The Tor Browser: comparison content/media/webaudio/blink/HRTFPanner.cpp

--1:000000000000
+:1de3d4407b8a
+/*
+* 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.
+*
+* THIS SOFTWARE IS PROVIDED BY APPLE INC. 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 INC. 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 "HRTFPanner.h"
+#include "HRTFDatabaseLoader.h"
+#include "FFTConvolver.h"
+#include "HRTFDatabase.h"
+using namespace std;
+using namespace mozilla;
+using dom::ChannelInterpretation;
+namespace WebCore {
+// The value of 2 milliseconds is larger than the largest delay which exists in any HRTFKernel from the default HRTFDatabase (0.0136 seconds).
+// We ASSERT the delay values used in process() with this value.
+const double MaxDelayTimeSeconds = 0.002;
+const int UninitializedAzimuth = -1;
+const unsigned RenderingQuantum = WEBAUDIO_BLOCK_SIZE;
+HRTFPanner::HRTFPanner(float sampleRate, mozilla::TemporaryRef<HRTFDatabaseLoader> databaseLoader)
+: m_databaseLoader(databaseLoader)
+, m_sampleRate(sampleRate)
+, m_crossfadeSelection(CrossfadeSelection1)
+, m_azimuthIndex1(UninitializedAzimuth)
+, m_azimuthIndex2(UninitializedAzimuth)
+// m_elevation1 and m_elevation2 are initialized in pan()
+, m_crossfadeX(0)
+, m_crossfadeIncr(0)
+, m_convolverL1(HRTFElevation::fftSizeForSampleRate(sampleRate))
+, m_convolverR1(m_convolverL1.fftSize())
+, m_convolverL2(m_convolverL1.fftSize())
+, m_convolverR2(m_convolverL1.fftSize())
+, m_delayLine(MaxDelayTimeSeconds * sampleRate, 1.0)
+{
+MOZ_ASSERT(m_databaseLoader);
+MOZ_COUNT_CTOR(HRTFPanner);
+m_tempL1.SetLength(RenderingQuantum);
+m_tempR1.SetLength(RenderingQuantum);
+m_tempL2.SetLength(RenderingQuantum);
+m_tempR2.SetLength(RenderingQuantum);
+}
+HRTFPanner::~HRTFPanner()
+{
+MOZ_COUNT_DTOR(HRTFPanner);
+}
+size_t HRTFPanner::sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
+{
+size_t amount = aMallocSizeOf(this);
+if (m_databaseLoader) {
+m_databaseLoader->sizeOfIncludingThis(aMallocSizeOf);
+}
+amount += m_convolverL1.sizeOfExcludingThis(aMallocSizeOf);
+amount += m_convolverR1.sizeOfExcludingThis(aMallocSizeOf);
+amount += m_convolverL2.sizeOfExcludingThis(aMallocSizeOf);
+amount += m_convolverR2.sizeOfExcludingThis(aMallocSizeOf);
+amount += m_delayLine.SizeOfExcludingThis(aMallocSizeOf);
+amount += m_tempL1.SizeOfExcludingThis(aMallocSizeOf);
+amount += m_tempL2.SizeOfExcludingThis(aMallocSizeOf);
+amount += m_tempR1.SizeOfExcludingThis(aMallocSizeOf);
+amount += m_tempR2.SizeOfExcludingThis(aMallocSizeOf);
+return amount;
+}
+void HRTFPanner::reset()
+{
+m_azimuthIndex1 = UninitializedAzimuth;
+m_azimuthIndex2 = UninitializedAzimuth;
+// m_elevation1 and m_elevation2 are initialized in pan()
+m_crossfadeSelection = CrossfadeSelection1;
+m_crossfadeX = 0.0f;
+m_crossfadeIncr = 0.0f;
+m_convolverL1.reset();
+m_convolverR1.reset();
+m_convolverL2.reset();
+m_convolverR2.reset();
+m_delayLine.Reset();
+}
+int HRTFPanner::calculateDesiredAzimuthIndexAndBlend(double azimuth, double& azimuthBlend)
+{
+// Convert the azimuth angle from the range -180 -> +180 into the range 0 -> 360.
+// The azimuth index may then be calculated from this positive value.
+if (azimuth < 0)
+azimuth += 360.0;
+HRTFDatabase* database = m_databaseLoader->database();
+MOZ_ASSERT(database);
+int numberOfAzimuths = database->numberOfAzimuths();
+const double angleBetweenAzimuths = 360.0 / numberOfAzimuths;
+// Calculate the azimuth index and the blend (0 -> 1) for interpolation.
+double desiredAzimuthIndexFloat = azimuth / angleBetweenAzimuths;
+int desiredAzimuthIndex = static_cast<int>(desiredAzimuthIndexFloat);
+azimuthBlend = desiredAzimuthIndexFloat - static_cast<double>(desiredAzimuthIndex);
+// We don't immediately start using this azimuth index, but instead approach this index from the last index we rendered at.
+// This minimizes the clicks and graininess for moving sources which occur otherwise.
+desiredAzimuthIndex = max(0, desiredAzimuthIndex);
+desiredAzimuthIndex = min(numberOfAzimuths - 1, desiredAzimuthIndex);
+return desiredAzimuthIndex;
+}
+void HRTFPanner::pan(double desiredAzimuth, double elevation, const AudioChunk* inputBus, AudioChunk* outputBus)
+{
+#ifdef DEBUG
+unsigned numInputChannels =
+inputBus->IsNull() ? 0 : inputBus->mChannelData.Length();
+MOZ_ASSERT(numInputChannels <= 2);
+MOZ_ASSERT(inputBus->mDuration == WEBAUDIO_BLOCK_SIZE);
+#endif
+bool isOutputGood = outputBus && outputBus->mChannelData.Length() == 2 && outputBus->mDuration == WEBAUDIO_BLOCK_SIZE;
+MOZ_ASSERT(isOutputGood);
+if (!isOutputGood) {
+if (outputBus)
+outputBus->SetNull(outputBus->mDuration);
+return;
+}
+HRTFDatabase* database = m_databaseLoader->database();
+if (!database) { // not yet loaded
+outputBus->SetNull(outputBus->mDuration);
+return;
+}
+// IRCAM HRTF azimuths values from the loaded database is reversed from the panner's notion of azimuth.
+double azimuth = -desiredAzimuth;
+bool isAzimuthGood = azimuth >= -180.0 && azimuth <= 180.0;
+MOZ_ASSERT(isAzimuthGood);
+if (!isAzimuthGood) {
+outputBus->SetNull(outputBus->mDuration);
+return;
+}
+// Normally, we'll just be dealing with mono sources.
+// If we have a stereo input, implement stereo panning with left source processed by left HRTF, and right source by right HRTF.
+// Get destination pointers.
+float* destinationL =
+static_cast<float*>(const_cast<void*>(outputBus->mChannelData[0]));
+float* destinationR =
+static_cast<float*>(const_cast<void*>(outputBus->mChannelData[1]));
+double azimuthBlend;
+int desiredAzimuthIndex = calculateDesiredAzimuthIndexAndBlend(azimuth, azimuthBlend);
+// Initially snap azimuth and elevation values to first values encountered.
+if (m_azimuthIndex1 == UninitializedAzimuth) {
+m_azimuthIndex1 = desiredAzimuthIndex;
+m_elevation1 = elevation;
+}
+if (m_azimuthIndex2 == UninitializedAzimuth) {
+m_azimuthIndex2 = desiredAzimuthIndex;
+m_elevation2 = elevation;
+}
+// Cross-fade / transition over a period of around 45 milliseconds.
+// This is an empirical value tuned to be a reasonable trade-off between
+// smoothness and speed.
+const double fadeFrames = sampleRate() <= 48000 ? 2048 : 4096;
+// Check for azimuth and elevation changes, initiating a cross-fade if needed.
+if (!m_crossfadeX && m_crossfadeSelection == CrossfadeSelection1) {
+if (desiredAzimuthIndex != m_azimuthIndex1 || elevation != m_elevation1) {
+// Cross-fade from 1 -> 2
+m_crossfadeIncr = 1 / fadeFrames;
+m_azimuthIndex2 = desiredAzimuthIndex;
+m_elevation2 = elevation;
+}
+}
+if (m_crossfadeX == 1 && m_crossfadeSelection == CrossfadeSelection2) {
+if (desiredAzimuthIndex != m_azimuthIndex2 || elevation != m_elevation2) {
+// Cross-fade from 2 -> 1
+m_crossfadeIncr = -1 / fadeFrames;
+m_azimuthIndex1 = desiredAzimuthIndex;
+m_elevation1 = elevation;
+}
+}
+// Get the HRTFKernels and interpolated delays.
+HRTFKernel* kernelL1;
+HRTFKernel* kernelR1;
+HRTFKernel* kernelL2;
+HRTFKernel* kernelR2;
+double frameDelayL1;
+double frameDelayR1;
+double frameDelayL2;
+double frameDelayR2;
+database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex1, m_elevation1, kernelL1, kernelR1, frameDelayL1, frameDelayR1);
+database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex2, m_elevation2, kernelL2, kernelR2, frameDelayL2, frameDelayR2);
+bool areKernelsGood = kernelL1 && kernelR1 && kernelL2 && kernelR2;
+MOZ_ASSERT(areKernelsGood);
+if (!areKernelsGood) {
+outputBus->SetNull(outputBus->mDuration);
+return;
+}
+MOZ_ASSERT(frameDelayL1 / sampleRate() < MaxDelayTimeSeconds && frameDelayR1 / sampleRate() < MaxDelayTimeSeconds);
+MOZ_ASSERT(frameDelayL2 / sampleRate() < MaxDelayTimeSeconds && frameDelayR2 / sampleRate() < MaxDelayTimeSeconds);
+// Crossfade inter-aural delays based on transitions.
+double frameDelaysL[WEBAUDIO_BLOCK_SIZE];
+double frameDelaysR[WEBAUDIO_BLOCK_SIZE];
+{
+float x = m_crossfadeX;
+float incr = m_crossfadeIncr;
+for (unsigned i = 0; i < WEBAUDIO_BLOCK_SIZE; ++i) {
+frameDelaysL[i] = (1 - x) * frameDelayL1 + x * frameDelayL2;
+frameDelaysR[i] = (1 - x) * frameDelayR1 + x * frameDelayR2;
+x += incr;
+}
+}
+// First run through delay lines for inter-aural time difference.
+m_delayLine.Write(*inputBus);
+// "Speakers" means a mono input is read into both outputs (with possibly
+// different delays).
+m_delayLine.ReadChannel(frameDelaysL, outputBus, 0,
+ChannelInterpretation::Speakers);
+m_delayLine.ReadChannel(frameDelaysR, outputBus, 1,
+ChannelInterpretation::Speakers);
+m_delayLine.NextBlock();
+bool needsCrossfading = m_crossfadeIncr;
+// Have the convolvers render directly to the final destination if we're not cross-fading.
+float* convolutionDestinationL1 = needsCrossfading ? m_tempL1.Elements() : destinationL;
+float* convolutionDestinationR1 = needsCrossfading ? m_tempR1.Elements() : destinationR;
+float* convolutionDestinationL2 = needsCrossfading ? m_tempL2.Elements() : destinationL;
+float* convolutionDestinationR2 = needsCrossfading ? m_tempR2.Elements() : destinationR;
+// Now do the convolutions.
+// Note that we avoid doing convolutions on both sets of convolvers if we're not currently cross-fading.
+if (m_crossfadeSelection == CrossfadeSelection1 || needsCrossfading) {
+m_convolverL1.process(kernelL1->fftFrame(), destinationL, convolutionDestinationL1, WEBAUDIO_BLOCK_SIZE);
+m_convolverR1.process(kernelR1->fftFrame(), destinationR, convolutionDestinationR1, WEBAUDIO_BLOCK_SIZE);
+}
+if (m_crossfadeSelection == CrossfadeSelection2 || needsCrossfading) {
+m_convolverL2.process(kernelL2->fftFrame(), destinationL, convolutionDestinationL2, WEBAUDIO_BLOCK_SIZE);
+m_convolverR2.process(kernelR2->fftFrame(), destinationR, convolutionDestinationR2, WEBAUDIO_BLOCK_SIZE);
+}
+if (needsCrossfading) {
+// Apply linear cross-fade.
+float x = m_crossfadeX;
+float incr = m_crossfadeIncr;
+for (unsigned i = 0; i < WEBAUDIO_BLOCK_SIZE; ++i) {
+destinationL[i] = (1 - x) * convolutionDestinationL1[i] + x * convolutionDestinationL2[i];
+destinationR[i] = (1 - x) * convolutionDestinationR1[i] + x * convolutionDestinationR2[i];
+x += incr;
+}
+// Update cross-fade value from local.
+m_crossfadeX = x;
+if (m_crossfadeIncr > 0 && fabs(m_crossfadeX - 1) < m_crossfadeIncr) {
+// We've fully made the crossfade transition from 1 -> 2.
+m_crossfadeSelection = CrossfadeSelection2;
+m_crossfadeX = 1;
+m_crossfadeIncr = 0;
+} else if (m_crossfadeIncr < 0 && fabs(m_crossfadeX) < -m_crossfadeIncr) {
+// We've fully made the crossfade transition from 2 -> 1.
+m_crossfadeSelection = CrossfadeSelection1;
+m_crossfadeX = 0;
+m_crossfadeIncr = 0;
+}
+}
+}
+int HRTFPanner::maxTailFrames() const
+{
+// Although the ideal tail time would be the length of the impulse
+// response, there is additional tail time from the approximations in the
+// implementation.  Because HRTFPanner is implemented with a DelayKernel
+// and a FFTConvolver, the tailTime of the HRTFPanner is the sum of the
+// tailTime of the DelayKernel and the tailTime of the FFTConvolver.
+// The FFTConvolver has a tail time of fftSize(), including latency of
+// fftSize()/2.
+return m_delayLine.MaxDelayTicks() + fftSize();
+}
+} // namespace WebCore

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comparison: content/media/webaudio/blink/HRTFPanner.cpp

content/media/webaudio/blink/HRTFPanner.cpp