Add callback in VideoDecoder and AudioDecoder to return decoded frames.

media/filters/ffmpeg_audio_decoder.cc

Index: media/filters/ffmpeg_audio_decoder.cc
diff --git a/media/filters/ffmpeg_audio_decoder.cc b/media/filters/ffmpeg_audio_decoder.cc
index 00832a05abf048953b45fce0b040667b3ded9679..30673a7b0c1da213770ab76c0a62358db02dc49b 100644
--- a/media/filters/ffmpeg_audio_decoder.cc
+++ b/media/filters/ffmpeg_audio_decoder.cc
@@ -141,7 +141,8 @@ FFmpegAudioDecoder::~FFmpegAudioDecoder() {
 }
 
 void FFmpegAudioDecoder::Initialize(const AudioDecoderConfig& config,
-                                    const PipelineStatusCB& status_cb) {
+                                    const PipelineStatusCB& status_cb,
+                                    const OutputCB& output_cb) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(!config.is_encrypted());
 
@@ -156,6 +157,7 @@ void FFmpegAudioDecoder::Initialize(const AudioDecoderConfig& config,
   }
 
   // Success!
+  output_cb_ = BindToCurrentLoop(output_cb);
   state_ = kNormal;
   initialize_cb.Run(PIPELINE_OK);
 }
@@ -168,33 +170,24 @@ void FFmpegAudioDecoder::Decode(const scoped_refptr<DecoderBuffer>& buffer,
   DecodeCB decode_cb_bound = BindToCurrentLoop(decode_cb);
 
   if (state_ == kError) {
-    decode_cb_bound.Run(kDecodeError, NULL);
+    decode_cb_bound.Run(kDecodeError);
     return;
   }
 
-  // Return empty frames if decoding has finished.
+  // Do nothing if decoding has finished.
   if (state_ == kDecodeFinished) {
-    decode_cb_bound.Run(kOk, AudioBuffer::CreateEOSBuffer());
+    decode_cb_bound.Run(kOk);
     return;
   }
 
   if (!buffer) {

[xhwang, 2014/06/05 21:53:50]

hmm, should this ever happen?

[Sergey Ulanov, 2014/06/06 22:49:40]

Done.

-    decode_cb_bound.Run(kAborted, NULL);
+    decode_cb_bound.Run(kAborted);
     return;
   }
 
   DecodeBuffer(buffer, decode_cb_bound);
 }
 
-scoped_refptr<AudioBuffer> FFmpegAudioDecoder::GetDecodeOutput() {
-  DCHECK(task_runner_->BelongsToCurrentThread());
-  if (queued_audio_.empty())
-    return NULL;
-  scoped_refptr<AudioBuffer> out = queued_audio_.front();
-  queued_audio_.pop_front();
-  return out;
-}
-
 void FFmpegAudioDecoder::Reset(const base::Closure& closure) {
   DCHECK(task_runner_->BelongsToCurrentThread());
 
@@ -257,7 +250,7 @@ void FFmpegAudioDecoder::DecodeBuffer(
   // occurs with some damaged files.
   if (!buffer->end_of_stream() && buffer->timestamp() == kNoTimestamp()) {
     DVLOG(1) << "Received a buffer without timestamps!";
-    decode_cb.Run(kDecodeError, NULL);
+    decode_cb.Run(kDecodeError);
     return;
   }
 
@@ -278,30 +271,20 @@ void FFmpegAudioDecoder::DecodeBuffer(
 
   if (!FFmpegDecode(buffer)) {
     state_ = kError;
-    decode_cb.Run(kDecodeError, NULL);
+    decode_cb.Run(kDecodeError);
     return;
   }
 
-  if (queued_audio_.empty()) {
-    if (state_ == kFlushCodec) {
-      DCHECK(buffer->end_of_stream());
-      state_ = kDecodeFinished;
-      decode_cb.Run(kOk, AudioBuffer::CreateEOSBuffer());
-      return;
-    }
-
-    decode_cb.Run(kNotEnoughData, NULL);
-    return;
+  if (state_ == kFlushCodec) {
+    state_ = kDecodeFinished;
+    output_cb_.Run(AudioBuffer::CreateEOSBuffer());

[xhwang, 2014/06/05 21:53:50]

should we keep calling FFmpegDecode(EOS) until the codec is completely flushed?

[Sergey Ulanov, 2014/06/06 22:49:40]

There is a loop in FFmpegDecode() which should flush all data.

   }
 
-  decode_cb.Run(kOk, queued_audio_.front());
-  queued_audio_.pop_front();
+  decode_cb.Run(kOk);
 }
 
 bool FFmpegAudioDecoder::FFmpegDecode(
     const scoped_refptr<DecoderBuffer>& buffer) {
-  DCHECK(queued_audio_.empty());
-
   AVPacket packet;
   av_init_packet(&packet);
   if (buffer->end_of_stream()) {
@@ -362,7 +345,6 @@ bool FFmpegAudioDecoder::FFmpegDecode(
                              << " the mimetype.";
         }
         // This is an unrecoverable error, so bail out.
-        queued_audio_.clear();
         av_frame_unref(av_frame_.get());
         return false;
       }
@@ -386,9 +368,9 @@ bool FFmpegAudioDecoder::FFmpegDecode(
     const int decoded_frames = frame_decoded ? output->frame_count() : 0;
     if (IsEndOfStream(result, decoded_frames, buffer)) {
       DCHECK_EQ(packet.size, 0);
-      queued_audio_.push_back(AudioBuffer::CreateEOSBuffer());
+      output_cb_.Run(AudioBuffer::CreateEOSBuffer());
     } else if (discard_helper_->ProcessBuffers(buffer, output)) {
-      queued_audio_.push_back(output);
+      output_cb_.Run(output);
     }
   } while (packet.size > 0);