1 files changed, 348 insertions, 0 deletions
diff --git a/dom/media/webaudio/FFTBlock.h b/dom/media/webaudio/FFTBlock.h
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+++ b/dom/media/webaudio/FFTBlock.h
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+/* -*- 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)
+#  include "FFmpegRDFTTypes.h"
+#  include "FFVPXRuntimeLinker.h"
+#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:
+  static void MainThreadInit() {
+#ifdef MOZ_LIBAV_FFT
+    FFVPXRuntimeLinker::Init();
+    if (!sRDFTFuncs.init) {
+      FFVPXRuntimeLinker::GetRDFTFuncs(&sRDFTFuncs);
+    }
+#endif
+  }
+
+  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) {
+    if (!EnsureFFT()) {
+      return;
+    }
+
+#if defined(MOZ_LIBAV_FFT)
+    PodCopy(mOutputBuffer.Elements()->f, aData, mFFTSize);
+    sRDFTFuncs.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) {
+    if (!EnsureIFFT()) {
+      std::fill_n(aDataOut, mFFTSize, 0.0f);
+      return;
+    };
+
+#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
+      sRDFTFuncs.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());
+  }
+
+  // aSize must be a power of 2
+  void SetFFTSize(uint32_t aSize) {
+    MOZ_ASSERT(CountPopulation32(aSize) == 1);
+    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)
+    auto ComputedSizeOfContextIfSet = [this](void* aContext) -> size_t {
+      if (!aContext) {
+        return 0;
+      }
+      // RDFTContext is only forward declared in public headers, but this is
+      // an estimate based on a value of 231 seen requested from
+      // _aligned_alloc on Win64.  Don't use malloc_usable_size() because the
+      // context pointer is not necessarily from malloc.
+      size_t amount = 232;
+      // Add size of allocations performed in ff_fft_init().
+      // The maximum FFT size used is 32768 = 2^15 and so revtab32 is not
+      // allocated.
+      MOZ_ASSERT(mFFTSize <= 32768);
+      amount += mFFTSize * (sizeof(uint16_t) + 2 * sizeof(float));
+
+      return amount;
+    };
+
+    amount += ComputedSizeOfContextIfSet(mAvRDFT);
+    amount += ComputedSizeOfContextIfSet(mAvIRDFT);
+#else
+#  ifdef BUILD_ARM_NEON
+    amount += aMallocSizeOf(mOmxFFT);
+    amount += aMallocSizeOf(mOmxIFFT);
+#  endif
+#  ifdef USE_SIMD
+#    error kiss fft uses malloc only when USE_SIMD is not defined
+#  endif
+    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;
+
+  bool EnsureFFT() {
+#if defined(MOZ_LIBAV_FFT)
+    if (!mAvRDFT) {
+      if (!sRDFTFuncs.init) {
+        return false;
+      }
+
+      mAvRDFT = sRDFTFuncs.init(FloorLog2(mFFTSize), 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
+    return true;
+  }
+
+  bool EnsureIFFT() {
+#if defined(MOZ_LIBAV_FFT)
+    if (!mAvIRDFT) {
+      if (!sRDFTFuncs.init) {
+        return false;
+      }
+
+      mAvIRDFT = sRDFTFuncs.init(FloorLog2(mFFTSize), 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
+    return true;
+  }
+
+#ifdef BUILD_ARM_NEON
+  static OMXFFTSpec_R_F32* createOmxFFT(uint32_t aFFTSize) {
+    MOZ_ASSERT((aFFTSize & (aFFTSize - 1)) == 0);
+    OMX_INT bufSize;
+    OMX_INT order = FloorLog2(aFFTSize);
+    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)
+    if (mAvRDFT) {
+      sRDFTFuncs.end(mAvRDFT);
+      mAvRDFT = nullptr;
+    }
+    if (mAvIRDFT) {
+      sRDFTFuncs.end(mAvIRDFT);
+      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)
+  static FFmpegRDFTFuncs sRDFTFuncs;
+  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