1/* 2 * Copyright (C) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29#include "config.h" 30 31#if ENABLE(WEB_AUDIO) 32 33#include "platform/audio/ReverbConvolverStage.h" 34 35#include "platform/audio/ReverbAccumulationBuffer.h" 36#include "platform/audio/ReverbConvolver.h" 37#include "platform/audio/ReverbInputBuffer.h" 38#include "platform/audio/VectorMath.h" 39#include "wtf/PassOwnPtr.h" 40 41namespace blink { 42 43using namespace VectorMath; 44 45ReverbConvolverStage::ReverbConvolverStage(const float* impulseResponse, size_t, size_t reverbTotalLatency, size_t stageOffset, size_t stageLength, 46 size_t fftSize, size_t renderPhase, size_t renderSliceSize, ReverbAccumulationBuffer* accumulationBuffer, bool directMode) 47 : m_accumulationBuffer(accumulationBuffer) 48 , m_accumulationReadIndex(0) 49 , m_inputReadIndex(0) 50 , m_directMode(directMode) 51{ 52 ASSERT(impulseResponse); 53 ASSERT(accumulationBuffer); 54 55 if (!m_directMode) { 56 m_fftKernel = adoptPtr(new FFTFrame(fftSize)); 57 m_fftKernel->doPaddedFFT(impulseResponse + stageOffset, stageLength); 58 m_fftConvolver = adoptPtr(new FFTConvolver(fftSize)); 59 } else { 60 ASSERT(!stageOffset); 61 ASSERT(stageLength <= fftSize / 2); 62 63 m_directKernel = adoptPtr(new AudioFloatArray(fftSize / 2)); 64 m_directKernel->copyToRange(impulseResponse, 0, stageLength); 65 m_directConvolver = adoptPtr(new DirectConvolver(renderSliceSize)); 66 } 67 m_temporaryBuffer.allocate(renderSliceSize); 68 69 // The convolution stage at offset stageOffset needs to have a corresponding delay to cancel out the offset. 70 size_t totalDelay = stageOffset + reverbTotalLatency; 71 72 // But, the FFT convolution itself incurs fftSize / 2 latency, so subtract this out... 73 size_t halfSize = fftSize / 2; 74 if (!m_directMode) { 75 ASSERT(totalDelay >= halfSize); 76 if (totalDelay >= halfSize) 77 totalDelay -= halfSize; 78 } 79 80 // We divide up the total delay, into pre and post delay sections so that we can schedule at exactly the moment when the FFT will happen. 81 // This is coordinated with the other stages, so they don't all do their FFTs at the same time... 82 int maxPreDelayLength = std::min(halfSize, totalDelay); 83 m_preDelayLength = totalDelay > 0 ? renderPhase % maxPreDelayLength : 0; 84 if (m_preDelayLength > totalDelay) 85 m_preDelayLength = 0; 86 87 m_postDelayLength = totalDelay - m_preDelayLength; 88 m_preReadWriteIndex = 0; 89 m_framesProcessed = 0; // total frames processed so far 90 91 size_t delayBufferSize = m_preDelayLength < fftSize ? fftSize : m_preDelayLength; 92 delayBufferSize = delayBufferSize < renderSliceSize ? renderSliceSize : delayBufferSize; 93 m_preDelayBuffer.allocate(delayBufferSize); 94} 95 96void ReverbConvolverStage::processInBackground(ReverbConvolver* convolver, size_t framesToProcess) 97{ 98 ReverbInputBuffer* inputBuffer = convolver->inputBuffer(); 99 float* source = inputBuffer->directReadFrom(&m_inputReadIndex, framesToProcess); 100 process(source, framesToProcess); 101} 102 103void ReverbConvolverStage::process(const float* source, size_t framesToProcess) 104{ 105 ASSERT(source); 106 if (!source) 107 return; 108 109 // Deal with pre-delay stream : note special handling of zero delay. 110 111 const float* preDelayedSource; 112 float* preDelayedDestination; 113 float* temporaryBuffer; 114 bool isTemporaryBufferSafe = false; 115 if (m_preDelayLength > 0) { 116 // Handles both the read case (call to process() ) and the write case (memcpy() ) 117 bool isPreDelaySafe = m_preReadWriteIndex + framesToProcess <= m_preDelayBuffer.size(); 118 ASSERT(isPreDelaySafe); 119 if (!isPreDelaySafe) 120 return; 121 122 isTemporaryBufferSafe = framesToProcess <= m_temporaryBuffer.size(); 123 124 preDelayedDestination = m_preDelayBuffer.data() + m_preReadWriteIndex; 125 preDelayedSource = preDelayedDestination; 126 temporaryBuffer = m_temporaryBuffer.data(); 127 } else { 128 // Zero delay 129 preDelayedDestination = 0; 130 preDelayedSource = source; 131 temporaryBuffer = m_preDelayBuffer.data(); 132 133 isTemporaryBufferSafe = framesToProcess <= m_preDelayBuffer.size(); 134 } 135 136 ASSERT(isTemporaryBufferSafe); 137 if (!isTemporaryBufferSafe) 138 return; 139 140 if (m_framesProcessed < m_preDelayLength) { 141 // For the first m_preDelayLength frames don't process the convolver, instead simply buffer in the pre-delay. 142 // But while buffering the pre-delay, we still need to update our index. 143 m_accumulationBuffer->updateReadIndex(&m_accumulationReadIndex, framesToProcess); 144 } else { 145 // Now, run the convolution (into the delay buffer). 146 // An expensive FFT will happen every fftSize / 2 frames. 147 // We process in-place here... 148 if (!m_directMode) 149 m_fftConvolver->process(m_fftKernel.get(), preDelayedSource, temporaryBuffer, framesToProcess); 150 else 151 m_directConvolver->process(m_directKernel.get(), preDelayedSource, temporaryBuffer, framesToProcess); 152 153 // Now accumulate into reverb's accumulation buffer. 154 m_accumulationBuffer->accumulate(temporaryBuffer, framesToProcess, &m_accumulationReadIndex, m_postDelayLength); 155 } 156 157 // Finally copy input to pre-delay. 158 if (m_preDelayLength > 0) { 159 memcpy(preDelayedDestination, source, sizeof(float) * framesToProcess); 160 m_preReadWriteIndex += framesToProcess; 161 162 ASSERT(m_preReadWriteIndex <= m_preDelayLength); 163 if (m_preReadWriteIndex >= m_preDelayLength) 164 m_preReadWriteIndex = 0; 165 } 166 167 m_framesProcessed += framesToProcess; 168} 169 170void ReverbConvolverStage::reset() 171{ 172 if (!m_directMode) 173 m_fftConvolver->reset(); 174 else 175 m_directConvolver->reset(); 176 m_preDelayBuffer.zero(); 177 m_accumulationReadIndex = 0; 178 m_inputReadIndex = 0; 179 m_framesProcessed = 0; 180} 181 182} // namespace blink 183 184#endif // ENABLE(WEB_AUDIO) 185