Use a shared thread for media operations.

This reduces the number of threads created per media element by one.

BUG=61293
R=acolwell@chromium.org, jamesr@chromium.org, jochen@chromium.org

Review URL: https://codereview.chromium.org/15005005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@199531 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 29 insertions, 22 deletions

diff --git a/webkit/media/webmediaplayer_impl.cc b/webkit/media/webmediaplayer_impl.cc
index 41fd0b3..43880cb 100644
--- a/webkit/media/webmediaplayer_impl.cc
+++ b/webkit/media/webmediaplayer_impl.cc
@@ -128,7 +128,7 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
       network_state_(WebMediaPlayer::NetworkStateEmpty),
       ready_state_(WebMediaPlayer::ReadyStateHaveNothing),
       main_loop_(base::MessageLoopProxy::current()),
-      media_thread_("MediaPipeline"),
+      media_loop_(params.message_loop_proxy()),
       paused_(true),
       seeking_(false),
       playback_rate_(0.0f),
@@ -150,9 +150,7 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
   media_log_->AddEvent(
       media_log_->CreateEvent(media::MediaLogEvent::WEBMEDIAPLAYER_CREATED));
 
-  CHECK(media_thread_.Start());
-  pipeline_.reset(new media::Pipeline(
-      media_thread_.message_loop_proxy(), media_log_));
+  pipeline_.reset(new media::Pipeline(media_loop_, media_log_));
 
   // Let V8 know we started new thread if we did not do it yet.
   // Made separate task to avoid deletion of player currently being created.
@@ -181,7 +179,7 @@ WebMediaPlayerImpl::WebMediaPlayerImpl(
   // Use the null sink if no sink was provided.
   audio_source_provider_ = new WebAudioSourceProviderImpl(
       params.audio_renderer_sink() ? params.audio_renderer_sink() :
-      new media::NullAudioSink(media_thread_.message_loop_proxy()));
+      new media::NullAudioSink(media_loop_));
 }
 
 WebMediaPlayerImpl::~WebMediaPlayerImpl() {
@@ -1072,7 +1070,7 @@ void WebMediaPlayerImpl::StartPipeline(WebKit::WebMediaSource* media_source) {
     DCHECK(data_source_);
 
     demuxer_.reset(new media::FFmpegDemuxer(
-        media_thread_.message_loop_proxy(), data_source_.get(),
+        media_loop_, data_source_.get(),
         BIND_TO_RENDER_LOOP_2(&WebMediaPlayerImpl::OnNeedKey, "", "")));
   } else {
     DCHECK(!chunk_demuxer_);
@@ -1104,15 +1102,13 @@ void WebMediaPlayerImpl::StartPipeline(WebKit::WebMediaSource* media_source) {
 
   // Create our audio decoders and renderer.
   ScopedVector<media::AudioDecoder> audio_decoders;
-  audio_decoders.push_back(new media::FFmpegAudioDecoder(
-      media_thread_.message_loop_proxy()));
+  audio_decoders.push_back(new media::FFmpegAudioDecoder(media_loop_));
   if (cmd_line->HasSwitch(switches::kEnableOpusPlayback)) {
-    audio_decoders.push_back(new media::OpusAudioDecoder(
-        media_thread_.message_loop_proxy()));
+    audio_decoders.push_back(new media::OpusAudioDecoder(media_loop_));
   }
 
   scoped_ptr<media::AudioRenderer> audio_renderer(
-      new media::AudioRendererImpl(media_thread_.message_loop_proxy(),
+      new media::AudioRendererImpl(media_loop_,
                                    audio_source_provider_,
                                    audio_decoders.Pass(),
                                    set_decryptor_ready_cb));
@@ -1123,7 +1119,7 @@ void WebMediaPlayerImpl::StartPipeline(WebKit::WebMediaSource* media_source) {
 
   if (gpu_factories_) {
     video_decoders.push_back(new media::GpuVideoDecoder(
-        media_thread_.message_loop_proxy(), gpu_factories_));
+        media_loop_, gpu_factories_));
   }
 
   // TODO(phajdan.jr): Remove ifdefs when libvpx with vp9 support is released
@@ -1131,17 +1127,15 @@ void WebMediaPlayerImpl::StartPipeline(WebKit::WebMediaSource* media_source) {
 #if !defined(MEDIA_DISABLE_LIBVPX)
   if (cmd_line->HasSwitch(switches::kEnableVp9Playback) ||
       cmd_line->HasSwitch(switches::kEnableVp8AlphaPlayback)) {
-    video_decoders.push_back(new media::VpxVideoDecoder(
-        media_thread_.message_loop_proxy()));
+    video_decoders.push_back(new media::VpxVideoDecoder(media_loop_));
   }
 #endif  // !defined(MEDIA_DISABLE_LIBVPX)
 
-  video_decoders.push_back(new media::FFmpegVideoDecoder(
-      media_thread_.message_loop_proxy()));
+  video_decoders.push_back(new media::FFmpegVideoDecoder(media_loop_));
 
   scoped_ptr<media::VideoRenderer> video_renderer(
       new media::VideoRendererBase(
-          media_thread_.message_loop_proxy(),
+          media_loop_,
           video_decoders.Pass(),
           set_decryptor_ready_cb,
           base::Bind(&WebMediaPlayerImpl::FrameReady, base::Unretained(this)),
@@ -1211,8 +1205,6 @@ void WebMediaPlayerImpl::Destroy() {
     incremented_externally_allocated_memory_ = false;
   }
 
-  media_thread_.Stop();
-
   // Release any final references now that everything has stopped.
   pipeline_.reset();
   demuxer_.reset();
diff --git a/webkit/media/webmediaplayer_impl.h b/webkit/media/webmediaplayer_impl.h
index 3772a8b..16944ae 100644
--- a/webkit/media/webmediaplayer_impl.h
+++ b/webkit/media/webmediaplayer_impl.h
@@ -280,7 +280,7 @@ class WebMediaPlayerImpl
   const scoped_refptr<base::MessageLoopProxy> main_loop_;
 
   scoped_ptr<media::Pipeline> pipeline_;
-  base::Thread media_thread_;
+  scoped_refptr<base::MessageLoopProxy> media_loop_;
 
   // The currently selected key system. Empty string means that no key system
   // has been selected.
diff --git a/webkit/media/webmediaplayer_params.cc b/webkit/media/webmediaplayer_params.cc
index 6f013b6..4c0f74e 100644
--- a/webkit/media/webmediaplayer_params.cc
+++ b/webkit/media/webmediaplayer_params.cc
@@ -4,18 +4,22 @@
 
 #include "webkit/media/webmediaplayer_params.h"
 
+#include "base/message_loop_proxy.h"
 #include "media/base/audio_renderer_sink.h"
 #include "media/base/media_log.h"
 
 namespace webkit_media {
 
 WebMediaPlayerParams::WebMediaPlayerParams(
+    const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy,
     const scoped_refptr<media::AudioRendererSink>& audio_renderer_sink,
     const scoped_refptr<media::GpuVideoDecoder::Factories>& gpu_factories,
     const scoped_refptr<media::MediaLog>& media_log)
-    : audio_renderer_sink_(audio_renderer_sink),
+    : message_loop_proxy_(message_loop_proxy),
+      audio_renderer_sink_(audio_renderer_sink),
       gpu_factories_(gpu_factories),
       media_log_(media_log) {
+  DCHECK(message_loop_proxy);
   DCHECK(media_log_);
 }
 
diff --git a/webkit/media/webmediaplayer_params.h b/webkit/media/webmediaplayer_params.h
index 5fb2de9..d9a2244 100644
--- a/webkit/media/webmediaplayer_params.h
+++ b/webkit/media/webmediaplayer_params.h
@@ -8,6 +8,10 @@
 #include "base/memory/ref_counted.h"
 #include "media/filters/gpu_video_decoder.h"
 
+namespace base {
+class MessageLoopProxy;
+}
+
 namespace media {
 class AudioRendererSink;
 class MediaLog;
@@ -19,13 +23,19 @@ namespace webkit_media {
 // to plumb arguments through various abstraction layers.
 class WebMediaPlayerParams {
  public:
-  // |media_log| is the only required parameter; all others may be null.
+  // |message_loop_proxy| and |media_log| are the only required parameters;
+  // all others may be null.
   WebMediaPlayerParams(
+      const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy,
       const scoped_refptr<media::AudioRendererSink>& audio_renderer_sink,
       const scoped_refptr<media::GpuVideoDecoder::Factories>& gpu_factories,
       const scoped_refptr<media::MediaLog>& media_log);
   ~WebMediaPlayerParams();
 
+  const scoped_refptr<base::MessageLoopProxy>& message_loop_proxy() const {
+    return message_loop_proxy_;
+  }
+
   const scoped_refptr<media::AudioRendererSink>& audio_renderer_sink() const {
     return audio_renderer_sink_;
   }
@@ -40,6 +50,7 @@ class WebMediaPlayerParams {
   }
 
  private:
+  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
   scoped_refptr<media::AudioRendererSink> audio_renderer_sink_;
   scoped_refptr<media::GpuVideoDecoder::Factories> gpu_factories_;
   scoped_refptr<media::MediaLog> media_log_;