Convert WebAudio file handlers to use AudioBus.

webkit/media/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 "webkit/media/audio_decoder.h"
 
 #include <vector>
 #include "base/basictypes.h"
 #include "base/string_util.h"
 #include "base/time.h"
+#include "media/base/audio_bus.h"
 #include "media/base/limits.h"
 #include "media/filters/audio_file_reader.h"
 #include "media/filters/in_memory_url_protocol.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebAudioBus.h"
 
+using media::AudioBus;
 using media::AudioFileReader;
 using media::InMemoryUrlProtocol;
 using std::vector;
 using WebKit::WebAudioBus;
 
 namespace webkit_media {
 
 // Decode in-memory audio file data.
 bool DecodeAudioFileData(
     WebKit::WebAudioBus* destination_bus,
@@ skipping 16 matching lines @@
   size_t number_of_frames = static_cast<size_t>(reader.number_of_frames());
 
   // Apply sanity checks to make sure crazy values aren't coming out of
   // FFmpeg.
   if (!number_of_channels ||
       number_of_channels > static_cast<size_t>(media::limits::kMaxChannels) ||
       file_sample_rate < media::limits::kMinSampleRate ||
       file_sample_rate > media::limits::kMaxSampleRate)
     return false;
 
-  // TODO(crogers) : do sample-rate conversion with FFmpeg.
-  // For now, we're ignoring the requested 'sample_rate' and returning
-  // the WebAudioBus at the file's sample-rate.
-  // double destination_sample_rate =
-  //   (sample_rate != 0.0) ? sample_rate : file_sample_rate;
-  double destination_sample_rate = file_sample_rate;
-
   DVLOG(1) << "Decoding file data -"
            << " data: " << data
            << " data size: " << data_size
            << " duration: " << duration
            << " number of frames: " << number_of_frames
            << " sample rate: " << file_sample_rate
            << " number of channels: " << number_of_channels;
 
-  // Change to destination sample-rate.
-  number_of_frames = static_cast<size_t>(number_of_frames *
-      (destination_sample_rate / file_sample_rate));
-
   // Allocate and configure the output audio channel data.
   destination_bus->initialize(number_of_channels,
                               number_of_frames,
-                              destination_sample_rate);
+                              file_sample_rate);
 
   // Wrap the channel pointers which will receive the decoded PCM audio.
   vector<float*> audio_data;
   audio_data.reserve(number_of_channels);
   for (size_t i = 0; i < number_of_channels; ++i) {
     audio_data.push_back(destination_bus->channelData(i));
   }
 
+  scoped_ptr<AudioBus> audio_bus = AudioBus::WrapVector(
+      number_of_frames, audio_data);
+
   // Decode the audio file data.
-  return reader.Read(audio_data, number_of_frames);
+  return reader.Read(audio_bus.get());
 }
 
 }  // namespace webkit_media