Re-add AC3/EAC3 audio demuxing support

media/ffmpeg/ffmpeg_common.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/ffmpeg/ffmpeg_common.h"
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 47 matching lines @@
 int64 ConvertToTimeBase(const AVRational& time_base,
                         const base::TimeDelta& timestamp) {
   return av_rescale_q(timestamp.InMicroseconds(), kMicrosBase, time_base);
 }
 
 // Converts an FFmpeg audio codec ID into its corresponding supported codec id.
 static AudioCodec CodecIDToAudioCodec(AVCodecID codec_id) {
   switch (codec_id) {
     case AV_CODEC_ID_AAC:
       return kCodecAAC;
+#if defined(ENABLE_AC3_EAC3_AUDIO_DEMUXING)
+    case AV_CODEC_ID_AC3:
+      return kCodecAC3;
+    case AV_CODEC_ID_EAC3:
+      return kCodecEAC3;
+#endif
     case AV_CODEC_ID_MP3:
       return kCodecMP3;
     case AV_CODEC_ID_VORBIS:
       return kCodecVorbis;
     case AV_CODEC_ID_PCM_U8:
     case AV_CODEC_ID_PCM_S16LE:
     case AV_CODEC_ID_PCM_S24LE:
     case AV_CODEC_ID_PCM_F32LE:
       return kCodecPCM;
     case AV_CODEC_ID_PCM_S16BE:
@@ skipping 194 matching lines @@
 
 void AVCodecContextToAudioDecoderConfig(
     const AVCodecContext* codec_context,
     bool is_encrypted,
     AudioDecoderConfig* config,
     bool record_stats) {
   DCHECK_EQ(codec_context->codec_type, AVMEDIA_TYPE_AUDIO);
 
   AudioCodec codec = CodecIDToAudioCodec(codec_context->codec_id);
 
+  // For AC3/EAC3, FFmpeg does not fill |sample_fmt|.
   SampleFormat sample_format =
-      AVSampleFormatToSampleFormat(codec_context->sample_fmt);
+      (codec == kCodecAC3 || codec == kCodecEAC3)
+      ? kSampleFormatS16
+      : AVSampleFormatToSampleFormat(codec_context->sample_fmt);
 
   ChannelLayout channel_layout = ChannelLayoutToChromeChannelLayout(
       codec_context->channel_layout, codec_context->channels);
 
   int sample_rate = codec_context->sample_rate;
   if (codec == kCodecOpus) {
     // |codec_context->sample_fmt| is not set by FFmpeg because Opus decoding is
     // not enabled in FFmpeg.  It doesn't matter what value is set here, so long
     // as it's valid, the true sample format is selected inside the decoder.
     sample_format = kSampleFormatF32;
@@ skipping 15 matching lines @@
   config->Initialize(codec,
                      sample_format,
                      channel_layout,
                      sample_rate,
                      codec_context->extradata,
                      codec_context->extradata_size,
                      is_encrypted,
                      record_stats,
                      seek_preroll,
                      codec_context->delay);
-  if (codec != kCodecOpus) {
+  if (codec != kCodecOpus && codec != kCodecAC3 && codec != kCodecEAC3) {
     DCHECK_EQ(av_get_bytes_per_sample(codec_context->sample_fmt) * 8,
               config->bits_per_channel());
   }
 }
 
 void AVStreamToAudioDecoderConfig(
     const AVStream* stream,
     AudioDecoderConfig* config,
     bool record_stats) {
   bool is_encrypted = false;
@@ skipping 256 matching lines @@
       return false;
 
     *out = parsed_time;
     return true;
   }
 
   return false;
 }
 
 }  // namespace media