[Media] Disable background video optimization for streaming videos

media/blink/webmediaplayer_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/blink/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 #include <string>
@@ skipping 1318 matching lines @@
   opaque_ = opaque;
   // Modify content opaqueness of cc::Layer directly so that
   // SetContentsOpaqueIsFixed is ignored.
   if (video_weblayer_)
     video_weblayer_->layer()->SetContentsOpaque(opaque_);
 }
 
 void WebMediaPlayerImpl::OnHidden() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
-  if (IsBackgroundVideoTrackOptimizationEnabled())
+  if (!IsStreaming() && IsBackgroundVideoTrackOptimizationEnabled())
     selectedVideoTrackChanged(nullptr);
 
   if (watch_time_reporter_)
     watch_time_reporter_->OnHidden();
 
   UpdatePlayState();
 
   // Schedule suspended playing media to be paused if the user doesn't come back
   // to it within some timeout period to avoid any autoplay surprises.
   ScheduleIdlePauseTimer();
 }
 
 void WebMediaPlayerImpl::OnShown() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
   if (watch_time_reporter_)
     watch_time_reporter_->OnShown();
 
-  if (IsBackgroundVideoTrackOptimizationEnabled() &&
+  if (!IsStreaming() && IsBackgroundVideoTrackOptimizationEnabled() &&
       client_->hasSelectedVideoTrack()) {
     WebMediaPlayer::TrackId trackId = client_->getSelectedVideoTrackId();
     selectedVideoTrackChanged(&trackId);
   }
 
   must_suspend_ = false;
   background_pause_timer_.Stop();
 
   UpdatePlayState();
 }
@@ skipping 273 matching lines @@
 
     chunk_demuxer_ = new ChunkDemuxer(
         BIND_TO_RENDER_LOOP(&WebMediaPlayerImpl::OnDemuxerOpened),
         encrypted_media_init_data_cb, media_log_);
     demuxer_.reset(chunk_demuxer_);
   }
 
   // TODO(sandersd): FileSystem objects may also be non-static, but due to our
   // caching layer such situations are broken already. http://crbug.com/593159
   bool is_static = !chunk_demuxer_;
-  bool is_streaming = data_source_ && data_source_->IsStreaming();
+  bool is_streaming = IsStreaming();
   UMA_HISTOGRAM_BOOLEAN("Media.IsStreaming", is_streaming);
 
   // ... and we're ready to go!
   // TODO(sandersd): On Android, defer Start() if the tab is not visible.
   seeking_ = true;
   pipeline_controller_.Start(demuxer_.get(), this, is_streaming, is_static);
 }
 
 void WebMediaPlayerImpl::SetNetworkState(WebMediaPlayer::NetworkState state) {
   DVLOG(1) << __func__ << "(" << state << ")";
@@ skipping 68 matching lines @@
 }
 
 void WebMediaPlayerImpl::UpdatePlayState() {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
 #if defined(OS_ANDROID)  // WMPI_CAST
   bool is_remote = isRemote();
   bool is_streaming = false;
 #else
   bool is_remote = false;
-  bool is_streaming = data_source_ && data_source_->IsStreaming();
+  bool is_streaming = IsStreaming();
 #endif
 
   bool is_suspended = pipeline_controller_.IsSuspended();
   bool is_backgrounded = IsBackgroundedSuspendEnabled() && IsHidden();
   PlayState state = UpdatePlayState_ComputePlayState(
       is_remote, is_streaming, is_suspended, is_backgrounded);
   SetDelegateState(state.delegate_state);
   SetMemoryReportingState(state.is_memory_reporting_enabled);
   SetSuspendState(state.is_suspended || pending_suspend_resume_cycle_);
 }
@@ skipping 272 matching lines @@
   else
     watch_time_reporter_->OnShown();
 }
 
 bool WebMediaPlayerImpl::IsHidden() const {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
   return delegate_ && delegate_->IsHidden();
 }
 
+bool WebMediaPlayerImpl::IsStreaming() const {
+  return !std::isfinite(duration()) ||

[sandersd (OOO until July 31), 2017/01/06 21:20:28]

FYI: I was just looking through this code, and everything else is using
video_stream->liveness(). This is the bit that enables low-delay decoding, so
it's worth verifying that the computation is the same.

[whywhat, 2017/01/06 22:19:57]

Hm, liveness seems to depend on the stream parser:
- ffmpeg checks for duration to be infinite:
https://cs.chromium.org/chromium/src/media/formats/webm/webm_stream_parser.cc...
- chunk (webm stream?) checks for negative duration:
https://cs.chromium.org/chromium/src/media/formats/webm/webm_stream_parser.cc...

I'm happy to use that but need to find a way to propagate it from demuxer stream
to WMPI

+         (data_source_ && data_source_->IsStreaming());
+}
+
 bool WebMediaPlayerImpl::DoesOverlaySupportMetadata() const {
   return pipeline_metadata_.video_rotation == VIDEO_ROTATION_0;
 }
 
 void WebMediaPlayerImpl::ActivateViewportIntersectionMonitoring(bool activate) {
   DCHECK(main_task_runner_->BelongsToCurrentThread());
 
   client_->activateViewportIntersectionMonitoring(activate);
 }
 
 }  // namespace media