[Video] Disable bg optimization if avg keyframe distance is >10s

media/filters/decoder_stream_traits.cc

Index: media/filters/decoder_stream_traits.cc
diff --git a/media/filters/decoder_stream_traits.cc b/media/filters/decoder_stream_traits.cc
index fcbc19e4baa8e7f680afb3b22f3caa0d6842a03c..0edc6f2d1d06f66133f73fc78c8b74105ae44826 100644
--- a/media/filters/decoder_stream_traits.cc
+++ b/media/filters/decoder_stream_traits.cc
@@ -28,15 +28,6 @@ bool DecoderStreamTraits<DemuxerStream::AUDIO>::NeedsBitstreamConversion(
 }
 
 // static
-void DecoderStreamTraits<DemuxerStream::AUDIO>::ReportStatistics(
-    const StatisticsCB& statistics_cb,
-    int bytes_decoded) {
-  PipelineStatistics statistics;
-  statistics.audio_bytes_decoded = bytes_decoded;
-  statistics_cb.Run(statistics);
-}
-
-// static
 scoped_refptr<DecoderStreamTraits<DemuxerStream::AUDIO>::OutputType>
     DecoderStreamTraits<DemuxerStream::AUDIO>::CreateEOSOutput() {
   return OutputType::CreateEOSBuffer();
@@ -46,6 +37,14 @@ DecoderStreamTraits<DemuxerStream::AUDIO>::DecoderStreamTraits(
     const scoped_refptr<MediaLog>& media_log)
     : media_log_(media_log) {}
 
+void DecoderStreamTraits<DemuxerStream::AUDIO>::ReportStatistics(
+    const StatisticsCB& statistics_cb,
+    int bytes_decoded) {
+  PipelineStatistics statistics;
+  statistics.audio_bytes_decoded = bytes_decoded;
+  statistics_cb.Run(statistics);
+}
+
 void DecoderStreamTraits<DemuxerStream::AUDIO>::InitializeDecoder(
     DecoderType* decoder,
     DemuxerStream* stream,
@@ -90,20 +89,26 @@ bool DecoderStreamTraits<DemuxerStream::VIDEO>::NeedsBitstreamConversion(
 }
 
 // static
+scoped_refptr<DecoderStreamTraits<DemuxerStream::VIDEO>::OutputType>
+DecoderStreamTraits<DemuxerStream::VIDEO>::CreateEOSOutput() {
+  return OutputType::CreateEOSFrame();
+}
+
+DecoderStreamTraits<DemuxerStream::VIDEO>::DecoderStreamTraits(
+    const scoped_refptr<MediaLog>& media_log)
+    // Randomly selected number of samples to keep.
+    : keyframe_distance_average_(16) {}
+
 void DecoderStreamTraits<DemuxerStream::VIDEO>::ReportStatistics(
     const StatisticsCB& statistics_cb,
     int bytes_decoded) {
   PipelineStatistics statistics;
   statistics.video_bytes_decoded = bytes_decoded;
+  statistics.video_keyframe_distance_average_ms =
+      keyframe_distance_average_.Average().InMilliseconds();
   statistics_cb.Run(statistics);
 }
 
-// static
-scoped_refptr<DecoderStreamTraits<DemuxerStream::VIDEO>::OutputType>
-    DecoderStreamTraits<DemuxerStream::VIDEO>::CreateEOSOutput() {
-  return OutputType::CreateEOSFrame();
-}
-
 void DecoderStreamTraits<DemuxerStream::VIDEO>::InitializeDecoder(
     DecoderType* decoder,
     DemuxerStream* stream,
@@ -141,10 +146,11 @@ void DecoderStreamTraits<DemuxerStream::VIDEO>::OnDecode(
     return;
   }
 
-  UMA_HISTOGRAM_MEDIUM_TIMES(
-      "Media.Video.KeyFrameDistance",
-      current_frame_timestamp - last_keyframe_timestamp_);
+  base::TimeDelta frame_distance =
+      current_frame_timestamp - last_keyframe_timestamp_;
+  UMA_HISTOGRAM_MEDIUM_TIMES("Media.Video.KeyFrameDistance", frame_distance);
   last_keyframe_timestamp_ = current_frame_timestamp;
+  keyframe_distance_average_.AddSample(frame_distance);
 }
 
 }  // namespace media