphics::bufferqueue::
+        V2_0::utils::B2HGraphicBufferProducer;
+
+namespace /* unnamed */ {
+
+// Create a GraphicBuffer object from a graphic block.
+sp<GraphicBuffer> createGraphicBuffer(const C2ConstGraphicBlock& block) {
+    uint32_t width;
+    uint32_t height;
+    uint32_t format;
+    uint64_t usage;
+    uint32_t stride;
+    uint32_t generation;
+    uint64_t bqId;
+    int32_t bqSlot;
+    _UnwrapNativeCodec2GrallocMetadata(
+            block.handle(), &width, &height, &format, &usage,
+            &stride, &generation, &bqId, reinterpret_cast<uint32_t*>(&bqSlot));
+    native_handle_t *grallocHandle =
+            UnwrapNativeCodec2GrallocHandle(block.handle());
+    sp<GraphicBuffer> graphicBuffer =
+            new GraphicBuffer(grallocHandle,
+                              GraphicBuffer::CLONE_HANDLE,
+                              width, height, format,
+                              1, usage, stride);
+    native_handle_delete(grallocHandle);
+    return graphicBuffer;
+}
+
+template <typename BlockProcessor>
+void forEachBlock(C2FrameData& frameData,
+                  BlockProcessor process) {
+    for (const std::shared_ptr<C2Buffer>& buffer : frameData.buffers) {
+        if (buffer) {
+            for (const C2ConstGraphicBlock& block :
+                    buffer->data().graphicBlocks()) {
+                process(block);
+            }
+        }
+    }
+}
+
+template <typename BlockProcessor>
+void forEachBlock(const std::list<std::unique_ptr<C2Work>>& workList,
+                  BlockProcessor process,
+                  bool processInput, bool processOutput) {
+    for (const std::unique_ptr<C2Work>& work : workList) {
+        if (!work) {
+            continue;
+        }
+        if (processInput) {
+            forEachBlock(work->input, process);
+        }
+        if (processOutput) {
+            for (const std::unique_ptr<C2Worklet>& worklet : work->worklets) {
+                if (worklet) {
+                    forEachBlock(worklet->output,
+                                 process);
+                }
+            }
+        }
+    }
+}
+
+sp<HGraphicBufferProducer> getHgbp(const sp<IGraphicBufferProducer>& igbp) {
+    sp<HGraphicBufferProducer> hgbp =
+            igbp->getHalInterface<HGraphicBufferProducer>();
+    return hgbp ? hgbp :
+            new B2HGraphicBufferProducer(igbp);
+}
+
+} // unnamed namespace
+
+status_t attachToBufferQueue(const C2ConstGraphicBlock& block,
+                             const sp<IGraphicBufferProducer>& igbp,
+                             uint32_t generation,
+                             int32_t* bqSlot) {
+    if (!igbp) {
+        LOG(WARNING) << "attachToBufferQueue -- null producer.";
+        return NO_INIT;
+    }
+
+    sp<GraphicBuffer> graphicBuffer = createGraphicBuffer(block);
+    graphicBuffer->setGenerationNumber(generation);
+
+    LOG(VERBOSE) << "attachToBufferQueue -- attaching buffer:"
+            << " block dimension " << block.width() << "x"
+                                   << block.height()
+            << ", graphicBuffer dimension " << graphicBuffer->getWidth() << "x"
+                                           << graphicBuffer->getHeight()
+            << std::hex << std::setfill('0')
+            << ", format 0x" << std::setw(8) << graphicBuffer->getPixelFormat()
+            << ", usage 0x" << std::setw(16) << graphicBuffer->getUsage()
+            << std::dec << std::setfill(' ')
+            << ", stride " << graphicBuffer->getStride()
+            << ", generation " << graphicBuffer->getGenerationNumber();
+
+    status_t result = igbp->attachBuffer(bqSlot, graphicBuffer);
+    if (result != OK) {
+        LOG(WARNING) << "attachToBufferQueue -- attachBuffer failed: "
+                        "status = " << result << ".";
+        return result;
+    }
+    LOG(VERBOSE) << "attachToBufferQueue -- attachBuffer returned slot #"
+                 << *bqSlot << ".";
+    return OK;
+}
+
+bool getBufferQueueAssignment(const C2ConstGraphicBlock& block,
+                              uint32_t* generation,
+                              uint64_t* bqId,
+                              int32_t* bqSlot) {
+    return _C2BlockFactory::GetBufferQueueData(
+            _C2BlockFactory::GetGraphicBlockPoolData(block),
+            generation, bqId, bqSlot);
+}
+
+bool holdBufferQueueBlock(const C2ConstGraphicBlock& block,
+                            const sp<IGraphicBufferProducer>& igbp,
+                            uint64_t bqId,
+                            uint32_t generation) {
+    std::shared_ptr<_C2BlockPoolData> data =
+            _C2BlockFactory::GetGraphicBlockPoolData(block);
+    if (!data) {
+        return false;
+    }
+
+    uint32_t oldGeneration;
+    uint64_t oldId;
+    int32_t oldSlot;
+    // If the block is not bufferqueue-based, do nothing.
+    if (!_C2BlockFactory::GetBufferQueueData(
+            data, &oldGeneration, &oldId, &oldSlot) ||
+            (oldId == 0)) {
+        return false;
+    }
+
+    // If the block's bqId is the same as the desired bqId, just hold.
+    if ((oldId == bqId) && (oldGeneration == generation)) {
+        LOG(VERBOSE) << "holdBufferQueueBlock -- import without attaching:"
+                     << " bqId " << oldId
+                     << ", bqSlot " << oldSlot
+                     << ", generation " << generation
+                     << ".";
+        _C2BlockFactory::HoldBlockFromBufferQueue(data, getHgbp(igbp));
+        return true;
+    }
+
+    // Otherwise, attach to the given igbp, which must not be null.
+    if (!igbp) {
+        return false;
+    }
+
+    int32_t bqSlot;
+    status_t result = attachToBufferQueue(block, igbp, generation, &bqSlot);
+
+    if (result != OK) {
+        LOG(ERROR) << "holdBufferQueueBlock -- fail to attach:"
+                   << " target bqId " << bqId
+                   << ", generation " << generation
+                   << ".";
+        return false;
+    }
+
+    LOG(VERBOSE) << "holdBufferQueueBlock -- attached:"
+                 << " bqId " << bqId
+                 << ", bqSlot " << bqSlot
+                 << ", generation " << generation
+                 << ".";
+    _C2BlockFactory::AssignBlockToBufferQueue(
+            data, getHgbp(igbp), generation, bqId, bqSlot, true);
+    return true;
+}
+
+void holdBufferQueueBlocks(const std::list<std::unique_ptr<C2Work>>& workList,
+                           const sp<IGraphicBufferProducer>& igbp,
+                           uint64_t bqId,
+                           uint32_t generation,
+                           bool forInput) {
+    forEachBlock(workList,
+                 std::bind(holdBufferQueueBlock,
+                           std::placeholders::_1, igbp, bqId, generation),
+                 forInput, !forInput);
+}
+
+}  // namespace utils
+}  // namespace V1_0
+}  // namespace c2
+}  // namespace media
+}  // namespace hardware
+}  // namespace android
+
diff --git a/media/codec2/hidl/1.0/utils/ComponentStore.cpp b/media/codec2/hidl/1.0/utils/ComponentStore.cpp
index 53bb6d2..d6f84b4 100644
--- a/media/codec2/hidl/1.0/utils/ComponentStore.cpp
+++ b/media/codec2/hidl/1.0/utils/ComponentStore.cpp
@@ -222,8 +222,7 @@
     sp<InputSurface> inputSurface = new InputSurface(
             this,
             std::make_shared<C2ReflectorHelper>(),
-            new ::android::hardware::graphics::bufferqueue::V2_0::utils::
-                B2HGraphicBufferProducer(source->getIGraphicBufferProducer()),
+            source->getHGraphicBufferProducer(),
             source);
     _hidl_cb(inputSurface ? Status::OK : Status::NO_MEMORY,
              inputSurface);
diff --git a/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/ClientBlockHelper.h b/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/ClientBlockHelper.h
new file mode 100644
index 0000000..be429ac
--- /dev/null
+++ b/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/ClientBlockHelper.h
@@ -0,0 +1,95 @@
+/*
+ * Copyright 2018 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 CLIENT_BLOCK_HELPER_H
+#define CLIENT_BLOCK_HELPER_H
+
+#include <gui/IGraphicBufferProducer.h>
+#include <codec2/hidl/1.0/types.h>
+#include <C2Work.h>
+
+namespace android {
+namespace hardware {
+namespace media {
+namespace c2 {
+namespace V1_0 {
+namespace utils {
+
+
+// BufferQueue-Based Block Operations
+// ==================================
+
+// Create a GraphicBuffer object from a graphic block and attach it to an
+// IGraphicBufferProducer.
+status_t attachToBufferQueue(const C2ConstGraphicBlock& block,
+                             const sp<IGraphicBufferProducer>& igbp,
+                             uint32_t generation,
+                             int32_t* bqSlot);
+
+// Return false if block does not come from a bufferqueue-based blockpool.
+// Otherwise, extract generation, bqId and bqSlot and return true.
+bool getBufferQueueAssignment(const C2ConstGraphicBlock& block,
+                              uint32_t* generation,
+                              uint64_t* bqId,
+                              int32_t* bqSlot);
+
+// Assign the given block to a bufferqueue so that when the block is destroyed,
+// cancelBuffer() will be called.
+//
+// If the block does not come from a bufferqueue-based blockpool, this function
+// returns false.
+//
+// If the block already has a bufferqueue assignment that matches the given one,
+// the function returns true.
+//
+// If the block already has a bufferqueue assignment that does not match the
+// given one, the block will be reassigned to the given bufferqueue. This
+// will call attachBuffer() on the given igbp. The function then returns true on
+// success or false on any failure during the operation.
+//
+// Note: This function should be called after detachBuffer() or dequeueBuffer()
+// is called manually.
+bool holdBufferQueueBlock(const C2ConstGraphicBlock& block,
+                          const sp<IGraphicBufferProducer>& igbp,
+                          uint64_t bqId,
+                          uint32_t generation);
+
+// Call holdBufferQueueBlock() on input or output blocks in the given workList.
+// Since the bufferqueue assignment for input and output buffers can be
+// different, this function takes forInput to determine whether the given
+// bufferqueue is for input buffers or output buffers. (The default value of
+// forInput is false.)
+//
+// In the (rare) case that both input and output buffers are bufferqueue-based,
+// this function must be called twice, once for the input buffers and once for
+// the output buffers.
+//
+// Note: This function should be called after WorkBundle has been received from
+// another process.
+void holdBufferQueueBlocks(const std::list<std::unique_ptr<C2Work>>& workList,
+                           const sp<IGraphicBufferProducer>& igbp,
+                           uint64_t bqId,
+                           uint32_t generation,
+                           bool forInput = false);
+
+}  // namespace utils
+}  // namespace V1_0
+}  // namespace c2
+}  // namespace media
+}  // namespace hardware
+}  // namespace android
+
+#endif  // CLIENT_BLOCK_HELPER_H
diff --git a/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/types.h b/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/types.h
index 817d148..0ddfec5 100644
--- a/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/types.h
+++ b/media/codec2/hidl/1.0/utils/include/codec2/hidl/1.0/types.h
@@ -23,7 +23,6 @@
 #include <android/hardware/media/c2/1.0/IComponentStore.h>
 #include <android/hardware/media/c2/1.0/types.h>
 #include <android/hidl/safe_union/1.0/types.h>
-#include <gui/IGraphicBufferProducer.h>
 
 #include <C2Component.h>
 #include <C2Param.h>
@@ -50,7 +49,6 @@
 using ::android::sp;
 using ::android::hardware::media::bufferpool::V2_0::implementation::
         ConnectionId;
-using ::android::IGraphicBufferProducer;
 
 // Types of metadata for Blocks.
 struct C2Hidl_Range {
@@ -301,20 +299,6 @@
 // BufferQueue-Based Block Operations
 // ==================================
 
-// Create a GraphicBuffer object from a graphic block and attach it to an
-// IGraphicBufferProducer.
-status_t attachToBufferQueue(const C2ConstGraphicBlock& block,
-                             const sp<IGraphicBufferProducer>& igbp,
-                             uint32_t generation,
-                             int32_t* bqSlot);
-
-// Return false if block does not come from a bufferqueue-based blockpool.
-// Otherwise, extract generation, bqId and bqSlot and return true.
-bool getBufferQueueAssignment(const C2ConstGraphicBlock& block,
-                              uint32_t* generation,
-                              uint64_t* bqId,
-                              int32_t* bqSlot);
-
 // Disassociate the given block with its designated bufferqueue so that
 // cancelBuffer() will not be called when the block is destroyed. If the block
 // does not have a designated bufferqueue, the function returns false.
@@ -336,45 +320,6 @@
                             bool processInput = false,
                             bool processOutput = true);
 
-// Assign the given block to a bufferqueue so that when the block is destroyed,
-// cancelBuffer() will be called.
-//
-// If the block does not come from a bufferqueue-based blockpool, this function
-// returns false.
-//
-// If the block already has a bufferqueue assignment that matches the given one,
-// the function returns true.
-//
-// If the block already has a bufferqueue assignment that does not match the
-// given one, the block will be reassigned to the given bufferqueue. This
-// will call attachBuffer() on the given igbp. The function then returns true on
-// success or false on any failure during the operation.
-//
-// Note: This function should be called after detachBuffer() or dequeueBuffer()
-// is called manually.
-bool holdBufferQueueBlock(const C2ConstGraphicBlock& block,
-                          const sp<IGraphicBufferProducer>& igbp,
-                          uint64_t bqId,
-                          uint32_t generation);
-
-// Call holdBufferQueueBlock() on input or output blocks in the given workList.
-// Since the bufferqueue assignment for input and output buffers can be
-// different, this function takes forInput to determine whether the given
-// bufferqueue is for input buffers or output buffers. (The default value of
-// forInput is false.)
-//
-// In the (rare) case that both input and output buffers are bufferqueue-based,
-// this function must be called twice, once for the input buffers and once for
-// the output buffers.
-//
-// Note: This function should be called after WorkBundle has been received from
-// another process.
-void holdBufferQueueBlocks(const std::list<std::unique_ptr<C2Work>>& workList,
-                           const sp<IGraphicBufferProducer>& igbp,
-                           uint64_t bqId,
-                           uint32_t generation,
-                           bool forInput = false);
-
 }  // namespace utils
 }  // namespace V1_0
 }  // namespace c2
diff --git a/media/codec2/hidl/1.0/utils/types.cpp b/media/codec2/hidl/1.0/utils/types.cpp
index 74320e7..3fd2f92 100644
--- a/media/codec2/hidl/1.0/utils/types.cpp
+++ b/media/codec2/hidl/1.0/utils/types.cpp
@@ -18,9 +18,7 @@
 #define LOG_TAG "Codec2-types"
 #include <android-base/logging.h>
 
-#include <android/hardware/graphics/bufferqueue/2.0/IGraphicBufferProducer.h>
 #include <codec2/hidl/1.0/types.h>
-#include <gui/bufferqueue/2.0/B2HGraphicBufferProducer.h>
 #include <media/stagefright/foundation/AUtils.h>
 
 #include <C2AllocatorIon.h>
@@ -54,10 +52,6 @@
         ClientManager;
 using ::android::hardware::media::bufferpool::V2_0::implementation::
         TransactionId;
-using HGraphicBufferProducer = ::android::hardware::graphics::bufferqueue::
-        V2_0::IGraphicBufferProducer;
-using B2HGraphicBufferProducer = ::android::hardware::graphics::bufferqueue::
-        V2_0::utils::B2HGraphicBufferProducer;
 
 const char* asString(Status status, const char* def) {
     return asString(static_cast<c2_status_t>(status), def);
@@ -1741,30 +1735,6 @@
 
 namespace /* unnamed */ {
 
-// Create a GraphicBuffer object from a graphic block.
-sp<GraphicBuffer> createGraphicBuffer(const C2ConstGraphicBlock& block) {
-    uint32_t width;
-    uint32_t height;
-    uint32_t format;
-    uint64_t usage;
-    uint32_t stride;
-    uint32_t generation;
-    uint64_t bqId;
-    int32_t bqSlot;
-    _UnwrapNativeCodec2GrallocMetadata(
-            block.handle(), &width, &height, &format, &usage,
-            &stride, &generation, &bqId, reinterpret_cast<uint32_t*>(&bqSlot));
-    native_handle_t *grallocHandle =
-            UnwrapNativeCodec2GrallocHandle(block.handle());
-    sp<GraphicBuffer> graphicBuffer =
-            new GraphicBuffer(grallocHandle,
-                              GraphicBuffer::CLONE_HANDLE,
-                              width, height, format,
-                              1, usage, stride);
-    native_handle_delete(grallocHandle);
-    return graphicBuffer;
-}
-
 template <typename BlockProcessor>
 void forEachBlock(C2FrameData& frameData,
                   BlockProcessor process) {
@@ -1800,59 +1770,8 @@
     }
 }
 
-sp<HGraphicBufferProducer> getHgbp(const sp<IGraphicBufferProducer>& igbp) {
-    sp<HGraphicBufferProducer> hgbp =
-            igbp->getHalInterface<HGraphicBufferProducer>();
-    return hgbp ? hgbp :
-            new B2HGraphicBufferProducer(igbp);
-}
-
 } // unnamed namespace
 
-status_t attachToBufferQueue(const C2ConstGraphicBlock& block,
-                             const sp<IGraphicBufferProducer>& igbp,
-                             uint32_t generation,
-                             int32_t* bqSlot) {
-    if (!igbp) {
-        LOG(WARNING) << "attachToBufferQueue -- null producer.";
-        return NO_INIT;
-    }
-
-    sp<GraphicBuffer> graphicBuffer = createGraphicBuffer(block);
-    graphicBuffer->setGenerationNumber(generation);
-
-    LOG(VERBOSE) << "attachToBufferQueue -- attaching buffer:"
-            << " block dimension " << block.width() << "x"
-                                   << block.height()
-            << ", graphicBuffer dimension " << graphicBuffer->getWidth() << "x"
-                                           << graphicBuffer->getHeight()
-            << std::hex << std::setfill('0')
-            << ", format 0x" << std::setw(8) << graphicBuffer->getPixelFormat()
-            << ", usage 0x" << std::setw(16) << graphicBuffer->getUsage()
-            << std::dec << std::setfill(' ')
-            << ", stride " << graphicBuffer->getStride()
-            << ", generation " << graphicBuffer->getGenerationNumber();
-
-    status_t result = igbp->attachBuffer(bqSlot, graphicBuffer);
-    if (result != OK) {
-        LOG(WARNING) << "attachToBufferQueue -- attachBuffer failed: "
-                        "status = " << result << ".";
-        return result;
-    }
-    LOG(VERBOSE) << "attachToBufferQueue -- attachBuffer returned slot #"
-                 << *bqSlot << ".";
-    return OK;
-}
-
-bool getBufferQueueAssignment(const C2ConstGraphicBlock& block,
-                              uint32_t* generation,
-                              uint64_t* bqId,
-                              int32_t* bqSlot) {
-    return _C2BlockFactory::GetBufferQueueData(
-            _C2BlockFactory::GetGraphicBlockPoolData(block),
-            generation, bqId, bqSlot);
-}
-
 bool yieldBufferQueueBlock(const C2ConstGraphicBlock& block) {
     std::shared_ptr<_C2BlockPoolData> data =
             _C2BlockFactory::GetGraphicBlockPoolData(block);
@@ -1869,74 +1788,6 @@
     forEachBlock(workList, yieldBufferQueueBlock, processInput, processOutput);
 }
 
-bool holdBufferQueueBlock(const C2ConstGraphicBlock& block,
-                            const sp<IGraphicBufferProducer>& igbp,
-                            uint64_t bqId,
-                            uint32_t generation) {
-    std::shared_ptr<_C2BlockPoolData> data =
-            _C2BlockFactory::GetGraphicBlockPoolData(block);
-    if (!data) {
-        return false;
-    }
-
-    uint32_t oldGeneration;
-    uint64_t oldId;
-    int32_t oldSlot;
-    // If the block is not bufferqueue-based, do nothing.
-    if (!_C2BlockFactory::GetBufferQueueData(
-            data, &oldGeneration, &oldId, &oldSlot) ||
-            (oldId == 0)) {
-        return false;
-    }
-
-    // If the block's bqId is the same as the desired bqId, just hold.
-    if ((oldId == bqId) && (oldGeneration == generation)) {
-        LOG(VERBOSE) << "holdBufferQueueBlock -- import without attaching:"
-                     << " bqId " << oldId
-                     << ", bqSlot " << oldSlot
-                     << ", generation " << generation
-                     << ".";
-        _C2BlockFactory::HoldBlockFromBufferQueue(data, getHgbp(igbp));
-        return true;
-    }
-
-    // Otherwise, attach to the given igbp, which must not be null.
-    if (!igbp) {
-        return false;
-    }
-
-    int32_t bqSlot;
-    status_t result = attachToBufferQueue(block, igbp, generation, &bqSlot);
-
-    if (result != OK) {
-        LOG(ERROR) << "holdBufferQueueBlock -- fail to attach:"
-                   << " target bqId " << bqId
-                   << ", generation " << generation
-                   << ".";
-        return false;
-    }
-
-    LOG(VERBOSE) << "holdBufferQueueBlock -- attached:"
-                 << " bqId " << bqId
-                 << ", bqSlot " << bqSlot
-                 << ", generation " << generation
-                 << ".";
-    _C2BlockFactory::AssignBlockToBufferQueue(
-            data, getHgbp(igbp), generation, bqId, bqSlot, true);
-    return true;
-}
-
-void holdBufferQueueBlocks(const std::list<std::unique_ptr<C2Work>>& workList,
-                           const sp<IGraphicBufferProducer>& igbp,
-                           uint64_t bqId,
-                           uint32_t generation,
-                           bool forInput) {
-    forEachBlock(workList,
-                 std::bind(holdBufferQueueBlock,
-                           std::placeholders::_1, igbp, bqId, generation),
-                 forInput, !forInput);
-}
-
 }  // namespace utils
 }  // namespace V1_0
 }  // namespace c2
diff --git a/media/codec2/hidl/1.0/vts/functional/common/Android.bp b/media/codec2/hidl/1.0/vts/functional/common/Android.bp
index 94f46ed..da0061a 100644
--- a/media/codec2/hidl/1.0/vts/functional/common/Android.bp
+++ b/media/codec2/hidl/1.0/vts/functional/common/Android.bp
@@ -2,7 +2,7 @@
     name: "VtsMediaC2V1_0CommonUtil",
     defaults: [
         "VtsHalTargetTestDefaults",
-        "libcodec2-hidl-defaults",
+        "libcodec2-hidl-client-defaults",
     ],
 
     include_dirs: [
@@ -20,7 +20,7 @@
     name: "VtsMediaC2V1_0Defaults",
     defaults: [
         "VtsHalTargetTestDefaults",
-        "libcodec2-hidl-defaults",
+        "libcodec2-hidl-client-defaults",
     ],
 
     static_libs: [
diff --git a/media/codec2/hidl/client/Android.bp b/media/codec2/hidl/client/Android.bp
index 965e438..a174008 100644
--- a/media/codec2/hidl/client/Android.bp
+++ b/media/codec2/hidl/client/Android.bp
@@ -12,7 +12,7 @@
         "libbase",
         "libbinder",
         "libcodec2",
-        "libcodec2_hidl@1.0",
+        "libcodec2_hidl_client@1.0",
         "libcodec2_vndk",
         "libcutils",
         "libgui",
@@ -30,7 +30,7 @@
 
     export_shared_lib_headers: [
         "libcodec2",
-        "libcodec2_hidl@1.0",
+        "libcodec2_hidl_client@1.0",
     ],
 
 }
diff --git a/media/codec2/hidl/client/include/codec2/hidl/client.h b/media/codec2/hidl/client/include/codec2/hidl/client.h
index 8265380..1851752 100644
--- a/media/codec2/hidl/client/include/codec2/hidl/client.h
+++ b/media/codec2/hidl/client/include/codec2/hidl/client.h
@@ -18,8 +18,7 @@
 #define CODEC2_HIDL_CLIENT_H
 
 #include <gui/IGraphicBufferProducer.h>
-#include <codec2/hidl/1.0/types.h>
-
+#include <codec2/hidl/1.0/ClientBlockHelper.h>
 #include <C2PlatformSupport.h>
 #include <C2Component.h>
 #include <C2Buffer.h>