Interpolate media time for mojo rendering pipeline.

media/mojo/services/mojo_renderer_service.cc

 // Copyright 2014 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/mojo/services/mojo_renderer_service.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "media/base/audio_renderer_sink.h"
@@ skipping 11 matching lines @@
 
 MojoRendererService::MojoRendererService(
     base::WeakPtr<MojoCdmServiceContext> mojo_cdm_service_context,
     scoped_refptr<AudioRendererSink> audio_sink,
     std::unique_ptr<VideoRendererSink> video_sink,
     std::unique_ptr<media::Renderer> renderer,
     mojo::InterfaceRequest<mojom::Renderer> request)
     : binding_(this, std::move(request)),
       mojo_cdm_service_context_(mojo_cdm_service_context),
       state_(STATE_UNINITIALIZED),
+      playback_rate_(0),
       audio_sink_(std::move(audio_sink)),
       video_sink_(std::move(video_sink)),
       renderer_(std::move(renderer)),
       weak_factory_(this) {
   DVLOG(1) << __FUNCTION__;
   DCHECK(renderer_);
 
   weak_this_ = weak_factory_.GetWeakPtr();
 }
 
@@ skipping 38 matching lines @@
 
 void MojoRendererService::StartPlayingFrom(base::TimeDelta time_delta) {
   DVLOG(2) << __FUNCTION__ << ": " << time_delta;
   renderer_->StartPlayingFrom(time_delta);
   SchedulePeriodicMediaTimeUpdates();
 }
 
 void MojoRendererService::SetPlaybackRate(double playback_rate) {
   DVLOG(2) << __FUNCTION__ << ": " << playback_rate;
   DCHECK(state_ == STATE_PLAYING || state_ == STATE_ERROR);
+  playback_rate_ = playback_rate;
   renderer_->SetPlaybackRate(playback_rate);
 }
 
 void MojoRendererService::SetVolume(float volume) {
   renderer_->SetVolume(volume);
 }
 
 void MojoRendererService::SetCdm(int32_t cdm_id,
                                  const SetCdmCallback& callback) {
   if (!mojo_cdm_service_context_) {
@@ skipping 81 matching lines @@
     state_ = STATE_ERROR;
     callback.Run(false);
     return;
   }
 
   state_ = STATE_PLAYING;
   callback.Run(true);
 }
 
 void MojoRendererService::UpdateMediaTime(bool force) {
-  base::TimeDelta media_time = renderer_->GetMediaTime();
+  const base::TimeDelta media_time = renderer_->GetMediaTime();
   if (!force && media_time == last_media_time_)
     return;
 
-  client_->OnTimeUpdate(media_time, media_time);
+  base::TimeDelta max_time = media_time;
+  // Allow some slop to account for delays in scheduling time update tasks.
+  if (time_update_timer_.IsRunning() && (playback_rate_ > 0))
+    max_time += base::TimeDelta::FromMilliseconds(2 * kTimeUpdateIntervalMs);
+
+  client_->OnTimeUpdate(media_time, max_time, base::TimeTicks::Now());
   last_media_time_ = media_time;
 }
 
 void MojoRendererService::CancelPeriodicMediaTimeUpdates() {
   DVLOG(2) << __FUNCTION__;
+
+  time_update_timer_.Stop();
   UpdateMediaTime(false);
-  time_update_timer_.Stop();
 }
 
 void MojoRendererService::SchedulePeriodicMediaTimeUpdates() {
   DVLOG(2) << __FUNCTION__;
+
   UpdateMediaTime(true);
   time_update_timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromMilliseconds(kTimeUpdateIntervalMs),
+      FROM_HERE, base::TimeDelta::FromMilliseconds(kTimeUpdateIntervalMs),
       base::Bind(&MojoRendererService::UpdateMediaTime, weak_this_, false));
 }
 
 void MojoRendererService::OnFlushCompleted(const FlushCallback& callback) {
   DVLOG(1) << __FUNCTION__;
   DCHECK_EQ(state_, STATE_FLUSHING);
   state_ = STATE_PLAYING;
   callback.Run();
 }
 
 void MojoRendererService::OnCdmAttached(
     scoped_refptr<MediaKeys> cdm,
     const base::Callback<void(bool)>& callback,
     bool success) {
   DVLOG(1) << __FUNCTION__ << "(" << success << ")";
 
   if (success)
     cdm_ = cdm;
 
   callback.Run(success);
 }
 
 }  // namespace media