Start the video stream using the parameters from the allocated stream

Author: yufengwangca

examples/camera-app/camera-common/include/camera-device-interface.h

@@ -166,7 +166,7 @@ class CameraDeviceInterface
         virtual CameraError CaptureSnapshot(const chip::app::DataModel::Nullable<uint16_t> streamID,
                                             const VideoResolutionStruct & resolution, ImageSnapshot & outImageSnapshot) = 0;
         // Start video stream
-        virtual CameraError StartVideoStream(uint16_t streamID) = 0;
+        virtual CameraError StartVideoStream(const VideoStreamStruct & allocatedStream) = 0;
 
         // Stop video stream
         virtual CameraError StopVideoStream(uint16_t streamID) = 0;

examples/camera-app/linux/include/camera-device.h

@@ -107,7 +107,7 @@ class CameraDevice : public CameraDeviceInterface, public CameraDeviceInterface:
     CameraError CaptureSnapshot(const chip::app::DataModel::Nullable<uint16_t> streamID, const VideoResolutionStruct & resolution,
                                 ImageSnapshot & outImageSnapshot) override;
 
-    CameraError StartVideoStream(uint16_t streamID) override;
+    CameraError StartVideoStream(const VideoStreamStruct & allocatedStream) override;
 
     // Stop video stream
     CameraError StopVideoStream(uint16_t streamID) override;

examples/camera-app/linux/include/clusters/camera-avstream-mgmt/camera-av-stream-manager.h

@@ -55,6 +55,8 @@ class CameraAVStreamManager : public CameraAVStreamMgmtDelegate, public CameraAV
 
     Protocols::InteractionModel::Status SnapshotStreamDeallocate(const uint16_t streamID) override;
 
+    void OnVideoStreamAllocated(const VideoStreamStruct & allocatedStream) override;
+
     void OnStreamUsagePrioritiesChanged() override;
 
     void OnAttributeChanged(AttributeId attributeId) override;

examples/camera-app/linux/src/camera-device.cpp

@@ -624,21 +624,21 @@ CameraError CameraDevice::CaptureSnapshot(const chip::app::DataModel::Nullable<u
     return CameraError::SUCCESS;
 }
 
-CameraError CameraDevice::StartVideoStream(uint16_t streamID)
+CameraError CameraDevice::StartVideoStream(const VideoStreamStruct & allocatedStream)
 {
-    auto it = std::find_if(mVideoStreams.begin(), mVideoStreams.end(),
-                           [streamID](const VideoStream & s) { return s.videoStreamParams.videoStreamID == streamID; });
+    uint16_t streamID = allocatedStream.videoStreamID;
+    auto it           = std::find_if(mVideoStreams.begin(), mVideoStreams.end(),
+                                     [streamID](const VideoStream & s) { return s.videoStreamParams.videoStreamID == streamID; });
 
     if (it == mVideoStreams.end())
     {
         return CameraError::ERROR_VIDEO_STREAM_START_FAILED;
     }
 
-    // Create Gstreamer video pipeline
-    CameraError error = CameraError::SUCCESS;
-    GstElement * videoPipeline =
-        CreateVideoPipeline(mVideoDevicePath, it->videoStreamParams.minResolution.width, it->videoStreamParams.minResolution.height,
-                            it->videoStreamParams.minFrameRate, error);
+    // Create Gstreamer video pipeline using the final allocated stream parameters
+    CameraError error          = CameraError::SUCCESS;
+    GstElement * videoPipeline = CreateVideoPipeline(mVideoDevicePath, allocatedStream.minResolution.width,
+                                                     allocatedStream.minResolution.height, allocatedStream.minFrameRate, error);
     if (videoPipeline == nullptr)
     {
         ChipLogError(Camera, "Failed to create video pipeline.");
@@ -656,8 +656,9 @@ CameraError CameraDevice::StartVideoStream(uint16_t streamID)
         gst_object_unref(appsink);
     }
 
-    ChipLogProgress(Camera, "Starting video stream (id=%u): %u×%u @ %ufps", streamID, it->videoStreamParams.minResolution.width,
-                    it->videoStreamParams.minResolution.height, it->videoStreamParams.minFrameRate);
+    ChipLogProgress(Camera, "Starting video stream (id=%u): %u×%u @ %ufps", streamID, allocatedStream.maxResolution.width,
+    ChipLogProgress(Camera, "Starting video stream (id=%u): %u×%u @ %ufps", streamID, allocatedStream.minResolution.width,
+                    allocatedStream.minResolution.height, allocatedStream.minFrameRate);
 
     // Start the pipeline
     ChipLogProgress(Camera, "Requesting PLAYING …");

examples/camera-app/linux/src/clusters/camera-avstream-mgmt/camera-av-stream-manager.cpp

@@ -127,20 +127,13 @@ Protocols::InteractionModel::Status CameraAVStreamManager::VideoStreamAllocate(c
             if (!stream.isAllocated)
             {
                 stream.isAllocated = true;
-
-                // Start the video stream from HAL for serving.
-                mCameraDeviceHAL->GetCameraHALInterface().StartVideoStream(outStreamID);
-
                 // Set the default viewport on the newly allocated stream
                 mCameraDeviceHAL->GetCameraHALInterface().SetViewport(stream,
                                                                       mCameraDeviceHAL->GetCameraHALInterface().GetViewport());
 
                 // Inform DPTZ that there's an allocated stream
                 mCameraDeviceHAL->GetCameraAVSettingsUserLevelMgmtDelegate().VideoStreamAllocated(outStreamID);
 
-                // Set the current frame rate attribute from HAL once stream has started
-                GetCameraAVStreamMgmtServer()->SetCurrentFrameRate(mCameraDeviceHAL->GetCameraHALInterface().GetCurrentFrameRate());
-
                 return Status::Success;
             }
             else
@@ -155,6 +148,15 @@ Protocols::InteractionModel::Status CameraAVStreamManager::VideoStreamAllocate(c
     return Status::DynamicConstraintError;
 }
 
+void CameraAVStreamManager::OnVideoStreamAllocated(const VideoStreamStruct & allocatedStream)
+{
+    // Start the video stream using the final allocated parameters
+    mCameraDeviceHAL->GetCameraHALInterface().StartVideoStream(allocatedStream);
+
+    // Set the current frame rate attribute from HAL once stream has started
+    GetCameraAVStreamMgmtServer()->SetCurrentFrameRate(mCameraDeviceHAL->GetCameraHALInterface().GetCurrentFrameRate());
+}
+
 Protocols::InteractionModel::Status CameraAVStreamManager::VideoStreamModify(const uint16_t streamID,
                                                                              const chip::Optional<bool> waterMarkEnabled,
                                                                              const chip::Optional<bool> osdEnabled)

src/app/clusters/camera-av-stream-management-server/camera-av-stream-management-server.cpp

@@ -1804,6 +1804,9 @@ void CameraAVStreamMgmtServer::HandleVideoStreamAllocate(HandlerContext & ctx,
 
         response.videoStreamID = videoStreamID;
         ctx.mCommandHandler.AddResponse(ctx.mRequestPath, response);
+
+        // Call delegate with the final allocated stream parameters
+        mDelegate.OnVideoStreamAllocated(videoStreamArgs);
     }
     else
     {

src/app/clusters/camera-av-stream-management-server/camera-av-stream-management-server.h

@@ -107,6 +107,14 @@ class CameraAVStreamMgmtDelegate
     virtual Protocols::InteractionModel::Status VideoStreamAllocate(const VideoStreamStruct & allocateArgs,
                                                                     uint16_t & outStreamID) = 0;
 
+    /**
+     *   @brief Called after the server has finalized video stream allocation and narrowed parameters.
+     *          This is where the actual video stream should be started using the final allocated parameters.
+     *
+     *   @param allocatedStream   The finalized video stream with narrowed parameters from the server.
+     */
+    virtual void OnVideoStreamAllocated(const VideoStreamStruct & allocatedStream) = 0;
+
     /**
      *   @brief Handle Command Delegate for Video stream modification.
      *