blob: f8f8b6f17ba4ed52d27b131d99fc5a53038aaaa7 [file] [log] [blame]
* Copyright (c) 2011 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.
* File:
* fftn.h
* ---------------------------------------------------------------------*
* Re[]: real value array
* Im[]: imaginary value array
* nTotal: total number of complex values
* nPass: number of elements involved in this pass of transform
* nSpan: nspan/nPass = number of bytes to increment pointer
* in Re[] and Im[]
* isign: exponent: +1 = forward -1 = reverse
* scaling: normalizing constant by which the final result is *divided*
* scaling == -1, normalize by total dimension of the transform
* scaling < -1, normalize by the square-root of the total dimension
* ----------------------------------------------------------------------
* See the comments in the code for correct usage!
#define FFT_MAXFFTSIZE 2048
#define FFT_NFACTOR 11
typedef struct {
unsigned int SpaceAlloced;
unsigned int MaxPermAlloced;
double Tmp0[FFT_MAXFFTSIZE];
double Tmp1[FFT_MAXFFTSIZE];
double Tmp2[FFT_MAXFFTSIZE];
double Tmp3[FFT_MAXFFTSIZE];
int factor[FFT_NFACTOR];
} FFTstr;
/* double precision routine */
int WebRtcIsac_Fftns(unsigned int ndim,
const int dims[],
double Re[],
double Im[],
int isign,
double scaling,
FFTstr* fftstate);