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/*
* Copyright (C) 2010 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#if ENABLE(WEB_AUDIO)
#include "AudioChannelSplitter.h"
#include "AudioNodeInput.h"
#include "AudioNodeOutput.h"
namespace WebCore {
// This is considering that 5.1 (6 channels) is the largest we'll ever deal with.
// It can easily be increased to support more if the web audio specification is updated.
const unsigned NumberOfOutputs = 6;
AudioChannelSplitter::AudioChannelSplitter(AudioContext* context, double sampleRate)
: AudioNode(context, sampleRate)
{
addInput(adoptPtr(new AudioNodeInput(this)));
// Create a fixed number of outputs (able to handle the maximum number of channels fed to an input).
for (unsigned i = 0; i < NumberOfOutputs; ++i)
addOutput(adoptPtr(new AudioNodeOutput(this, 1)));
setType(NodeTypeChannelSplitter);
initialize();
}
void AudioChannelSplitter::process(size_t framesToProcess)
{
AudioBus* source = input(0)->bus();
ASSERT(source);
ASSERT_UNUSED(framesToProcess, framesToProcess == source->length());
unsigned numberOfSourceChannels = source->numberOfChannels();
ASSERT(numberOfOutputs() == NumberOfOutputs);
for (unsigned i = 0; i < NumberOfOutputs; ++i) {
AudioBus* destination = output(i)->bus();
ASSERT(destination);
if (i < numberOfSourceChannels) {
// Split the channel out if it exists in the source.
// It would be nice to avoid the copy and simply pass along pointers, but this becomes extremely difficult with fanout and fanin.
destination->channel(0)->copyFrom(source->channel(i));
} else if (output(i)->fanOutCount() > 0) {
// Only bother zeroing out the destination if it's connected to anything
destination->zero();
}
}
}
void AudioChannelSplitter::reset()
{
}
} // namespace WebCore
#endif // ENABLE(WEB_AUDIO)
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