gecko/content/media/webaudio/ChannelSplitterNode.cpp

72 lines
2.3 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/ChannelSplitterNode.h"
#include "mozilla/dom/ChannelSplitterNodeBinding.h"
#include "AudioNodeEngine.h"
#include "AudioNodeStream.h"
#include "mozilla/PodOperations.h"
namespace mozilla {
namespace dom {
NS_IMPL_ISUPPORTS_INHERITED0(ChannelSplitterNode, AudioNode)
class ChannelSplitterNodeEngine : public AudioNodeEngine
{
public:
ChannelSplitterNodeEngine(ChannelSplitterNode* 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 only have one input port");
aOutput.SetLength(OutputCount());
for (uint16_t i = 0; i < OutputCount(); ++i) {
if (i < aInput[0].mChannelData.Length()) {
// Split out existing channels
AllocateAudioBlock(1, &aOutput[i]);
AudioBlockCopyChannelWithScale(
static_cast<const float*>(aInput[0].mChannelData[i]),
aInput[0].mVolume,
static_cast<float*>(const_cast<void*>(aOutput[i].mChannelData[0])));
} else {
// Pad with silent channels if needed
aOutput[i].SetNull(WEBAUDIO_BLOCK_SIZE);
}
}
}
};
ChannelSplitterNode::ChannelSplitterNode(AudioContext* aContext,
uint16_t aOutputCount)
: AudioNode(aContext,
2,
ChannelCountMode::Max,
ChannelInterpretation::Speakers)
, mOutputCount(aOutputCount)
{
mStream = aContext->Graph()->CreateAudioNodeStream(new ChannelSplitterNodeEngine(this),
MediaStreamGraph::INTERNAL_STREAM);
}
JSObject*
ChannelSplitterNode::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aScope)
{
return ChannelSplitterNodeBinding::Wrap(aCx, aScope, this);
}
}
}