gecko/content/media/nsAudioAvailableEventManager.cpp

218 lines
7.7 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: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla code.
*
* The Initial Developer of the Original Code is the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* David Humphrey <david.humphrey@senecac.on.ca>
* Yury Delendik
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsTArray.h"
#include "nsAudioAvailableEventManager.h"
#define MILLISECONDS_PER_SECOND 1000
#define MAX_PENDING_EVENTS 100
using namespace mozilla;
class nsAudioAvailableEventRunner : public nsRunnable
{
private:
nsCOMPtr<nsBuiltinDecoder> mDecoder;
nsAutoArrayPtr<float> mFrameBuffer;
public:
nsAudioAvailableEventRunner(nsBuiltinDecoder* aDecoder, float* aFrameBuffer,
PRUint32 aFrameBufferLength, PRUint64 aTime) :
mDecoder(aDecoder),
mFrameBuffer(aFrameBuffer),
mFrameBufferLength(aFrameBufferLength),
mTime(aTime)
{
}
NS_IMETHOD Run()
{
mDecoder->AudioAvailable(mFrameBuffer.forget(), mFrameBufferLength, mTime);
return NS_OK;
}
const PRUint32 mFrameBufferLength;
const PRUint64 mTime;
};
nsAudioAvailableEventManager::nsAudioAvailableEventManager(nsBuiltinDecoder* aDecoder) :
mDecoder(aDecoder),
mSignalBuffer(new float[mDecoder->GetFrameBufferLength()]),
mSignalBufferLength(mDecoder->GetFrameBufferLength()),
mSignalBufferPosition(0),
mMonitor("media.audioavailableeventmanager")
{
}
void nsAudioAvailableEventManager::Init(PRUint32 aChannels, PRUint32 aRate)
{
NS_ASSERTION(aChannels != 0 && aRate != 0, "Audio metadata not known.");
mSamplesPerSecond = aChannels * aRate;
}
void nsAudioAvailableEventManager::DispatchPendingEvents(PRUint64 aCurrentTime)
{
MonitorAutoEnter mon(mMonitor);
while (mPendingEvents.Length() > 0) {
nsAudioAvailableEventRunner* e =
(nsAudioAvailableEventRunner*)mPendingEvents[0].get();
if (e->mTime > aCurrentTime) {
break;
}
nsCOMPtr<nsIRunnable> event = mPendingEvents[0];
mPendingEvents.RemoveElementAt(0);
NS_DispatchToMainThread(event, NS_DISPATCH_NORMAL);
}
}
void nsAudioAvailableEventManager::QueueWrittenAudioData(float* aAudioData,
PRUint32 aAudioDataLength,
PRUint64 aEndTimeSampleOffset)
{
PRUint32 currentBufferSize = mDecoder->GetFrameBufferLength();
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;
}
float* audioData = aAudioData;
PRUint32 audioDataLength = aAudioDataLength;
PRUint32 signalBufferTail = mSignalBufferLength - mSignalBufferPosition;
// Group audio samples into optimal size for event dispatch, and queue.
while (signalBufferTail <= audioDataLength) {
PRUint64 time = 0;
// Guard against unsigned number overflow during first frame time calculation.
if (aEndTimeSampleOffset > mSignalBufferPosition + audioDataLength) {
time = MILLISECONDS_PER_SECOND * (aEndTimeSampleOffset -
mSignalBufferPosition - audioDataLength) / mSamplesPerSecond;
}
// Fill the signalBuffer.
memcpy(mSignalBuffer.get() + mSignalBufferPosition,
audioData, sizeof(float) * signalBufferTail);
audioData += signalBufferTail;
audioDataLength -= signalBufferTail;
MonitorAutoEnter mon(mMonitor);
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 sound 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(audioDataLength >= 0, "Past new signal data length.");
}
NS_ASSERTION(mSignalBufferPosition + audioDataLength < mSignalBufferLength,
"Intermediate signal buffer must fit at least one more item.");
if (audioDataLength > 0) {
// Add data to the signalBuffer.
memcpy(mSignalBuffer.get() + mSignalBufferPosition,
audioData, sizeof(float) * audioDataLength);
mSignalBufferPosition += audioDataLength;
}
}
void nsAudioAvailableEventManager::Clear()
{
MonitorAutoEnter mon(mMonitor);
mPendingEvents.Clear();
mSignalBufferPosition = 0;
}
void nsAudioAvailableEventManager::Drain(PRUint64 aEndTime)
{
MonitorAutoEnter mon(mMonitor);
// Force all pending events to go now.
for (PRUint32 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.
nsCOMPtr<nsIRunnable> lastEvent =
new nsAudioAvailableEventRunner(mDecoder, mSignalBuffer.forget(),
mSignalBufferLength, aEndTime);
NS_DispatchToMainThread(lastEvent, NS_DISPATCH_NORMAL);
mSignalBufferPosition = 0;
}