Refactor how padding is calculated.

webrtc/video/vie_encoder.h

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 31 matching lines @@
 // VieEncoder represent a video encoder that accepts raw video frames as input
 // and produces an encoded bit stream.
 // Usage:
 // 1. Instantiate
 // 2. Call Init
 // 3. Call RegisterExternalEncoder if available.
 // 4. Call SetEncoder with the codec settings and the object that shall receive
 //    the encoded bit stream.
 // 5. Call Start.
 // 6. For each available raw video frame call EncodeVideoFrame.
+
+class VideoEncoderSink : public EncodedImageCallback {
+ public:
+  static const int TimeOutMs = 2000;
+
+  // Triggered if the encoder has not produced a frame for |TimeOutMs|.
+  // The effect of this call is that no padding will be sent for this stream and
+  // thus, this method should thus not be called if padding is needed.
+  // Note that this method should not be called if the encoder is
+  // not supposed to produce data. Ie, the current allowed bitrate is zero.
+  // May be called on an arbitrary thread.
+  virtual void OnEncoderActivityChanged(bool running) = 0;
+
+ protected:
+  virtual ~VideoEncoderSink() {}
+};
+
 class ViEEncoder : public VideoEncoderRateObserver,
                    public EncodedImageCallback,
                    public VCMSendStatisticsCallback {
  public:
   friend class ViEBitrateObserver;
 
   ViEEncoder(uint32_t number_of_cores,
              ProcessThread* module_process_thread,
              SendStatisticsProxy* stats_proxy,
              OveruseFrameDetector* overuse_detector,
-             EncodedImageCallback* sink);
-
+             VideoEncoderSink* sink);
   ~ViEEncoder();
 
   vcm::VideoSender* video_sender();
 
   // Returns the id of the owning channel.
   int Owner() const;
 
   void Start();
   // Drops incoming packets before they get to the encoder.
   void Pause();
 
   // Codec settings.
   int32_t RegisterExternalEncoder(VideoEncoder* encoder,
                                   uint8_t pl_type,
                                   bool internal_source);
   int32_t DeRegisterExternalEncoder(uint8_t pl_type);
   void SetEncoder(const VideoCodec& video_codec,
-                  int min_transmit_bitrate_bps,
                   size_t max_data_payload_length);
 
   void EncodeVideoFrame(const VideoFrame& video_frame);
   void SendKeyFrame();
 
+  // Checks to see if the encoder has produced anything during the last
+  // VideoEncoderSink::TimeOutMs period and if the state has changed, calls
+  // VideoEncoderSink::OnEncoderActivityChanged.
+  // Must be called periodically.
+  // TODO(perkj): CheckForActivity should be replaced with an internal timer
+  // once ViEncoder owns the encoder thread.
+  void CheckForActivity();
+
   uint32_t LastObservedBitrateBps() const;
   // Loss protection. Must be called before SetEncoder() to have max packet size
   // updated according to protection.
   // TODO(pbos): Set protection method on construction.
   void SetProtectionMethod(bool nack, bool fec);
 
   // Implements VideoEncoderRateObserver.
   void OnSetRates(uint32_t bitrate_bps, int framerate) override;
 
   // Implements EncodedImageCallback.
   int32_t Encoded(const EncodedImage& encoded_image,
                   const CodecSpecificInfo* codec_specific_info,
                   const RTPFragmentationHeader* fragmentation) override;
 
   // Implements VideoSendStatisticsCallback.
   void SendStatistics(uint32_t bit_rate,
                       uint32_t frame_rate,
                       const std::string& encoder_name) override;
 
   // virtual to test EncoderStateFeedback with mocks.
   virtual void OnReceivedIntraFrameRequest(size_t stream_index);
   virtual void OnReceivedSLI(uint8_t picture_id);
   virtual void OnReceivedRPSI(uint64_t picture_id);
 
-  int GetPaddingNeededBps() const;
-
   void OnBitrateUpdated(uint32_t bitrate_bps,
                         uint8_t fraction_lost,
                         int64_t round_trip_time_ms);
 
  private:
   bool EncoderPaused() const EXCLUSIVE_LOCKS_REQUIRED(data_cs_);
   void TraceFrameDropStart() EXCLUSIVE_LOCKS_REQUIRED(data_cs_);
   void TraceFrameDropEnd() EXCLUSIVE_LOCKS_REQUIRED(data_cs_);
 
   const uint32_t number_of_cores_;
-  EncodedImageCallback* const sink_;
+  VideoEncoderSink* const sink_;
 
   const std::unique_ptr<VideoProcessing> vp_;
   vcm::VideoSender video_sender_;
 
   rtc::CriticalSection data_cs_;
 
   SendStatisticsProxy* const stats_proxy_;
   OveruseFrameDetector* const overuse_detector_;
 
   // The time we last received an input frame or encoded frame. This is used to
   // track when video is stopped long enough that we also want to stop sending
   // padding.
   int64_t time_of_last_frame_activity_ms_ GUARDED_BY(data_cs_);
   VideoCodec encoder_config_ GUARDED_BY(data_cs_);
-  int min_transmit_bitrate_bps_ GUARDED_BY(data_cs_);
   uint32_t last_observed_bitrate_bps_ GUARDED_BY(data_cs_);
   bool encoder_paused_ GUARDED_BY(data_cs_);
   bool encoder_paused_and_dropped_frame_ GUARDED_BY(data_cs_);
+  bool reported_timeout_ GUARDED_BY(data_cs_);
 
   ProcessThread* module_process_thread_;
 
   bool has_received_sli_ GUARDED_BY(data_cs_);
   uint8_t picture_id_sli_ GUARDED_BY(data_cs_);
   bool has_received_rpsi_ GUARDED_BY(data_cs_);
   uint64_t picture_id_rpsi_ GUARDED_BY(data_cs_);
 
   bool video_suspended_ GUARDED_BY(data_cs_);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_VIDEO_VIE_ENCODER_H_