Render inband text tracks in the media pipeline

media/base/pipeline.cc

Index: media/base/pipeline.cc
diff --git a/media/base/pipeline.cc b/media/base/pipeline.cc
index 9790c61cb5ca792c12d44a3f7b1b45392892565d..c171e405bf10d4e9c0cfaa246a59b6e2c5073ebf 100644
--- a/media/base/pipeline.cc
+++ b/media/base/pipeline.cc
@@ -21,6 +21,8 @@
 #include "media/base/clock.h"
 #include "media/base/filter_collection.h"
 #include "media/base/media_log.h"
+#include "media/base/text_decoder.h"
+#include "media/base/text_renderer.h"
 #include "media/base/video_decoder.h"
 #include "media/base/video_decoder_config.h"
 #include "media/base/video_renderer.h"
@@ -44,9 +46,11 @@ Pipeline::Pipeline(const scoped_refptr<base::MessageLoopProxy>& message_loop,
       status_(PIPELINE_OK),
       has_audio_(false),
       has_video_(false),
+      has_text_(false),
       state_(kCreated),
       audio_ended_(false),
       video_ended_(false),
+      text_ended_(false),
       audio_disabled_(false),
       demuxer_(NULL),
       creation_time_(default_tick_clock_.NowTicks()) {
@@ -114,6 +118,11 @@ bool Pipeline::HasVideo() const {
   return has_video_;
 }
 
+bool Pipeline::HasText() const {
+  base::AutoLock auto_lock(lock_);
+  return has_text_;
+}
+
 float Pipeline::GetPlaybackRate() const {
   base::AutoLock auto_lock(lock_);
   return playback_rate_;
@@ -232,6 +241,7 @@ const char* Pipeline::GetStateString(State state) {
     RETURN_STRING(kInitDemuxer);
     RETURN_STRING(kInitAudioRenderer);
     RETURN_STRING(kInitVideoRenderer);
+    RETURN_STRING(kInitTextRenderer);
     RETURN_STRING(kInitPrerolling);
     RETURN_STRING(kSeeking);
     RETURN_STRING(kStarting);
@@ -261,14 +271,23 @@ Pipeline::State Pipeline::GetNextState() const {
         return kInitAudioRenderer;
       if (demuxer_->GetStream(DemuxerStream::VIDEO))
         return kInitVideoRenderer;
+      if (demuxer_->GetStream(DemuxerStream::TEXT))
+        return kInitTextRenderer;
       return kInitPrerolling;
 
     case kInitAudioRenderer:
       if (demuxer_->GetStream(DemuxerStream::VIDEO))
         return kInitVideoRenderer;
+      if (demuxer_->GetStream(DemuxerStream::TEXT))
+        return kInitTextRenderer;
       return kInitPrerolling;
 
     case kInitVideoRenderer:
+      if (demuxer_->GetStream(DemuxerStream::TEXT))
+        return kInitTextRenderer;
+      return kInitPrerolling;
+
+    case kInitTextRenderer:
       return kInitPrerolling;
 
     case kInitPrerolling:
@@ -435,6 +454,9 @@ void Pipeline::StateTransitionTask(PipelineStatus status) {
     case kInitVideoRenderer:
       return InitializeVideoRenderer(done_cb);
 
+    case kInitTextRenderer:
+      return InitializeTextRenderer(done_cb);
+
     case kInitPrerolling:
       filter_collection_.reset();
       {
@@ -449,6 +471,7 @@ void Pipeline::StateTransitionTask(PipelineStatus status) {
         // track.
         has_audio_ = audio_renderer_ != NULL && !audio_disabled_;
         has_video_ = video_renderer_ != NULL;
+        has_text_ = text_renderer_ != NULL;
       }
       if (!audio_renderer_ && !video_renderer_) {
         done_cb.Run(PIPELINE_ERROR_COULD_NOT_RENDER);
@@ -537,6 +560,10 @@ void Pipeline::DoSeek(
     bound_fns.Push(base::Bind(
         &VideoRenderer::Pause, base::Unretained(video_renderer_.get())));
   }
+  if (text_renderer_) {
+    bound_fns.Push(base::Bind(
+        &TextRenderer::Pause, base::Unretained(text_renderer_.get())));
+  }
 
   // Flush.
   if (audio_renderer_) {
@@ -586,6 +613,11 @@ void Pipeline::DoPlay(const PipelineStatusCB& done_cb) {
         &VideoRenderer::Play, base::Unretained(video_renderer_.get())));
   }
 
+  if (text_renderer_) {
+    bound_fns.Push(base::Bind(
+        &TextRenderer::Play, base::Unretained(text_renderer_.get())));
+  }
+
   pending_callbacks_ = SerialRunner::Run(bound_fns, done_cb);
 }
 
@@ -609,6 +641,11 @@ void Pipeline::DoStop(const PipelineStatusCB& done_cb) {
         &VideoRenderer::Stop, base::Unretained(video_renderer_.get())));
   }
 
+  if (text_renderer_) {
+    bound_fns.Push(base::Bind(
+        &TextRenderer::Stop, base::Unretained(text_renderer_.get())));
+  }
+
   pending_callbacks_ = SerialRunner::Run(bound_fns, done_cb);
 }
 
@@ -625,6 +662,7 @@ void Pipeline::OnStopCompleted(PipelineStatus status) {
   filter_collection_.reset();
   audio_renderer_.reset();
   video_renderer_.reset();
+  text_renderer_.reset();
   demuxer_ = NULL;
 
   // If we stop during initialization/seeking we want to run |seek_cb_|
@@ -685,6 +723,13 @@ void Pipeline::OnVideoRendererEnded() {
   media_log_->AddEvent(media_log_->CreateEvent(MediaLogEvent::VIDEO_ENDED));
 }
 
+void Pipeline::OnTextRendererEnded() {
+  // Force post to process ended messages after current execution frame.
+  message_loop_->PostTask(FROM_HERE, base::Bind(
+      &Pipeline::DoTextRendererEnded, base::Unretained(this)));
+  media_log_->AddEvent(media_log_->CreateEvent(MediaLogEvent::TEXT_ENDED));
+}
+
 // Called from any thread.
 void Pipeline::OnUpdateStatistics(const PipelineStatistics& stats) {
   base::AutoLock auto_lock(lock_);
@@ -802,6 +847,7 @@ void Pipeline::SeekTask(TimeDelta time, const PipelineStatusCB& seek_cb) {
   seek_cb_ = seek_cb;
   audio_ended_ = false;
   video_ended_ = false;
+  text_ended_ = false;
 
   // Kick off seeking!
   {
@@ -845,6 +891,18 @@ void Pipeline::DoVideoRendererEnded() {
   RunEndedCallbackIfNeeded();
 }
 
+void Pipeline::DoTextRendererEnded() {
+  DCHECK(message_loop_->BelongsToCurrentThread());
+
+  if (state_ != kStarted)
+    return;
+
+  DCHECK(!text_ended_);
+  text_ended_ = true;
+
+  RunEndedCallbackIfNeeded();
+}
+
 void Pipeline::RunEndedCallbackIfNeeded() {
   DCHECK(message_loop_->BelongsToCurrentThread());
 
@@ -854,6 +912,9 @@ void Pipeline::RunEndedCallbackIfNeeded() {
   if (video_renderer_ && !video_ended_)
     return;
 
+  if (text_renderer_ && !text_ended_)
+    return;
+
   {
     base::AutoLock auto_lock(lock_);
     clock_->EndOfStream();
@@ -925,6 +986,16 @@ void Pipeline::InitializeVideoRenderer(const PipelineStatusCB& done_cb) {
       base::Bind(&Pipeline::GetMediaDuration, base::Unretained(this)));
 }
 
+void Pipeline::InitializeTextRenderer(const PipelineStatusCB& done_cb) {
+  DCHECK(message_loop_->BelongsToCurrentThread());
+
+  text_renderer_ = filter_collection_->GetTextRenderer();
+  text_renderer_->Initialize(
+      demuxer_,
+      done_cb,
+      base::Bind(&Pipeline::OnTextRendererEnded, base::Unretained(this)));
+}
+
 void Pipeline::OnAudioUnderflow() {
   if (!message_loop_->BelongsToCurrentThread()) {
     message_loop_->PostTask(FROM_HERE, base::Bind(