Deliver video frames on Android, on the decode thread.
VideoCoding
* Adding a method for polling for frames on Android only until the capture implementation takes care of this (longer term plan).
CodecDatabase
* Add an accessor for the current decoder
* Use std::unique_ptr<> for ownership.
* Remove "Release()" and "ReleaseDecoder()". Instead just delete.
* Remove |friend| relationship between CodecDatabase and VCMGenericDecoder.
VCMDecodedFrameCallback
* DCHECKs for thread correctness.
* Remove |lock_| now that a threading model has been established and verified.
VCMGenericDecoder
* All methods now have thread checks.
* Variable access associated with thread checkers.
VideoReceiver
* Added two notification methods, DecoderThreadStarting() and DecoderThreadStopped()
* Allows us to establish a period when the decoder thread is not running and it is safe to modify variables such as callbacks, that are only read when the decoder thread is running.
* Allows us to DCHECK thread guarantees.
* Allows synchronizing callbacks from the module process thread and have them only active while the decoder thread is running.
* The above, allows us to establish two modes for the thread, single-threaded-mutable and multi-threaded-const.
* Using that knowledge, we can remove |receive_crit_| as well as locking for a number of member variables.
MediaCodecVideoDecoder
* Removed frame polling code from this class, since this is now done from the root thread function in VideoReceiveStream.
VideoReceiveStream
* On Android: Polls for decoded frames every 10ms (same interval as previously in MediaCodecVideoDecoder)
* [Un]Registers the |video_receiver_| with the module thread only around the time the decoder thread is started/stopped.
* Notifies the receiver of start/stop events of the decoder thread.
* Changed the decoder thread to use the new PlatformThread callback type.
BUG=webrtc:7361, 695438
Review-Url: https://codereview.webrtc.org/2764573002
Cr-Commit-Position: refs/heads/master@{#17527}
diff --git a/webrtc/modules/video_coding/video_coding_impl.h b/webrtc/modules/video_coding/video_coding_impl.h
index 5e547df..d6e722d 100644
--- a/webrtc/modules/video_coding/video_coding_impl.h
+++ b/webrtc/modules/video_coding/video_coding_impl.h
@@ -35,6 +35,7 @@
namespace webrtc {
+class ProcessThread;
class VideoBitrateAllocator;
class VideoBitrateAllocationObserver;
@@ -150,7 +151,7 @@
VCMTiming* timing,
NackSender* nack_sender = nullptr,
KeyFrameRequestSender* keyframe_request_sender = nullptr);
- ~VideoReceiver();
+ ~VideoReceiver() override;
int32_t RegisterReceiveCodec(const VideoCodec* receiveCodec,
int32_t numberOfCores,
@@ -168,8 +169,10 @@
int32_t Decode(const webrtc::VCMEncodedFrame* frame);
- // Called on the decoder thread when thread is exiting.
- void DecodingStopped();
+#if defined(WEBRTC_ANDROID)
+ // See https://bugs.chromium.org/p/webrtc/issues/detail?id=7361
+ void PollDecodedFrames();
+#endif
int32_t IncomingPacket(const uint8_t* incomingPayload,
size_t payloadLength,
@@ -195,39 +198,66 @@
int64_t TimeUntilNextProcess() override;
void Process() override;
+ void ProcessThreadAttached(ProcessThread* process_thread) override;
void TriggerDecoderShutdown();
+ void DecoderThreadStarting();
+ void DecoderThreadStopped();
protected:
- int32_t Decode(const webrtc::VCMEncodedFrame& frame)
- EXCLUSIVE_LOCKS_REQUIRED(receive_crit_);
+ int32_t Decode(const webrtc::VCMEncodedFrame& frame);
int32_t RequestKeyFrame();
private:
+ // Used for DCHECKing thread correctness.
+ // In build where DCHECKs are enabled, will return false before
+ // DecoderThreadStarting is called, then true until DecoderThreadStopped
+ // is called.
+ // In builds where DCHECKs aren't enabled, it will return true.
+ bool IsDecoderThreadRunning();
+
rtc::ThreadChecker construction_thread_;
+ rtc::ThreadChecker decoder_thread_;
+ rtc::ThreadChecker module_thread_;
Clock* const clock_;
rtc::CriticalSection process_crit_;
- rtc::CriticalSection receive_crit_;
VCMTiming* _timing;
VCMReceiver _receiver;
VCMDecodedFrameCallback _decodedFrameCallback;
- VCMFrameTypeCallback* _frameTypeCallback GUARDED_BY(process_crit_);
- VCMReceiveStatisticsCallback* _receiveStatsCallback GUARDED_BY(process_crit_);
- VCMPacketRequestCallback* _packetRequestCallback GUARDED_BY(process_crit_);
- VCMFrameBuffer _frameFromFile;
+ // These callbacks are set on the construction thread before being attached
+ // to the module thread or decoding started, so a lock is not required.
+ VCMFrameTypeCallback* _frameTypeCallback;
+ VCMReceiveStatisticsCallback* _receiveStatsCallback;
+ VCMPacketRequestCallback* _packetRequestCallback;
+
+ // Used on both the module and decoder thread.
bool _scheduleKeyRequest GUARDED_BY(process_crit_);
bool drop_frames_until_keyframe_ GUARDED_BY(process_crit_);
- size_t max_nack_list_size_ GUARDED_BY(process_crit_);
- VCMCodecDataBase _codecDataBase GUARDED_BY(receive_crit_);
- EncodedImageCallback* pre_decode_image_callback_;
+ // Modified on the construction thread while not attached to the process
+ // thread. Once attached to the process thread, its value is only read
+ // so a lock is not required.
+ size_t max_nack_list_size_;
- VCMProcessTimer _receiveStatsTimer;
- VCMProcessTimer _retransmissionTimer;
- VCMProcessTimer _keyRequestTimer;
- QpParser qp_parser_;
- ThreadUnsafeOneTimeEvent first_frame_received_;
+ // Callbacks are set before the decoder thread starts.
+ // Once the decoder thread has been started, usage of |_codecDataBase| moves
+ // over to the decoder thread.
+ VCMCodecDataBase _codecDataBase;
+ EncodedImageCallback* const pre_decode_image_callback_;
+
+ VCMProcessTimer _receiveStatsTimer ACCESS_ON(module_thread_);
+ VCMProcessTimer _retransmissionTimer ACCESS_ON(module_thread_);
+ VCMProcessTimer _keyRequestTimer ACCESS_ON(module_thread_);
+ QpParser qp_parser_ ACCESS_ON(decoder_thread_);
+ ThreadUnsafeOneTimeEvent first_frame_received_ ACCESS_ON(decoder_thread_);
+ // Modified on the construction thread. Can be read without a lock and assumed
+ // to be non-null on the module and decoder threads.
+ ProcessThread* process_thread_ = nullptr;
+ bool is_attached_to_process_thread_ ACCESS_ON(construction_thread_) = false;
+#if RTC_DCHECK_IS_ON
+ bool decoder_thread_is_running_ = false;
+#endif
};
} // namespace vcm