76 lines
2.4 KiB
C
76 lines
2.4 KiB
C
|
/*
|
||
|
|
* Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
|
||
|
|
*
|
||
|
|
* Use of this source code is governed by a BSD-style license
|
||
|
|
* that can be found in the LICENSE file in the root of the source
|
||
|
|
* tree. An additional intellectual property rights grant can be found
|
||
|
|
* in the file PATENTS. All contributing project authors may
|
||
|
|
* be found in the AUTHORS file in the root of the source tree.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef MODULES_AUDIO_PROCESSING_AEC3_AEC3_FFT_H_
|
||
|
|
#define MODULES_AUDIO_PROCESSING_AEC3_AEC3_FFT_H_
|
||
|
|
|
||
|
|
#include <array>
|
||
|
|
|
||
|
|
#include "api/array_view.h"
|
||
|
|
#include "common_audio/third_party/ooura/fft_size_128/ooura_fft.h"
|
||
|
|
#include "modules/audio_processing/aec3/aec3_common.h"
|
||
|
|
#include "modules/audio_processing/aec3/fft_data.h"
|
||
|
|
#include "rtc_base/checks.h"
|
||
|
|
|
||
|
|
namespace webrtc {
|
||
|
|
|
||
|
|
// Wrapper class that provides 128 point real valued FFT functionality with the
|
||
|
|
// FftData type.
|
||
|
|
class Aec3Fft {
|
||
|
|
public:
|
||
|
|
enum class Window { kRectangular, kHanning, kSqrtHanning };
|
||
|
|
|
||
|
|
Aec3Fft();
|
||
|
|
|
||
|
|
Aec3Fft(const Aec3Fft&) = delete;
|
||
|
|
Aec3Fft& operator=(const Aec3Fft&) = delete;
|
||
|
|
|
||
|
|
// Computes the FFT. Note that both the input and output are modified.
|
||
|
|
void Fft(std::array<float, kFftLength>* x, FftData* X) const {
|
||
|
|
RTC_DCHECK(x);
|
||
|
|
RTC_DCHECK(X);
|
||
|
|
ooura_fft_.Fft(x->data());
|
||
|
|
X->CopyFromPackedArray(*x);
|
||
|
|
}
|
||
|
|
// Computes the inverse Fft.
|
||
|
|
void Ifft(const FftData& X, std::array<float, kFftLength>* x) const {
|
||
|
|
RTC_DCHECK(x);
|
||
|
|
X.CopyToPackedArray(x);
|
||
|
|
ooura_fft_.InverseFft(x->data());
|
||
|
|
}
|
||
|
|
|
||
|
|
// Windows the input using a Hanning window, and then adds padding of
|
||
|
|
// kFftLengthBy2 initial zeros before computing the Fft.
|
||
|
|
void ZeroPaddedFft(rtc::ArrayView<const float> x,
|
||
|
|
Window window,
|
||
|
|
FftData* X) const;
|
||
|
|
|
||
|
|
// Concatenates the kFftLengthBy2 values long x and x_old before computing the
|
||
|
|
// Fft. After that, x is copied to x_old.
|
||
|
|
void PaddedFft(rtc::ArrayView<const float> x,
|
||
|
|
rtc::ArrayView<const float> x_old,
|
||
|
|
FftData* X) const {
|
||
|
|
PaddedFft(x, x_old, Window::kRectangular, X);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Padded Fft using a time-domain window.
|
||
|
|
void PaddedFft(rtc::ArrayView<const float> x,
|
||
|
|
rtc::ArrayView<const float> x_old,
|
||
|
|
Window window,
|
||
|
|
FftData* X) const;
|
||
|
|
|
||
|
|
private:
|
||
|
|
const OouraFft ooura_fft_;
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace webrtc
|
||
|
|
|
||
|
|
#endif // MODULES_AUDIO_PROCESSING_AEC3_AEC3_FFT_H_
|