Support (E)AC3 passthrough

media/filters/decoder_stream_traits.cc

 // Copyright 2014 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/decoder_stream_traits.h"
 
 #include "base/logging.h"
 #include "media/base/audio_buffer.h"
 #include "media/base/audio_decoder.h"
 #include "media/base/audio_decoder_config.h"
+#include "media/base/media_client.h"
 #include "media/base/video_decoder.h"
 #include "media/base/video_frame.h"
 
 namespace media {
 
 std::string DecoderStreamTraits<DemuxerStream::AUDIO>::ToString() {
   return "audio";
 }
 
 void DecoderStreamTraits<DemuxerStream::AUDIO>::InitializeDecoder(
     DecoderType* decoder,
     DemuxerStream* stream,
     CdmContext* cdm_context,
     const InitCB& init_cb,
     const OutputCB& output_cb) {
   DCHECK(stream->audio_decoder_config().IsValidConfig());
-  decoder->Initialize(stream->audio_decoder_config(), cdm_context, init_cb,
-                      output_cb);
+
+  AudioDecoderConfig config = stream->audio_decoder_config();
+  AudioCodec codec = config.codec();
+  MediaClient* media_client = GetMediaClient();
+  if (media_client && media_client->IsSupportedPassthroughAudio(codec)) {
+    config.Initialize(kCodecRaw, kSampleFormatRaw, config.channel_layout(),
+                      config.samples_per_second(), config.extra_data(),
+                      config.encryption_scheme(), config.seek_preroll(),
+                      config.codec_delay());
+  }
+
+  decoder->Initialize(config, cdm_context, init_cb, output_cb);
 }
 
 bool DecoderStreamTraits<DemuxerStream::AUDIO>::NeedsBitstreamConversion(
     DecoderType* decoder) {
   return decoder->NeedsBitstreamConversion();
 }
 
 void DecoderStreamTraits<DemuxerStream::AUDIO>::ReportStatistics(
     const StatisticsCB& statistics_cb,
     int bytes_decoded) {
@@ skipping 58 matching lines @@
     const scoped_refptr<DecoderBuffer>& buffer) {
   audio_ts_validator_->CheckForTimestampGap(buffer);
 }
 
 void DecoderStreamTraits<DemuxerStream::AUDIO>::OnDecodeDone(
     const scoped_refptr<OutputType>& buffer) {
   audio_ts_validator_->RecordOutputDuration(buffer);
 }
 
 }  // namespace media