tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

ReverbConvolverStage.cpp (3894B)

      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 "ReverbConvolverStage.h"
     30 
     31 #include "ReverbAccumulationBuffer.h"
     32 #include "ReverbConvolver.h"
     33 #include "ReverbInputBuffer.h"
     34 
     35 using namespace mozilla;
     36 
     37 namespace WebCore {
     38 
     39 ReverbConvolverStage::ReverbConvolverStage(
     40    const float* impulseResponse, size_t, size_t reverbTotalLatency,
     41    size_t stageOffset, size_t stageLength, size_t fftSize, size_t renderPhase,
     42    ReverbAccumulationBuffer* accumulationBuffer)
     43    : m_accumulationBuffer(accumulationBuffer),
     44      m_accumulationReadIndex(0),
     45      m_inputReadIndex(0) {
     46  MOZ_ASSERT(impulseResponse);
     47  MOZ_ASSERT(accumulationBuffer);
     48 
     49  m_fftKernel = MakeUnique<FFTBlock>(fftSize);
     50  m_fftKernel->PadAndMakeScaledDFT(impulseResponse + stageOffset, stageLength);
     51  m_fftConvolver = MakeUnique<FFTConvolver>(fftSize, renderPhase);
     52 
     53  // The convolution stage at offset stageOffset needs to have a corresponding
     54  // delay to cancel out the offset.
     55  size_t totalDelay = stageOffset + reverbTotalLatency;
     56 
     57  // But, the FFT convolution itself incurs latency, so subtract this out...
     58  size_t fftLatency = m_fftConvolver->latencyFrames();
     59  MOZ_ASSERT(totalDelay >= fftLatency);
     60  totalDelay -= fftLatency;
     61 
     62  m_postDelayLength = totalDelay;
     63 }
     64 
     65 size_t ReverbConvolverStage::sizeOfIncludingThis(
     66    mozilla::MallocSizeOf aMallocSizeOf) const {
     67  size_t amount = aMallocSizeOf(this);
     68 
     69  if (m_fftKernel) {
     70    amount += m_fftKernel->SizeOfIncludingThis(aMallocSizeOf);
     71  }
     72 
     73  if (m_fftConvolver) {
     74    amount += m_fftConvolver->sizeOfIncludingThis(aMallocSizeOf);
     75  }
     76 
     77  return amount;
     78 }
     79 
     80 void ReverbConvolverStage::processInBackground(ReverbConvolver* convolver) {
     81  ReverbInputBuffer* inputBuffer = convolver->inputBuffer();
     82  float* source =
     83      inputBuffer->directReadFrom(&m_inputReadIndex, WEBAUDIO_BLOCK_SIZE);
     84  process(source);
     85 }
     86 
     87 void ReverbConvolverStage::process(const float* source) {
     88  MOZ_ASSERT(source);
     89  if (!source) return;
     90 
     91  // Now, run the convolution (into the delay buffer).
     92  // An expensive FFT will happen every fftSize / 2 frames.
     93  const float* output = m_fftConvolver->process(m_fftKernel.get(), source);
     94 
     95  // Now accumulate into reverb's accumulation buffer.
     96  m_accumulationBuffer->accumulate(output, WEBAUDIO_BLOCK_SIZE,
     97                                   &m_accumulationReadIndex, m_postDelayLength);
     98 }
     99 
    100 }  // namespace WebCore