14b43beb7c
TBR=niklas.enbom@webrtc.org Review URL: https://webrtc-codereview.appspot.com/915006 git-svn-id: http://webrtc.googlecode.com/svn/trunk@2963 4adac7df-926f-26a2-2b94-8c16560cd09d
73 lines
2.4 KiB
C
73 lines
2.4 KiB
C
/*
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* Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "common_audio/signal_processing/include/real_fft.h"
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#include <stdlib.h>
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#include "common_audio/signal_processing/include/signal_processing_library.h"
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struct RealFFT {
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int order;
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};
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struct RealFFT* WebRtcSpl_CreateRealFFT(int order) {
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struct RealFFT* self = NULL;
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// This constraint comes from ComplexFFT().
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if (order > 10 || order < 0) {
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return NULL;
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}
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self = malloc(sizeof(struct RealFFT));
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self->order = order;
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return self;
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}
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void WebRtcSpl_FreeRealFFT(struct RealFFT* self) {
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free(self);
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}
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// WebRtcSpl_ComplexFFT and WebRtcSpl_ComplexIFFT use in-place algorithm,
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// so copy data from data_in to data_out in the next two functions.
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int WebRtcSpl_RealForwardFFTC(struct RealFFT* self,
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const int16_t* data_in,
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int16_t* data_out) {
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memcpy(data_out, data_in, sizeof(int16_t) * (1 << (self->order + 1)));
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WebRtcSpl_ComplexBitReverse(data_out, self->order);
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return WebRtcSpl_ComplexFFT(data_out, self->order, 1);
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}
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int WebRtcSpl_RealInverseFFTC(struct RealFFT* self,
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const int16_t* data_in,
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int16_t* data_out) {
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memcpy(data_out, data_in, sizeof(int16_t) * (1 << (self->order + 1)));
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WebRtcSpl_ComplexBitReverse(data_out, self->order);
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return WebRtcSpl_ComplexIFFT(data_out, self->order, 1);
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}
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#if defined(WEBRTC_DETECT_ARM_NEON) || defined(WEBRTC_ARCH_ARM_NEON)
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// TODO(kma): Replace the following function bodies into optimized functions
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// for ARM Neon.
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int WebRtcSpl_RealForwardFFTNeon(struct RealFFT* self,
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const int16_t* data_in,
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int16_t* data_out) {
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return WebRtcSpl_RealForwardFFTC(self, data_in, data_out);
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}
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int WebRtcSpl_RealInverseFFTNeon(struct RealFFT* self,
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const int16_t* data_in,
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int16_t* data_out) {
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return WebRtcSpl_RealInverseFFTC(self, data_in, data_out);
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}
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#endif
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