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// 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 "content/renderer/media/renderer_webaudiodevice_impl.h"
#include "base/command_line.h"
#include "base/logging.h"
#include "base/single_thread_task_runner.h"
#include "base/thread_task_runner_handle.h"
#include "base/time/time.h"
#include "content/renderer/media/audio_device_factory.h"
#include "content/renderer/render_frame_impl.h"
#include "media/audio/audio_output_device.h"
#include "media/audio/null_audio_sink.h"
#include "media/base/media_switches.h"
#include "third_party/WebKit/public/web/WebLocalFrame.h"
#include "third_party/WebKit/public/web/WebView.h"
using blink::WebAudioDevice;
using blink::WebLocalFrame;
using blink::WebVector;
using blink::WebView;
namespace content {
#if defined(OS_ANDROID)
static const int kSilenceInSecondsToEnterIdleMode = 30;
#endif
RendererWebAudioDeviceImpl::RendererWebAudioDeviceImpl(
const media::AudioParameters& params,
WebAudioDevice::RenderCallback* callback,
int session_id)
: params_(params),
client_callback_(callback),
session_id_(session_id),
task_runner_(base::ThreadTaskRunnerHandle::Get()),
null_audio_sink_(new media::NullAudioSink(task_runner_)),
is_using_null_audio_sink_(false),
first_buffer_after_silence_(media::AudioBus::Create(params_)),
is_first_buffer_after_silence_(false) {
DCHECK(client_callback_);
null_audio_sink_->Initialize(params_, this);
}
RendererWebAudioDeviceImpl::~RendererWebAudioDeviceImpl() {
DCHECK(!output_device_);
}
void RendererWebAudioDeviceImpl::start() {
DCHECK(thread_checker_.CalledOnValidThread());
if (output_device_)
return; // Already started.
// Assumption: This method is being invoked within a V8 call stack. CHECKs
// will fail in the call to frameForCurrentContext() otherwise.
//
// Therefore, we can perform look-ups to determine which RenderView is
// starting the audio device. The reason for all this is because the creator
// of the WebAudio objects might not be the actual source of the audio (e.g.,
// an extension creates a object that is passed and used within a page).
WebLocalFrame* const web_frame = WebLocalFrame::frameForCurrentContext();
RenderFrame* const render_frame =
web_frame ? RenderFrame::FromWebFrame(web_frame) : NULL;
output_device_ = AudioDeviceFactory::NewOutputDevice(
render_frame ? render_frame->GetRoutingID(): MSG_ROUTING_NONE);
output_device_->InitializeWithSessionId(params_, this, session_id_);
output_device_->Start();
start_null_audio_sink_callback_.Reset(
base::Bind(&media::NullAudioSink::Play, null_audio_sink_));
// Note: Default behavior is to auto-play on start.
}
void RendererWebAudioDeviceImpl::stop() {
DCHECK(thread_checker_.CalledOnValidThread());
if (output_device_) {
output_device_->Stop();
output_device_ = NULL;
}
null_audio_sink_->Stop();
is_using_null_audio_sink_ = false;
is_first_buffer_after_silence_ = false;
start_null_audio_sink_callback_.Cancel();
}
double RendererWebAudioDeviceImpl::sampleRate() {
return params_.sample_rate();
}
int RendererWebAudioDeviceImpl::Render(media::AudioBus* dest,
int audio_delay_milliseconds) {
#if defined(OS_ANDROID)
if (is_first_buffer_after_silence_) {
DCHECK(!is_using_null_audio_sink_);
first_buffer_after_silence_->CopyTo(dest);
is_first_buffer_after_silence_ = false;
return dest->frames();
}
#endif
// Wrap the output pointers using WebVector.
WebVector<float*> web_audio_dest_data(
static_cast<size_t>(dest->channels()));
for (int i = 0; i < dest->channels(); ++i)
web_audio_dest_data[i] = dest->channel(i);
// TODO(xians): Remove the following |web_audio_source_data| after
// changing the blink interface.
WebVector<float*> web_audio_source_data(static_cast<size_t>(0));
client_callback_->render(web_audio_source_data,
web_audio_dest_data,
dest->frames());
#if defined(OS_ANDROID)
const bool is_zero = dest->AreFramesZero();
if (!is_zero) {
first_silence_time_ = base::TimeTicks();
if (is_using_null_audio_sink_) {
// This is called on the main render thread when audio is detected.
output_device_->Play();
is_using_null_audio_sink_ = false;
is_first_buffer_after_silence_ = true;
dest->CopyTo(first_buffer_after_silence_.get());
task_runner_->PostTask(
FROM_HERE,
base::Bind(&media::NullAudioSink::Stop, null_audio_sink_));
}
} else if (!is_using_null_audio_sink_) {
// Called on the audio device thread.
const base::TimeTicks now = base::TimeTicks::Now();
if (first_silence_time_.is_null())
first_silence_time_ = now;
if (now - first_silence_time_
> base::TimeDelta::FromSeconds(kSilenceInSecondsToEnterIdleMode)) {
output_device_->Pause();
is_using_null_audio_sink_ = true;
// If Stop() is called right after the task is posted, need to cancel
// this task.
task_runner_->PostDelayedTask(
FROM_HERE,
start_null_audio_sink_callback_.callback(),
params_.GetBufferDuration());
}
}
#endif
return dest->frames();
}
void RendererWebAudioDeviceImpl::OnRenderError() {
// TODO(crogers): implement error handling.
}
} // namespace content
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