1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/webaudio/blink/HRTFKernel.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,118 @@
1.4 +/*
1.5 + * Copyright (C) 2010 Google Inc. All rights reserved.
1.6 + *
1.7 + * Redistribution and use in source and binary forms, with or without
1.8 + * modification, are permitted provided that the following conditions
1.9 + * are met:
1.10 + *
1.11 + * 1. Redistributions of source code must retain the above copyright
1.12 + * notice, this list of conditions and the following disclaimer.
1.13 + * 2. Redistributions in binary form must reproduce the above copyright
1.14 + * notice, this list of conditions and the following disclaimer in the
1.15 + * documentation and/or other materials provided with the distribution.
1.16 + * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
1.17 + * its contributors may be used to endorse or promote products derived
1.18 + * from this software without specific prior written permission.
1.19 + *
1.20 + * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
1.21 + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
1.22 + * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
1.23 + * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
1.24 + * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
1.25 + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
1.26 + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
1.27 + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.28 + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
1.29 + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.30 + */
1.31 +
1.32 +#ifndef HRTFKernel_h
1.33 +#define HRTFKernel_h
1.34 +
1.35 +#include "nsAutoPtr.h"
1.36 +#include "nsAutoRef.h"
1.37 +#include "nsTArray.h"
1.38 +#include "mozilla/FFTBlock.h"
1.39 +#include "mozilla/MemoryReporting.h"
1.40 +
1.41 +namespace WebCore {
1.42 +
1.43 +using mozilla::FFTBlock;
1.44 +
1.45 +// HRTF stands for Head-Related Transfer Function.
1.46 +// HRTFKernel is a frequency-domain representation of an impulse-response used as part of the spatialized panning system.
1.47 +// For a given azimuth / elevation angle there will be one HRTFKernel for the left ear transfer function, and one for the right ear.
1.48 +// The leading delay (average group delay) for each impulse response is extracted:
1.49 +// m_fftFrame is the frequency-domain representation of the impulse response with the delay removed
1.50 +// m_frameDelay is the leading delay of the original impulse response.
1.51 +class HRTFKernel {
1.52 +public:
1.53 + // Note: this is destructive on the passed in |impulseResponse|.
1.54 + // The |length| of |impulseResponse| must be a power of two.
1.55 + // The size of the DFT will be |2 * length|.
1.56 + static nsReturnRef<HRTFKernel> create(float* impulseResponse, size_t length, float sampleRate);
1.57 +
1.58 + static nsReturnRef<HRTFKernel> create(nsAutoPtr<FFTBlock> fftFrame, float frameDelay, float sampleRate);
1.59 +
1.60 + // Given two HRTFKernels, and an interpolation factor x: 0 -> 1, returns an interpolated HRTFKernel.
1.61 + static nsReturnRef<HRTFKernel> createInterpolatedKernel(HRTFKernel* kernel1, HRTFKernel* kernel2, float x);
1.62 +
1.63 + FFTBlock* fftFrame() { return m_fftFrame.get(); }
1.64 +
1.65 + size_t fftSize() const { return m_fftFrame->FFTSize(); }
1.66 + float frameDelay() const { return m_frameDelay; }
1.67 +
1.68 + float sampleRate() const { return m_sampleRate; }
1.69 + double nyquist() const { return 0.5 * sampleRate(); }
1.70 +
1.71 + size_t sizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
1.72 + {
1.73 + size_t amount = aMallocSizeOf(this);
1.74 + amount += m_fftFrame->SizeOfIncludingThis(aMallocSizeOf);
1.75 + return amount;
1.76 + }
1.77 +
1.78 +private:
1.79 + HRTFKernel(const HRTFKernel& other) MOZ_DELETE;
1.80 + void operator=(const HRTFKernel& other) MOZ_DELETE;
1.81 +
1.82 + // Note: this is destructive on the passed in |impulseResponse|.
1.83 + HRTFKernel(float* impulseResponse, size_t fftSize, float sampleRate);
1.84 +
1.85 + HRTFKernel(nsAutoPtr<FFTBlock> fftFrame, float frameDelay, float sampleRate)
1.86 + : m_fftFrame(fftFrame)
1.87 + , m_frameDelay(frameDelay)
1.88 + , m_sampleRate(sampleRate)
1.89 + {
1.90 + }
1.91 +
1.92 + nsAutoPtr<FFTBlock> m_fftFrame;
1.93 + float m_frameDelay;
1.94 + float m_sampleRate;
1.95 +};
1.96 +
1.97 +typedef nsTArray<nsAutoRef<HRTFKernel> > HRTFKernelList;
1.98 +
1.99 +} // namespace WebCore
1.100 +
1.101 +template <>
1.102 +class nsAutoRefTraits<WebCore::HRTFKernel> :
1.103 + public nsPointerRefTraits<WebCore::HRTFKernel> {
1.104 +public:
1.105 + static void Release(WebCore::HRTFKernel* ptr) { delete(ptr); }
1.106 +};
1.107 +
1.108 +namespace WebCore {
1.109 +
1.110 +inline nsReturnRef<HRTFKernel> HRTFKernel::create(float* impulseResponse, size_t length, float sampleRate)
1.111 +{
1.112 + return nsReturnRef<HRTFKernel>(new HRTFKernel(impulseResponse, length, sampleRate));
1.113 +}
1.114 +
1.115 +inline nsReturnRef<HRTFKernel> HRTFKernel::create(nsAutoPtr<FFTBlock> fftFrame, float frameDelay, float sampleRate)
1.116 +{
1.117 + return nsReturnRef<HRTFKernel>(new HRTFKernel(fftFrame, frameDelay, sampleRate));
1.118 +}
1.119 +
1.120 +} // namespace WebCore
1.121 +#endif // HRTFKernel_h
