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aec3_fft.cc (6496B)


      1 /*
      2 *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
      3 *
      4 *  Use of this source code is governed by a BSD-style license
      5 *  that can be found in the LICENSE file in the root of the source
      6 *  tree. An additional intellectual property rights grant can be found
      7 *  in the file PATENTS.  All contributing project authors may
      8 *  be found in the AUTHORS file in the root of the source tree.
      9 */
     10 
     11 #include "modules/audio_processing/aec3/aec3_fft.h"
     12 
     13 #include <algorithm>
     14 #include <array>
     15 #include <functional>
     16 #include <iterator>
     17 
     18 #include "api/array_view.h"
     19 #include "modules/audio_processing/aec3/aec3_common.h"
     20 #include "modules/audio_processing/aec3/fft_data.h"
     21 #include "rtc_base/checks.h"
     22 #include "rtc_base/cpu_info.h"
     23 
     24 namespace webrtc {
     25 
     26 namespace {
     27 
     28 const float kHanning64[kFftLengthBy2] = {
     29    0.f,         0.00248461f, 0.00991376f, 0.0222136f,  0.03926189f,
     30    0.06088921f, 0.08688061f, 0.11697778f, 0.15088159f, 0.1882551f,
     31    0.22872687f, 0.27189467f, 0.31732949f, 0.36457977f, 0.41317591f,
     32    0.46263495f, 0.51246535f, 0.56217185f, 0.61126047f, 0.65924333f,
     33    0.70564355f, 0.75f,       0.79187184f, 0.83084292f, 0.86652594f,
     34    0.89856625f, 0.92664544f, 0.95048443f, 0.96984631f, 0.98453864f,
     35    0.99441541f, 0.99937846f, 0.99937846f, 0.99441541f, 0.98453864f,
     36    0.96984631f, 0.95048443f, 0.92664544f, 0.89856625f, 0.86652594f,
     37    0.83084292f, 0.79187184f, 0.75f,       0.70564355f, 0.65924333f,
     38    0.61126047f, 0.56217185f, 0.51246535f, 0.46263495f, 0.41317591f,
     39    0.36457977f, 0.31732949f, 0.27189467f, 0.22872687f, 0.1882551f,
     40    0.15088159f, 0.11697778f, 0.08688061f, 0.06088921f, 0.03926189f,
     41    0.0222136f,  0.00991376f, 0.00248461f, 0.f};
     42 
     43 // Hanning window from Matlab command win = sqrt(hanning(128)).
     44 const float kSqrtHanning128[kFftLength] = {
     45    0.00000000000000f, 0.02454122852291f, 0.04906767432742f, 0.07356456359967f,
     46    0.09801714032956f, 0.12241067519922f, 0.14673047445536f, 0.17096188876030f,
     47    0.19509032201613f, 0.21910124015687f, 0.24298017990326f, 0.26671275747490f,
     48    0.29028467725446f, 0.31368174039889f, 0.33688985339222f, 0.35989503653499f,
     49    0.38268343236509f, 0.40524131400499f, 0.42755509343028f, 0.44961132965461f,
     50    0.47139673682600f, 0.49289819222978f, 0.51410274419322f, 0.53499761988710f,
     51    0.55557023301960f, 0.57580819141785f, 0.59569930449243f, 0.61523159058063f,
     52    0.63439328416365f, 0.65317284295378f, 0.67155895484702f, 0.68954054473707f,
     53    0.70710678118655f, 0.72424708295147f, 0.74095112535496f, 0.75720884650648f,
     54    0.77301045336274f, 0.78834642762661f, 0.80320753148064f, 0.81758481315158f,
     55    0.83146961230255f, 0.84485356524971f, 0.85772861000027f, 0.87008699110871f,
     56    0.88192126434835f, 0.89322430119552f, 0.90398929312344f, 0.91420975570353f,
     57    0.92387953251129f, 0.93299279883474f, 0.94154406518302f, 0.94952818059304f,
     58    0.95694033573221f, 0.96377606579544f, 0.97003125319454f, 0.97570213003853f,
     59    0.98078528040323f, 0.98527764238894f, 0.98917650996478f, 0.99247953459871f,
     60    0.99518472667220f, 0.99729045667869f, 0.99879545620517f, 0.99969881869620f,
     61    1.00000000000000f, 0.99969881869620f, 0.99879545620517f, 0.99729045667869f,
     62    0.99518472667220f, 0.99247953459871f, 0.98917650996478f, 0.98527764238894f,
     63    0.98078528040323f, 0.97570213003853f, 0.97003125319454f, 0.96377606579544f,
     64    0.95694033573221f, 0.94952818059304f, 0.94154406518302f, 0.93299279883474f,
     65    0.92387953251129f, 0.91420975570353f, 0.90398929312344f, 0.89322430119552f,
     66    0.88192126434835f, 0.87008699110871f, 0.85772861000027f, 0.84485356524971f,
     67    0.83146961230255f, 0.81758481315158f, 0.80320753148064f, 0.78834642762661f,
     68    0.77301045336274f, 0.75720884650648f, 0.74095112535496f, 0.72424708295147f,
     69    0.70710678118655f, 0.68954054473707f, 0.67155895484702f, 0.65317284295378f,
     70    0.63439328416365f, 0.61523159058063f, 0.59569930449243f, 0.57580819141785f,
     71    0.55557023301960f, 0.53499761988710f, 0.51410274419322f, 0.49289819222978f,
     72    0.47139673682600f, 0.44961132965461f, 0.42755509343028f, 0.40524131400499f,
     73    0.38268343236509f, 0.35989503653499f, 0.33688985339222f, 0.31368174039889f,
     74    0.29028467725446f, 0.26671275747490f, 0.24298017990326f, 0.21910124015687f,
     75    0.19509032201613f, 0.17096188876030f, 0.14673047445536f, 0.12241067519922f,
     76    0.09801714032956f, 0.07356456359967f, 0.04906767432742f, 0.02454122852291f};
     77 
     78 bool IsSse2Available() {
     79 #if defined(WEBRTC_ARCH_X86_FAMILY)
     80  return cpu_info::Supports(cpu_info::ISA::kSSE2);
     81 #else
     82  return false;
     83 #endif
     84 }
     85 
     86 }  // namespace
     87 
     88 Aec3Fft::Aec3Fft() : ooura_fft_(IsSse2Available()) {}
     89 
     90 // TODO(peah): Change x to be std::array once the rest of the code allows this.
     91 void Aec3Fft::ZeroPaddedFft(ArrayView<const float> x,
     92                            Window window,
     93                            FftData* X) const {
     94  RTC_DCHECK(X);
     95  RTC_DCHECK_EQ(kFftLengthBy2, x.size());
     96  std::array<float, kFftLength> fft;
     97  std::fill(fft.begin(), fft.begin() + kFftLengthBy2, 0.f);
     98  switch (window) {
     99    case Window::kRectangular:
    100      std::copy(x.begin(), x.end(), fft.begin() + kFftLengthBy2);
    101      break;
    102    case Window::kHanning:
    103      std::transform(x.begin(), x.end(), std::begin(kHanning64),
    104                     fft.begin() + kFftLengthBy2,
    105                     [](float a, float b) { return a * b; });
    106      break;
    107    case Window::kSqrtHanning:
    108      RTC_DCHECK_NOTREACHED();
    109      break;
    110    default:
    111      RTC_DCHECK_NOTREACHED();
    112  }
    113 
    114  Fft(&fft, X);
    115 }
    116 
    117 void Aec3Fft::PaddedFft(ArrayView<const float> x,
    118                        ArrayView<const float> x_old,
    119                        Window window,
    120                        FftData* X) const {
    121  RTC_DCHECK(X);
    122  RTC_DCHECK_EQ(kFftLengthBy2, x.size());
    123  RTC_DCHECK_EQ(kFftLengthBy2, x_old.size());
    124  std::array<float, kFftLength> fft;
    125 
    126  switch (window) {
    127    case Window::kRectangular:
    128      std::copy(x_old.begin(), x_old.end(), fft.begin());
    129      std::copy(x.begin(), x.end(), fft.begin() + x_old.size());
    130      break;
    131    case Window::kHanning:
    132      RTC_DCHECK_NOTREACHED();
    133      break;
    134    case Window::kSqrtHanning:
    135      std::transform(x_old.begin(), x_old.end(), std::begin(kSqrtHanning128),
    136                     fft.begin(), std::multiplies<float>());
    137      std::transform(x.begin(), x.end(),
    138                     std::begin(kSqrtHanning128) + x_old.size(),
    139                     fft.begin() + x_old.size(), std::multiplies<float>());
    140      break;
    141    default:
    142      RTC_DCHECK_NOTREACHED();
    143  }
    144 
    145  Fft(&fft, X);
    146 }
    147 
    148 }  // namespace webrtc