Refactor how padding is calculated.

webrtc/video/vie_encoder.cc

Index: webrtc/video/vie_encoder.cc
diff --git a/webrtc/video/vie_encoder.cc b/webrtc/video/vie_encoder.cc
index d10e8fc5cda67313556eddbcb1cfa48875020394..77eb5d36a60a35d37fd4dfcf09d14534f1e2fd04 100644
--- a/webrtc/video/vie_encoder.cc
+++ b/webrtc/video/vie_encoder.cc
@@ -28,13 +28,11 @@
 
 namespace webrtc {
 
-static const float kStopPaddingThresholdMs = 2000;
-
 ViEEncoder::ViEEncoder(uint32_t number_of_cores,
                        ProcessThread* module_process_thread,
                        SendStatisticsProxy* stats_proxy,
                        OveruseFrameDetector* overuse_detector,
-                       EncodedImageCallback* sink)
+                       VideoEncoderSink* sink)
     : number_of_cores_(number_of_cores),
       sink_(sink),
       vp_(VideoProcessing::Create()),
@@ -43,10 +41,10 @@ ViEEncoder::ViEEncoder(uint32_t number_of_cores,
       overuse_detector_(overuse_detector),
       time_of_last_frame_activity_ms_(0),
       encoder_config_(),
-      min_transmit_bitrate_bps_(0),
       last_observed_bitrate_bps_(0),
       encoder_paused_(true),
       encoder_paused_and_dropped_frame_(false),
+      reported_timeout_(false),
       module_process_thread_(module_process_thread),
       has_received_sli_(false),
       picture_id_sli_(0),
@@ -88,7 +86,6 @@ int32_t ViEEncoder::DeRegisterExternalEncoder(uint8_t pl_type) {
 }
 
 void ViEEncoder::SetEncoder(const webrtc::VideoCodec& video_codec,
-                            int min_transmit_bitrate_bps,
                             size_t max_data_payload_length) {
   // Setting target width and height for VPM.
   RTC_CHECK_EQ(VPM_OK,
@@ -100,7 +97,6 @@ void ViEEncoder::SetEncoder(const webrtc::VideoCodec& video_codec,
   {
     rtc::CritScope lock(&data_cs_);
     encoder_config_ = video_codec;
-    min_transmit_bitrate_bps_ = min_transmit_bitrate_bps;
   }
 
   bool success = video_sender_.RegisterSendCodec(
@@ -129,63 +125,6 @@ void ViEEncoder::SetEncoder(const webrtc::VideoCodec& video_codec,
   }
 }
 
-int ViEEncoder::GetPaddingNeededBps() const {
-  int64_t time_of_last_frame_activity_ms;
-  int min_transmit_bitrate_bps;
-  int bitrate_bps;
-  VideoCodec send_codec;
-  {
-    rtc::CritScope lock(&data_cs_);
-    bool send_padding = encoder_config_.numberOfSimulcastStreams > 1 ||
-                        video_suspended_ || min_transmit_bitrate_bps_ > 0;
-    if (!send_padding)
-      return 0;
-    time_of_last_frame_activity_ms = time_of_last_frame_activity_ms_;
-    min_transmit_bitrate_bps = min_transmit_bitrate_bps_;
-    bitrate_bps = last_observed_bitrate_bps_;
-    send_codec = encoder_config_;
-  }
-
-  bool video_is_suspended = video_sender_.VideoSuspended();
-
-  // Find the max amount of padding we can allow ourselves to send at this
-  // point, based on which streams are currently active and what our current
-  // available bandwidth is.
-  int pad_up_to_bitrate_bps = 0;
-  if (send_codec.numberOfSimulcastStreams == 0) {
-    pad_up_to_bitrate_bps = send_codec.minBitrate * 1000;
-  } else {
-    SimulcastStream* stream_configs = send_codec.simulcastStream;
-    pad_up_to_bitrate_bps =
-        stream_configs[send_codec.numberOfSimulcastStreams - 1].minBitrate *
-        1000;
-    for (int i = 0; i < send_codec.numberOfSimulcastStreams - 1; ++i) {
-      pad_up_to_bitrate_bps += stream_configs[i].targetBitrate * 1000;
-    }
-  }
-
-  // Disable padding if only sending one stream and video isn't suspended and
-  // min-transmit bitrate isn't used (applied later).
-  if (!video_is_suspended && send_codec.numberOfSimulcastStreams <= 1)
-    pad_up_to_bitrate_bps = 0;
-
-  // The amount of padding should decay to zero if no frames are being
-  // captured/encoded unless a min-transmit bitrate is used.
-  int64_t now_ms = rtc::TimeMillis();
-  if (now_ms - time_of_last_frame_activity_ms > kStopPaddingThresholdMs)
-    pad_up_to_bitrate_bps = 0;
-
-  // Pad up to min bitrate.
-  if (pad_up_to_bitrate_bps < min_transmit_bitrate_bps)
-    pad_up_to_bitrate_bps = min_transmit_bitrate_bps;
-
-  // Padding may never exceed bitrate estimate.
-  if (pad_up_to_bitrate_bps > bitrate_bps)
-    pad_up_to_bitrate_bps = bitrate_bps;
-
-  return pad_up_to_bitrate_bps;
-}
-
 bool ViEEncoder::EncoderPaused() const {
   // Pause video if paused by caller or as long as the network is down or the
   // pacer queue has grown too large in buffered mode.
@@ -213,6 +152,7 @@ void ViEEncoder::TraceFrameDropEnd() {
 
 void ViEEncoder::EncodeVideoFrame(const VideoFrame& video_frame) {
   VideoCodecType codec_type;
+  bool do_report_active = false;
   {
     rtc::CritScope lock(&data_cs_);
     time_of_last_frame_activity_ms_ = rtc::TimeMillis();
@@ -221,9 +161,18 @@ void ViEEncoder::EncodeVideoFrame(const VideoFrame& video_frame) {
       return;
     }
     TraceFrameDropEnd();
+    do_report_active = reported_timeout_;
+    reported_timeout_ = false;
     codec_type = encoder_config_.codecType;
   }
 
+  if (do_report_active) {
+    // We have previously reported that the encoder is inactive and we need to
+    // report the state change.
+    LOG(LS_INFO) << "ViEncoder is active.";
+    sink_->OnEncoderActivityChanged(true);
+  }
+
   TRACE_EVENT_ASYNC_STEP0("webrtc", "Video", video_frame.render_time_ms(),
                           "Encode");
   const VideoFrame* frame_to_send = &video_frame;
@@ -264,6 +213,29 @@ void ViEEncoder::SendKeyFrame() {
   video_sender_.IntraFrameRequest(0);
 }
 
+void ViEEncoder::CheckForActivity() {
+  bool do_report_timeout = false;
+  {
+    rtc::CritScope lock(&data_cs_);
+    // TODO(perkj): Refactor this monitoring once we use TaskQueues and use a
+    // timer instead.
+    // This monitoring was previously achieved by that
+    // VieEncoder::GetPaddingBitrate was by Call for each OnBitrateUpdated.
+    int64_t now_ms = rtc::TimeMillis();
+    if (!reported_timeout_ && !EncoderPaused() &&
+        (now_ms - time_of_last_frame_activity_ms_ >
+         VideoEncoderSink::TimeOutMs)) {
+      do_report_timeout = true;
+      reported_timeout_ = true;
+    }
+  }
+
+  if (do_report_timeout) {
+    LOG(LS_INFO) << "ViEncoder timed out.";
+    sink_->OnEncoderActivityChanged(false);
+  }
+}
+
 void ViEEncoder::SetProtectionMethod(bool nack, bool fec) {
   // Set Video Protection for VCM.
   VCMVideoProtection protection_mode;
@@ -333,6 +305,7 @@ void ViEEncoder::OnBitrateUpdated(uint32_t bitrate_bps,
   video_sender_.SetChannelParameters(bitrate_bps, fraction_lost,
                                      round_trip_time_ms);
   bool video_is_suspended = video_sender_.VideoSuspended();
+
   bool video_suspension_changed;
   {
     rtc::CritScope lock(&data_cs_);