FFmpeg4/libavcodec/rdft.h

53 lines
1.5 KiB
C

/*
* (I)RDFT transforms
* Copyright (c) 2009 Alex Converse <alex dot converse at gmail dot com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#if !defined(AVCODEC_RDFT_H) && (!defined(FFT_FLOAT) || FFT_FLOAT)
#define AVCODEC_RDFT_H
#include "config.h"
#include "fft.h"
struct RDFTContext {
int nbits;
int inverse;
int sign_convention;
/* pre/post rotation tables */
const FFTSample *tcos;
const FFTSample *tsin;
int negative_sin;
FFTContext fft;
void (*rdft_calc)(struct RDFTContext *s, FFTSample *z);
};
/**
* Set up a real FFT.
* @param nbits log2 of the length of the input array
* @param trans the type of transform
*/
int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans);
void ff_rdft_end(RDFTContext *s);
void ff_rdft_init_arm(RDFTContext *s);
#endif /* AVCODEC_RDFT_H */