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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 "ReverbConvolverStage.h"
#include "ReverbAccumulationBuffer.h"
#include "ReverbConvolver.h"
#include "ReverbInputBuffer.h"
#include "mozilla/PodOperations.h"
using namespace mozilla;
namespace WebCore {
ReverbConvolverStage::ReverbConvolverStage(
const float* impulseResponse, size_t, size_t reverbTotalLatency,
size_t stageOffset, size_t stageLength, size_t fftSize, size_t renderPhase,
ReverbAccumulationBuffer* accumulationBuffer)
: m_accumulationBuffer(accumulationBuffer),
m_accumulationReadIndex(0),
m_inputReadIndex(0) {
MOZ_ASSERT(impulseResponse);
MOZ_ASSERT(accumulationBuffer);
m_fftKernel = MakeUnique<FFTBlock>(fftSize);
m_fftKernel->PadAndMakeScaledDFT(impulseResponse + stageOffset, stageLength);
m_fftConvolver = MakeUnique<FFTConvolver>(fftSize, renderPhase);
// The convolution stage at offset stageOffset needs to have a corresponding
// delay to cancel out the offset.
size_t totalDelay = stageOffset + reverbTotalLatency;
// But, the FFT convolution itself incurs latency, so subtract this out...
size_t fftLatency = m_fftConvolver->latencyFrames();
MOZ_ASSERT(totalDelay >= fftLatency);
totalDelay -= fftLatency;
m_postDelayLength = totalDelay;
}
size_t ReverbConvolverStage::sizeOfIncludingThis(
mozilla::MallocSizeOf aMallocSizeOf) const {
size_t amount = aMallocSizeOf(this);
if (m_fftKernel) {
amount += m_fftKernel->SizeOfIncludingThis(aMallocSizeOf);
}
if (m_fftConvolver) {
amount += m_fftConvolver->sizeOfIncludingThis(aMallocSizeOf);
}
return amount;
}
void ReverbConvolverStage::processInBackground(ReverbConvolver* convolver) {
ReverbInputBuffer* inputBuffer = convolver->inputBuffer();
float* source =
inputBuffer->directReadFrom(&m_inputReadIndex, WEBAUDIO_BLOCK_SIZE);
process(source);
}
void ReverbConvolverStage::process(const float* source) {
MOZ_ASSERT(source);
if (!source) return;
// Now, run the convolution (into the delay buffer).
// An expensive FFT will happen every fftSize / 2 frames.
const float* output = m_fftConvolver->process(m_fftKernel.get(), source);
// Now accumulate into reverb's accumulation buffer.
m_accumulationBuffer->accumulate(output, WEBAUDIO_BLOCK_SIZE,
&m_accumulationReadIndex, m_postDelayLength);
}
} // namespace WebCore