gecko/content/media/webaudio/ChannelMergerNode.cpp

80 lines
2.5 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 "mozilla/dom/ChannelMergerNode.h"
#include "mozilla/dom/ChannelMergerNodeBinding.h"
#include "AudioNodeEngine.h"
#include "AudioNodeStream.h"
#include "mozilla/PodOperations.h"
namespace mozilla {
namespace dom {
NS_IMPL_ISUPPORTS_INHERITED0(ChannelMergerNode, AudioNode)
class ChannelMergerNodeEngine : public AudioNodeEngine
{
public:
ChannelMergerNodeEngine(ChannelMergerNode* aNode)
: AudioNodeEngine(aNode)
{
MOZ_ASSERT(NS_IsMainThread());
}
virtual void ProduceAudioBlocksOnPorts(AudioNodeStream* aStream,
const OutputChunks& aInput,
OutputChunks& aOutput,
bool* aFinished) MOZ_OVERRIDE
{
MOZ_ASSERT(aInput.Length() >= 1, "Should have one or more input ports");
// Get the number of output channels, and allocate it
uint32_t channelCount = 0;
for (uint16_t i = 0; i < InputCount(); ++i) {
channelCount += aInput[i].mChannelData.Length();
}
if (channelCount == 0) {
aOutput[0].SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
AllocateAudioBlock(channelCount, &aOutput[0]);
// Append each channel in each input to the output
uint32_t channelIndex = 0;
for (uint16_t i = 0; i < InputCount(); ++i) {
for (uint32_t j = 0; j < aInput[i].mChannelData.Length(); ++j) {
AudioBlockCopyChannelWithScale(
static_cast<const float*>(aInput[i].mChannelData[j]),
aInput[i].mVolume,
static_cast<float*>(const_cast<void*>(aOutput[0].mChannelData[channelIndex])));
++channelIndex;
}
}
}
};
ChannelMergerNode::ChannelMergerNode(AudioContext* aContext,
uint16_t aInputCount)
: AudioNode(aContext,
2,
ChannelCountMode::Max,
ChannelInterpretation::Speakers)
, mInputCount(aInputCount)
{
mStream = aContext->Graph()->CreateAudioNodeStream(new ChannelMergerNodeEngine(this),
MediaStreamGraph::INTERNAL_STREAM);
}
JSObject*
ChannelMergerNode::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aScope)
{
return ChannelMergerNodeBinding::Wrap(aCx, aScope, this);
}
}
}