[Chromoting] Add AudioVolumeApplier to reduce the complexity and the dependency of kChannels
AudioVolumeApplier is a component to apply audio level to the samples, it also
has an AudioSilenceDetector internally to detect whether the samples are silent
before or after applying the level.
It does not rely on a fixed kChannels, which is good to support 5.1 / 7.1
channels.
BUG=669070
Review-Url: https://codereview.chromium.org/2840773004
Cr-Commit-Position: refs/heads/master@{#473809}
diff --git a/remoting/host/audio_capturer_win.cc b/remoting/host/audio_capturer_win.cc
index b3d4d9f..2610e6e2 100644
--- a/remoting/host/audio_capturer_win.cc
+++ b/remoting/host/audio_capturer_win.cc
@@ -45,7 +45,7 @@
AudioCapturerWin::AudioCapturerWin()
: sampling_rate_(AudioPacket::SAMPLING_RATE_INVALID),
- silence_detector_(kSilenceThreshold),
+ volume_filter_(kSilenceThreshold),
last_capture_error_(S_OK) {
thread_checker_.DetachFromThread();
}
@@ -91,14 +91,12 @@
}
audio_client_.Reset();
mm_device_.Reset();
- audio_volume_.Reset();
}
bool AudioCapturerWin::Initialize() {
DCHECK(!audio_capture_client_.Get());
DCHECK(!audio_client_.Get());
DCHECK(!mm_device_.Get());
- DCHECK(!audio_volume_.Get());
DCHECK(static_cast<PWAVEFORMATEX>(wave_format_ex_) == nullptr);
DCHECK(thread_checker_.CalledOnValidThread());
@@ -234,86 +232,15 @@
return false;
}
- // Initialize IAudioEndpointVolume.
- // TODO(zijiehe): Do we need to control per process volume?
- hr = mm_device_->Activate(__uuidof(IAudioEndpointVolume), CLSCTX_ALL, nullptr,
- &audio_volume_);
- if (FAILED(hr)) {
- LOG(ERROR) << "Failed to get an IAudioEndpointVolume. Error " << hr;
- return false;
- }
-
- silence_detector_.Reset(sampling_rate_, kChannels);
+ volume_filter_.ActivateBy(mm_device_.Get());
+ volume_filter_.Initialize(sampling_rate_, kChannels);
return true;
}
bool AudioCapturerWin::is_initialized() const {
// All Com components should be initialized / deinitialized together.
- return !!audio_volume_;
-}
-
-float AudioCapturerWin::GetAudioLevel() {
- BOOL mute;
- HRESULT hr = audio_volume_->GetMute(&mute);
- if (FAILED(hr)) {
- LOG(ERROR) << "Failed to get mute status from IAudioEndpointVolume, error "
- << hr;
- return 1;
- }
- if (mute) {
- return 0;
- }
-
- float level;
- hr = audio_volume_->GetMasterVolumeLevelScalar(&level);
- if (FAILED(hr) || level > 1) {
- LOG(ERROR) << "Failed to get master volume from IAudioEndpointVolume, "
- "error "
- << hr;
- return 1;
- }
- if (level < 0) {
- return 0;
- }
- return level;
-}
-
-void AudioCapturerWin::ProcessSamples(uint8_t* data, size_t frames) {
- if (frames == 0) {
- return;
- }
-
- int16_t* samples = reinterpret_cast<int16_t*>(data);
- static_assert(sizeof(samples[0]) == kBytesPerSample,
- "expect 16 bits per sample");
- size_t sample_count = frames * kChannels;
- if (silence_detector_.IsSilence(samples, sample_count)) {
- return;
- }
-
- // Windows API does not provide volume adjusted audio sample as Linux does.
- // So we need to manually apply volume to the samples.
- float level = GetAudioLevel();
- if (level == 0) {
- return;
- }
-
- if (level < 1) {
- int32_t level_int = static_cast<int32_t>(level * 65536);
- for (size_t i = 0; i < sample_count; i++) {
- samples[i] = (static_cast<int32_t>(samples[i]) * level_int) >> 16;
- }
- }
-
- std::unique_ptr<AudioPacket> packet(new AudioPacket());
- packet->add_data(data, frames * wave_format_ex_->nBlockAlign);
- packet->set_encoding(AudioPacket::ENCODING_RAW);
- packet->set_sampling_rate(sampling_rate_);
- packet->set_bytes_per_sample(AudioPacket::BYTES_PER_SAMPLE_2);
- packet->set_channels(AudioPacket::CHANNELS_STEREO);
-
- callback_.Run(std::move(packet));
+ return !!audio_client_;
}
void AudioCapturerWin::DoCapture() {
@@ -347,7 +274,16 @@
if (FAILED(hr))
break;
- ProcessSamples(data, frames);
+ if (volume_filter_.Apply(reinterpret_cast<int16_t*>(data), frames)) {
+ std::unique_ptr<AudioPacket> packet(new AudioPacket());
+ packet->add_data(data, frames * wave_format_ex_->nBlockAlign);
+ packet->set_encoding(AudioPacket::ENCODING_RAW);
+ packet->set_sampling_rate(sampling_rate_);
+ packet->set_bytes_per_sample(AudioPacket::BYTES_PER_SAMPLE_2);
+ packet->set_channels(AudioPacket::CHANNELS_STEREO);
+
+ callback_.Run(std::move(packet));
+ }
hr = audio_capture_client_->ReleaseBuffer(frames);
if (FAILED(hr))
