gecko-dev/dom/media/webaudio/FFTBlock.h

320 строки
8.3 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef FFTBlock_h_
#define FFTBlock_h_
#ifdef BUILD_ARM_NEON
#include <cmath>
#include "mozilla/arm.h"
#include "dl/sp/api/omxSP.h"
#endif
#include "AlignedTArray.h"
#include "AudioNodeEngine.h"
#if defined(MOZ_LIBAV_FFT)
#ifdef __cplusplus
extern "C" {
#endif
#include "libavcodec/avfft.h"
#ifdef __cplusplus
}
#endif
#else
#include "kiss_fft/kiss_fftr.h"
#endif
namespace mozilla {
// This class defines an FFT block, loosely modeled after Blink's FFTFrame
// class to make sharing code with Blink easy.
// Currently it's implemented on top of KissFFT on all platforms.
class FFTBlock final
{
union ComplexU {
#if !defined(MOZ_LIBAV_FFT)
kiss_fft_cpx c;
#endif
float f[2];
struct {
float r;
float i;
};
};
public:
explicit FFTBlock(uint32_t aFFTSize)
#if defined(MOZ_LIBAV_FFT)
: mAvRDFT(nullptr)
, mAvIRDFT(nullptr)
#else
: mKissFFT(nullptr)
, mKissIFFT(nullptr)
#ifdef BUILD_ARM_NEON
, mOmxFFT(nullptr)
, mOmxIFFT(nullptr)
#endif
#endif
{
MOZ_COUNT_CTOR(FFTBlock);
SetFFTSize(aFFTSize);
}
~FFTBlock()
{
MOZ_COUNT_DTOR(FFTBlock);
Clear();
}
// Return a new FFTBlock with frequency components interpolated between
// |block0| and |block1| with |interp| between 0.0 and 1.0.
static FFTBlock*
CreateInterpolatedBlock(const FFTBlock& block0,
const FFTBlock& block1, double interp);
// Transform FFTSize() points of aData and store the result internally.
void PerformFFT(const float* aData)
{
EnsureFFT();
#if defined(MOZ_LIBAV_FFT)
PodCopy(mOutputBuffer.Elements()->f, aData, mFFTSize);
av_rdft_calc(mAvRDFT, mOutputBuffer.Elements()->f);
// Recover packed Nyquist.
mOutputBuffer[mFFTSize / 2].r = mOutputBuffer[0].i;
mOutputBuffer[0].i = 0.0f;
#else
#ifdef BUILD_ARM_NEON
if (mozilla::supports_neon()) {
omxSP_FFTFwd_RToCCS_F32_Sfs(aData, mOutputBuffer.Elements()->f, mOmxFFT);
} else
#endif
{
kiss_fftr(mKissFFT, aData, &(mOutputBuffer.Elements()->c));
}
#endif
}
// Inverse-transform internal data and store the resulting FFTSize()
// points in aDataOut.
void GetInverse(float* aDataOut)
{
GetInverseWithoutScaling(aDataOut);
AudioBufferInPlaceScale(aDataOut, 1.0f / mFFTSize, mFFTSize);
}
// Inverse-transform internal frequency data and store the resulting
// FFTSize() points in |aDataOut|. If frequency data has not already been
// scaled, then the output will need scaling by 1/FFTSize().
void GetInverseWithoutScaling(float* aDataOut)
{
EnsureIFFT();
#if defined(MOZ_LIBAV_FFT)
{
// Even though this function doesn't scale, the libav forward transform
// gives a value that needs scaling by 2 in order for things to turn out
// similar to how we expect from kissfft/openmax.
AudioBufferCopyWithScale(mOutputBuffer.Elements()->f, 2.0f,
aDataOut, mFFTSize);
aDataOut[1] = 2.0f * mOutputBuffer[mFFTSize/2].r; // Packed Nyquist
av_rdft_calc(mAvIRDFT, aDataOut);
}
#else
#ifdef BUILD_ARM_NEON
if (mozilla::supports_neon()) {
omxSP_FFTInv_CCSToR_F32_Sfs_unscaled(mOutputBuffer.Elements()->f, aDataOut, mOmxIFFT);
} else
#endif
{
kiss_fftri(mKissIFFT, &(mOutputBuffer.Elements()->c), aDataOut);
}
#endif
}
void Multiply(const FFTBlock& aFrame)
{
uint32_t halfSize = mFFTSize / 2;
// DFTs are not packed.
MOZ_ASSERT(mOutputBuffer[0].i == 0);
MOZ_ASSERT(aFrame.mOutputBuffer[0].i == 0);
BufferComplexMultiply(mOutputBuffer.Elements()->f,
aFrame.mOutputBuffer.Elements()->f,
mOutputBuffer.Elements()->f,
halfSize);
mOutputBuffer[halfSize].r *= aFrame.mOutputBuffer[halfSize].r;
// This would have been set to NaN if either real component was NaN.
mOutputBuffer[0].i = 0.0f;
}
// Perform a forward FFT on |aData|, assuming zeros after dataSize samples,
// and pre-scale the generated internal frequency domain coefficients so
// that GetInverseWithoutScaling() can be used to transform to the time
// domain. This is useful for convolution kernels.
void PadAndMakeScaledDFT(const float* aData, size_t dataSize)
{
MOZ_ASSERT(dataSize <= FFTSize());
AlignedTArray<float> paddedData;
paddedData.SetLength(FFTSize());
AudioBufferCopyWithScale(aData, 1.0f / FFTSize(),
paddedData.Elements(), dataSize);
PodZero(paddedData.Elements() + dataSize, mFFTSize - dataSize);
PerformFFT(paddedData.Elements());
}
void SetFFTSize(uint32_t aSize)
{
mFFTSize = aSize;
mOutputBuffer.SetLength(aSize / 2 + 1);
PodZero(mOutputBuffer.Elements(), aSize / 2 + 1);
Clear();
}
// Return the average group delay and removes this from the frequency data.
double ExtractAverageGroupDelay();
uint32_t FFTSize() const
{
return mFFTSize;
}
float RealData(uint32_t aIndex) const
{
return mOutputBuffer[aIndex].r;
}
float& RealData(uint32_t aIndex)
{
return mOutputBuffer[aIndex].r;
}
float ImagData(uint32_t aIndex) const
{
return mOutputBuffer[aIndex].i;
}
float& ImagData(uint32_t aIndex)
{
return mOutputBuffer[aIndex].i;
}
size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
{
size_t amount = 0;
#if defined(MOZ_LIBAV_FFT)
amount += aMallocSizeOf(mAvRDFT);
amount += aMallocSizeOf(mAvIRDFT);
#else
amount += aMallocSizeOf(mKissFFT);
amount += aMallocSizeOf(mKissIFFT);
#endif
amount += mOutputBuffer.ShallowSizeOfExcludingThis(aMallocSizeOf);
return amount;
}
size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
{
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
private:
FFTBlock(const FFTBlock& other) = delete;
void operator=(const FFTBlock& other) = delete;
void EnsureFFT()
{
#if defined(MOZ_LIBAV_FFT)
if (!mAvRDFT) {
mAvRDFT = av_rdft_init(log((double)mFFTSize)/M_LN2, DFT_R2C);
}
#else
#ifdef BUILD_ARM_NEON
if (mozilla::supports_neon()) {
if (!mOmxFFT) {
mOmxFFT = createOmxFFT(mFFTSize);
}
} else
#endif
{
if (!mKissFFT) {
mKissFFT = kiss_fftr_alloc(mFFTSize, 0, nullptr, nullptr);
}
}
#endif
}
void EnsureIFFT()
{
#if defined(MOZ_LIBAV_FFT)
if (!mAvIRDFT) {
mAvIRDFT = av_rdft_init(log((double)mFFTSize)/M_LN2, IDFT_C2R);
}
#else
#ifdef BUILD_ARM_NEON
if (mozilla::supports_neon()) {
if (!mOmxIFFT) {
mOmxIFFT = createOmxFFT(mFFTSize);
}
} else
#endif
{
if (!mKissIFFT) {
mKissIFFT = kiss_fftr_alloc(mFFTSize, 1, nullptr, nullptr);
}
}
#endif
}
#ifdef BUILD_ARM_NEON
static OMXFFTSpec_R_F32* createOmxFFT(uint32_t aFFTSize)
{
MOZ_ASSERT((aFFTSize & (aFFTSize-1)) == 0);
OMX_INT bufSize;
OMX_INT order = log((double)aFFTSize)/M_LN2;
MOZ_ASSERT(aFFTSize>>order == 1);
OMXResult status = omxSP_FFTGetBufSize_R_F32(order, &bufSize);
if (status == OMX_Sts_NoErr) {
OMXFFTSpec_R_F32* context = static_cast<OMXFFTSpec_R_F32*>(malloc(bufSize));
if (omxSP_FFTInit_R_F32(context, order) != OMX_Sts_NoErr) {
return nullptr;
}
return context;
}
return nullptr;
}
#endif
void Clear()
{
#if defined(MOZ_LIBAV_FFT)
av_rdft_end(mAvRDFT);
av_rdft_end(mAvIRDFT);
mAvRDFT = mAvIRDFT = nullptr;
#else
#ifdef BUILD_ARM_NEON
free(mOmxFFT);
free(mOmxIFFT);
mOmxFFT = mOmxIFFT = nullptr;
#endif
free(mKissFFT);
free(mKissIFFT);
mKissFFT = mKissIFFT = nullptr;
#endif
}
void AddConstantGroupDelay(double sampleFrameDelay);
void InterpolateFrequencyComponents(const FFTBlock& block0,
const FFTBlock& block1, double interp);
#if defined(MOZ_LIBAV_FFT)
RDFTContext *mAvRDFT;
RDFTContext *mAvIRDFT;
#else
kiss_fftr_cfg mKissFFT;
kiss_fftr_cfg mKissIFFT;
#ifdef BUILD_ARM_NEON
OMXFFTSpec_R_F32* mOmxFFT;
OMXFFTSpec_R_F32* mOmxIFFT;
#endif
#endif
AlignedTArray<ComplexU> mOutputBuffer;
uint32_t mFFTSize;
};
} // namespace mozilla
#endif