Log codec IDs for MediaSource content.

media/filters/ffmpeg_audio_decoder.cc

 // Copyright (c) 2012 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/filters/ffmpeg_audio_decoder.h"
 
 #include "base/callback_helpers.h"
 #include "base/single_thread_task_runner.h"
 #include "media/base/audio_buffer.h"
 #include "media/base/audio_bus.h"
@@ skipping 108 matching lines @@
   // Now create an AVBufferRef for the data just allocated. It will own the
   // reference to the AudioBuffer object.
   void* opaque = NULL;
   buffer.swap(reinterpret_cast<AudioBuffer**>(&opaque));
   frame->buf[0] = av_buffer_create(
       frame->data[0], buffer_size_in_bytes, ReleaseAudioBufferImpl, opaque, 0);
   return 0;
 }
 
 FFmpegAudioDecoder::FFmpegAudioDecoder(
-    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner)
-    : task_runner_(task_runner), state_(kUninitialized), av_sample_format_(0) {
+    const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+    const LogCB& log_cb)
+    : task_runner_(task_runner),
+      state_(kUninitialized),
+      av_sample_format_(0),
+      log_cb_(log_cb) {
 }
 
 FFmpegAudioDecoder::~FFmpegAudioDecoder() {
   DCHECK_EQ(state_, kUninitialized);
   DCHECK(!codec_context_);
   DCHECK(!av_frame_);
 }
 
 void FFmpegAudioDecoder::Initialize(const AudioDecoderConfig& config,
                                     const PipelineStatusCB& status_cb) {
@@ skipping 203 matching lines @@
           channels != ChannelLayoutToChannelCount(config_.channel_layout()) ||
           av_frame_->format != av_sample_format_) {
         DLOG(ERROR) << "Unsupported midstream configuration change!"
                     << " Sample Rate: " << av_frame_->sample_rate << " vs "
                     << config_.samples_per_second()
                     << ", Channels: " << channels << " vs "
                     << ChannelLayoutToChannelCount(config_.channel_layout())
                     << ", Sample Format: " << av_frame_->format << " vs "
                     << av_sample_format_;
 
+        if ((config_.codec() == kCodecAAC) &&
+            av_frame_->sample_rate == 2 * config_.samples_per_second()) {

[scherkus (not reviewing), 2014/05/08 00:26:14]

nit: it's funny you put the ()'s around the simple comparison to kCodecAAC but
not the 2 * config_.samples_per_second() bit :)

[acolwell GONE FROM CHROMIUM, 2014/05/08 00:57:01]

Yeah. Not sure why I did that. () removed.

+          MEDIA_LOG(log_cb_) << "Implicit HE-AAC signalling is being used."

[scherkus (not reviewing), 2014/05/07 20:25:53]

should this be moved closer to MSE code instead of being inside of the decoder?

[acolwell GONE FROM CHROMIUM, 2014/05/07 20:47:45]

We can't. Implict signalling of HE-AAC can only be detected by decoding the
packet. All the info in the header looks like AAC-LC. The only way to tell that
it is HE-AAC is to decode the AAC-LC data and notice that some HE-AAC follows
it. This is a backwards compatibility "feature". 

The REAL fix here is to defer audio device initialization until after the first
frame is decoded, but that is a non-trivial change. This is a stopgap measure to
help people understand what to do until we actually make the hard change.

+                             << " Please use mp4a.40.5 instead of mp4a.40.2 in"
+                             << " the mimetype.";
+        }
         // This is an unrecoverable error, so bail out.
         queued_audio_.clear();
         av_frame_unref(av_frame_.get());
         return false;
       }
 
       // Get the AudioBuffer that the data was decoded into. Adjust the number
       // of frames, in case fewer than requested were actually decoded.
       output = reinterpret_cast<AudioBuffer*>(
           av_buffer_get_opaque(av_frame_->buf[0]));
@@ skipping 80 matching lines @@
 
   ResetTimestampState();
   return true;
 }
 
 void FFmpegAudioDecoder::ResetTimestampState() {
   discard_helper_->Reset(config_.codec_delay());
 }
 
 }  // namespace media