gecko-dev/content/media/AudioAvailableEventManager.cpp

250 строки
7.8 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsTArray.h"
#include "AudioAvailableEventManager.h"
#include "VideoUtils.h"
namespace mozilla {
static const nsTArray< nsCOMPtr<nsIRunnable> >::size_type MAX_PENDING_EVENTS = 100;
class nsAudioAvailableEventRunner : public nsRunnable
{
private:
nsRefPtr<MediaDecoder> mDecoder;
nsAutoArrayPtr<float> mFrameBuffer;
public:
nsAudioAvailableEventRunner(MediaDecoder* aDecoder, float* aFrameBuffer,
uint32_t aFrameBufferLength, float aTime) :
mDecoder(aDecoder),
mFrameBuffer(aFrameBuffer),
mFrameBufferLength(aFrameBufferLength),
mTime(aTime)
{
MOZ_COUNT_CTOR(nsAudioAvailableEventRunner);
}
~nsAudioAvailableEventRunner() {
MOZ_COUNT_DTOR(nsAudioAvailableEventRunner);
}
NS_IMETHOD Run()
{
mDecoder->AudioAvailable(mFrameBuffer.forget(), mFrameBufferLength, mTime);
return NS_OK;
}
const uint32_t mFrameBufferLength;
// Start time of the buffer data (in seconds).
const float mTime;
};
AudioAvailableEventManager::AudioAvailableEventManager(MediaDecoder* aDecoder) :
mDecoder(aDecoder),
mSignalBuffer(new float[mDecoder->GetFrameBufferLength()]),
mSignalBufferLength(mDecoder->GetFrameBufferLength()),
mNewSignalBufferLength(mSignalBufferLength),
mSignalBufferPosition(0),
mReentrantMonitor("media.audioavailableeventmanager"),
mHasListener(false)
{
MOZ_COUNT_CTOR(AudioAvailableEventManager);
}
AudioAvailableEventManager::~AudioAvailableEventManager()
{
MOZ_COUNT_DTOR(AudioAvailableEventManager);
}
void AudioAvailableEventManager::Init(uint32_t aChannels, uint32_t aRate)
{
NS_ASSERTION(aChannels != 0 && aRate != 0, "Audio metadata not known.");
mSamplesPerSecond = static_cast<float>(aChannels * aRate);
}
void AudioAvailableEventManager::DispatchPendingEvents(uint64_t aCurrentTime)
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
if (!mHasListener) {
return;
}
while (mPendingEvents.Length() > 0) {
nsAudioAvailableEventRunner* e =
(nsAudioAvailableEventRunner*)mPendingEvents[0].get();
if (e->mTime * USECS_PER_S > aCurrentTime) {
break;
}
nsCOMPtr<nsIRunnable> event = mPendingEvents[0];
mPendingEvents.RemoveElementAt(0);
NS_DispatchToMainThread(event, NS_DISPATCH_NORMAL);
}
}
void AudioAvailableEventManager::QueueWrittenAudioData(AudioDataValue* aAudioData,
uint32_t aAudioDataLength,
uint64_t aEndTimeSampleOffset)
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
if (!mHasListener) {
return;
}
uint32_t currentBufferSize = mNewSignalBufferLength;
if (currentBufferSize == 0) {
NS_WARNING("Decoder framebuffer length not set.");
return;
}
if (!mSignalBuffer ||
(mSignalBufferPosition == 0 && mSignalBufferLength != currentBufferSize)) {
if (!mSignalBuffer || (mSignalBufferLength < currentBufferSize)) {
// Only resize if buffer is empty or smaller.
mSignalBuffer = new float[currentBufferSize];
}
mSignalBufferLength = currentBufferSize;
}
AudioDataValue* audioData = aAudioData;
uint32_t audioDataLength = aAudioDataLength;
uint32_t signalBufferTail = mSignalBufferLength - mSignalBufferPosition;
// Group audio samples into optimal size for event dispatch, and queue.
while (signalBufferTail <= audioDataLength) {
float time = 0.0;
// Guard against unsigned number overflow during first frame time calculation.
if (aEndTimeSampleOffset > mSignalBufferPosition + audioDataLength) {
time = (aEndTimeSampleOffset - mSignalBufferPosition - audioDataLength) /
mSamplesPerSecond;
}
// Fill the signalBuffer.
uint32_t i;
float *signalBuffer = mSignalBuffer.get() + mSignalBufferPosition;
if (audioData) {
for (i = 0; i < signalBufferTail; ++i) {
signalBuffer[i] = AudioSampleToFloat(audioData[i]);
}
} else {
memset(signalBuffer, 0, signalBufferTail*sizeof(signalBuffer[0]));
}
if (audioData) {
audioData += signalBufferTail;
}
NS_ASSERTION(audioDataLength >= signalBufferTail,
"audioDataLength about to wrap past zero to +infinity!");
audioDataLength -= signalBufferTail;
if (mPendingEvents.Length() > 0) {
// Check last event timecode to make sure that all queued events
// are in non-descending sequence.
nsAudioAvailableEventRunner* lastPendingEvent =
(nsAudioAvailableEventRunner*)mPendingEvents[mPendingEvents.Length() - 1].get();
if (lastPendingEvent->mTime > time) {
// Clear the queue to start a fresh sequence.
mPendingEvents.Clear();
} else if (mPendingEvents.Length() >= MAX_PENDING_EVENTS) {
NS_WARNING("Hit audio event queue max.");
mPendingEvents.RemoveElementsAt(0, mPendingEvents.Length() - MAX_PENDING_EVENTS + 1);
}
}
// Inform the element that we've written audio data.
nsCOMPtr<nsIRunnable> event =
new nsAudioAvailableEventRunner(mDecoder, mSignalBuffer.forget(),
mSignalBufferLength, time);
mPendingEvents.AppendElement(event);
// Reset the buffer
mSignalBufferLength = currentBufferSize;
mSignalBuffer = new float[currentBufferSize];
mSignalBufferPosition = 0;
signalBufferTail = currentBufferSize;
}
NS_ASSERTION(mSignalBufferPosition + audioDataLength < mSignalBufferLength,
"Intermediate signal buffer must fit at least one more item.");
if (audioDataLength > 0) {
// Add data to the signalBuffer.
uint32_t i;
float *signalBuffer = mSignalBuffer.get() + mSignalBufferPosition;
if (audioData) {
for (i = 0; i < audioDataLength; ++i) {
signalBuffer[i] = AudioSampleToFloat(audioData[i]);
}
} else {
memset(signalBuffer, 0, audioDataLength*sizeof(signalBuffer[0]));
}
mSignalBufferPosition += audioDataLength;
}
}
void AudioAvailableEventManager::Clear()
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
mPendingEvents.Clear();
mSignalBufferPosition = 0;
}
void AudioAvailableEventManager::Drain(uint64_t aEndTime)
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
if (!mHasListener) {
return;
}
// Force all pending events to go now.
for (uint32_t i = 0; i < mPendingEvents.Length(); ++i) {
nsCOMPtr<nsIRunnable> event = mPendingEvents[i];
NS_DispatchToMainThread(event, NS_DISPATCH_NORMAL);
}
mPendingEvents.Clear();
// If there is anything left in the signal buffer, put it in an event and fire.
if (0 == mSignalBufferPosition)
return;
// Zero-pad the end of the signal buffer so it's complete.
memset(mSignalBuffer.get() + mSignalBufferPosition, 0,
(mSignalBufferLength - mSignalBufferPosition) * sizeof(float));
// Force this last event to go now.
float time = (aEndTime / static_cast<float>(USECS_PER_S)) -
(mSignalBufferPosition / mSamplesPerSecond);
nsCOMPtr<nsIRunnable> lastEvent =
new nsAudioAvailableEventRunner(mDecoder, mSignalBuffer.forget(),
mSignalBufferLength, time);
NS_DispatchToMainThread(lastEvent, NS_DISPATCH_NORMAL);
mSignalBufferPosition = 0;
}
void AudioAvailableEventManager::SetSignalBufferLength(uint32_t aLength)
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
mNewSignalBufferLength = aLength;
}
void AudioAvailableEventManager::NotifyAudioAvailableListener()
{
ReentrantMonitorAutoEnter mon(mReentrantMonitor);
mHasListener = true;
}
} // namespace mozilla