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Diffstat (limited to 'WebCore/platform/audio/HRTFPanner.cpp')
-rw-r--r-- | WebCore/platform/audio/HRTFPanner.cpp | 229 |
1 files changed, 0 insertions, 229 deletions
diff --git a/WebCore/platform/audio/HRTFPanner.cpp b/WebCore/platform/audio/HRTFPanner.cpp deleted file mode 100644 index 68bc505..0000000 --- a/WebCore/platform/audio/HRTFPanner.cpp +++ /dev/null @@ -1,229 +0,0 @@ -/* - * 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 "config.h" - -#if ENABLE(WEB_AUDIO) - -#include "HRTFPanner.h" - -#include "AudioBus.h" -#include "FFTConvolver.h" -#include "HRTFDatabase.h" -#include "HRTFDatabaseLoader.h" -#include <algorithm> -#include <wtf/MathExtras.h> -#include <wtf/RefPtr.h> - -using namespace std; - -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; - -HRTFPanner::HRTFPanner(double sampleRate) - : Panner(PanningModelHRTF) - , m_sampleRate(sampleRate) - , m_isFirstRender(true) - , m_azimuthIndex(0) - , m_convolverL(fftSizeForSampleRate(sampleRate)) - , m_convolverR(fftSizeForSampleRate(sampleRate)) - , m_delayLineL(MaxDelayTimeSeconds, sampleRate) - , m_delayLineR(MaxDelayTimeSeconds, sampleRate) -{ -} - -HRTFPanner::~HRTFPanner() -{ -} - -size_t HRTFPanner::fftSizeForSampleRate(double sampleRate) -{ - // The HRTF impulse responses (loaded as audio resources) are 512 sample-frames @44.1KHz. - // Currently, we truncate the impulse responses to half this size, but an FFT-size of twice impulse response size is needed (for convolution). - // So for sample rates around 44.1KHz an FFT size of 512 is good. We double that size for higher sample rates. - ASSERT(sampleRate >= 44100 && sampleRate <= 96000.0); - return (sampleRate <= 48000.0) ? 512 : 1024; -} - -void HRTFPanner::reset() -{ - m_isFirstRender = true; - m_convolverL.reset(); - m_convolverR.reset(); - m_delayLineL.reset(); - m_delayLineR.reset(); -} - -static bool wrapDistance(int i, int j, int length) -{ - int directDistance = abs(i - j); - int indirectDistance = length - directDistance; - - return indirectDistance < directDistance; -} - -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 = HRTFDatabaseLoader::defaultHRTFDatabase(); - 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, AudioBus* inputBus, AudioBus* outputBus, size_t framesToProcess) -{ - unsigned numInputChannels = inputBus ? inputBus->numberOfChannels() : 0; - - bool isInputGood = inputBus && numInputChannels >= 1 && numInputChannels <= 2; - ASSERT(isInputGood); - - bool isOutputGood = outputBus && outputBus->numberOfChannels() == 2 && framesToProcess <= outputBus->length(); - ASSERT(isOutputGood); - - if (!isInputGood || !isOutputGood) { - if (outputBus) - outputBus->zero(); - return; - } - - // This code only runs as long as the context is alive and after database has been loaded. - HRTFDatabase* database = HRTFDatabaseLoader::defaultHRTFDatabase(); - ASSERT(database); - if (!database) { - outputBus->zero(); - 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; - ASSERT(isAzimuthGood); - if (!isAzimuthGood) { - outputBus->zero(); - 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. - AudioChannel* inputChannelL = inputBus->channelByType(AudioBus::ChannelLeft); - AudioChannel* inputChannelR = numInputChannels > 1 ? inputBus->channelByType(AudioBus::ChannelRight) : 0; - - // Get source and destination pointers. - float* sourceL = inputChannelL->data(); - float* sourceR = numInputChannels > 1 ? inputChannelR->data() : sourceL; - float* destinationL = outputBus->channelByType(AudioBus::ChannelLeft)->data(); - float* destinationR = outputBus->channelByType(AudioBus::ChannelRight)->data(); - - double azimuthBlend; - int desiredAzimuthIndex = calculateDesiredAzimuthIndexAndBlend(azimuth, azimuthBlend); - - // This algorithm currently requires that we process in power-of-two size chunks at least 128. - ASSERT(1UL << static_cast<int>(log2(framesToProcess)) == framesToProcess); - ASSERT(framesToProcess >= 128); - - const unsigned framesPerSegment = 128; - const unsigned numberOfSegments = framesToProcess / framesPerSegment; - - for (unsigned segment = 0; segment < numberOfSegments; ++segment) { - if (m_isFirstRender) { - // Snap exactly to desired position (first time and after reset()). - m_azimuthIndex = desiredAzimuthIndex; - m_isFirstRender = false; - } else { - // Each segment renders with an azimuth index closer by one to the desired azimuth index. - // Because inter-aural time delay is mostly a factor of azimuth and the delay is where the clicks and graininess come from, - // we don't bother smoothing the elevations. - int numberOfAzimuths = database->numberOfAzimuths(); - bool wrap = wrapDistance(m_azimuthIndex, desiredAzimuthIndex, numberOfAzimuths); - if (wrap) { - if (m_azimuthIndex < desiredAzimuthIndex) - m_azimuthIndex = (m_azimuthIndex - 1 + numberOfAzimuths) % numberOfAzimuths; - else if (m_azimuthIndex > desiredAzimuthIndex) - m_azimuthIndex = (m_azimuthIndex + 1) % numberOfAzimuths; - } else { - if (m_azimuthIndex < desiredAzimuthIndex) - m_azimuthIndex = (m_azimuthIndex + 1) % numberOfAzimuths; - else if (m_azimuthIndex > desiredAzimuthIndex) - m_azimuthIndex = (m_azimuthIndex - 1 + numberOfAzimuths) % numberOfAzimuths; - } - } - - // Get the HRTFKernels and interpolated delays. - HRTFKernel* kernelL; - HRTFKernel* kernelR; - double frameDelayL; - double frameDelayR; - database->getKernelsFromAzimuthElevation(azimuthBlend, m_azimuthIndex, elevation, kernelL, kernelR, frameDelayL, frameDelayR); - - ASSERT(kernelL && kernelR); - if (!kernelL || !kernelR) { - outputBus->zero(); - return; - } - - ASSERT(frameDelayL / sampleRate() < MaxDelayTimeSeconds && frameDelayR / sampleRate() < MaxDelayTimeSeconds); - - // Calculate the source and destination pointers for the current segment. - unsigned offset = segment * framesPerSegment; - float* segmentSourceL = sourceL + offset; - float* segmentSourceR = sourceR + offset; - float* segmentDestinationL = destinationL + offset; - float* segmentDestinationR = destinationR + offset; - - // First run through delay lines for inter-aural time difference. - m_delayLineL.setDelayFrames(frameDelayL); - m_delayLineR.setDelayFrames(frameDelayR); - m_delayLineL.process(segmentSourceL, segmentDestinationL, framesPerSegment); - m_delayLineR.process(segmentSourceR, segmentDestinationR, framesPerSegment); - - // Now do the convolutions in-place. - m_convolverL.process(kernelL->fftFrame(), segmentDestinationL, segmentDestinationL, framesPerSegment); - m_convolverR.process(kernelR->fftFrame(), segmentDestinationR, segmentDestinationR, framesPerSegment); - } -} - -} // namespace WebCore - -#endif // ENABLE(WEB_AUDIO) |