1 // Copyright 2019 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "third_party/blink/renderer/platform/audio/media_multi_channel_resampler.h"
6
7 #include <memory>
8 #include "base/bind.h"
9 #include "media/base/audio_bus.h"
10 #include "third_party/blink/renderer/platform/audio/audio_bus.h"
11
12 namespace blink {
13
MediaMultiChannelResampler(int channels,double io_sample_rate_ratio,size_t request_frames,ReadCB read_cb)14 MediaMultiChannelResampler::MediaMultiChannelResampler(
15 int channels,
16 double io_sample_rate_ratio,
17 size_t request_frames,
18 ReadCB read_cb)
19 : read_cb_(std::move(read_cb)) {
20 resampler_.reset(new media::MultiChannelResampler(
21 channels, io_sample_rate_ratio, request_frames,
22 base::BindRepeating(&MediaMultiChannelResampler::ProvideResamplerInput,
23 base::Unretained(this))));
24 }
25
Resample(int frames,blink::AudioBus * audio_bus)26 void MediaMultiChannelResampler::Resample(int frames,
27 blink::AudioBus* audio_bus) {
28 // Create a media::AudioBus wrapper around the memory provided by the
29 // blink::AudioBus.
30 std::unique_ptr<media::AudioBus> resampler_bus_ =
31 media::AudioBus::CreateWrapper(audio_bus->NumberOfChannels());
32 for (unsigned int i = 0; i < audio_bus->NumberOfChannels(); ++i) {
33 resampler_bus_->SetChannelData(i, audio_bus->Channel(i)->MutableData());
34 }
35 resampler_bus_->set_frames(audio_bus->length());
36 ResampleInternal(frames, resampler_bus_.get());
37 }
38
ResampleInternal(int frames,media::AudioBus * audio_bus)39 void MediaMultiChannelResampler::ResampleInternal(int frames,
40 media::AudioBus* audio_bus) {
41 resampler_->Resample(frames, audio_bus);
42 }
43
ProvideResamplerInput(int resampler_frame_delay,media::AudioBus * dest)44 void MediaMultiChannelResampler::ProvideResamplerInput(
45 int resampler_frame_delay,
46 media::AudioBus* dest) {
47 // Create a blink::AudioBus wrapper around the memory provided by the
48 // media::AudioBus.
49 scoped_refptr<AudioBus> bus =
50 AudioBus::Create(dest->channels(), dest->frames(), false);
51 for (int i = 0; i < dest->channels(); ++i) {
52 bus->SetChannelMemory(i, dest->channel(i), dest->frames());
53 }
54 read_cb_.Run(resampler_frame_delay, bus.get());
55 }
56
57 } // namespace blink
58