| // 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, |
| const char* data, size_t data_size, double sample_rate) { |
| DCHECK(destination_bus); |
| if (!destination_bus) |
| return false; |
| |
| // Uses the FFmpeg library for audio file reading. |
| InMemoryUrlProtocol url_protocol(reinterpret_cast<const uint8*>(data), |
| data_size, false); |
| AudioFileReader reader(&url_protocol); |
| |
| if (!reader.Open()) |
| return false; |
| |
| size_t number_of_channels = reader.channels(); |
| double file_sample_rate = reader.sample_rate(); |
| double duration = reader.duration().InSecondsF(); |
| 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; |
| |
| 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; |
| |
| // Allocate and configure the output audio channel data. |
| destination_bus->initialize(number_of_channels, |
| number_of_frames, |
| 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_bus.get()); |
| } |
| |
| } // namespace webkit_media |