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/*
* Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.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
*/
#ifndef AVCODEC_MDCT15_H
#define AVCODEC_MDCT15_H
#include <stddef.h>
#include "fft.h"
typedef struct MDCT15Context {
int fft_n;
int len2;
int len4;
int inverse;
int *pfa_prereindex;
int *pfa_postreindex;
FFTContext ptwo_fft;
FFTComplex *tmp;
FFTComplex *twiddle_exptab;
/* 0 - 18: fft15 twiddles, 19 - 20: fft5 twiddles */
FFTComplex exptab[21];
/**
* Calculate a full 2N -> N MDCT
*/
void (*mdct)(struct MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride);
/**
* Calculate the middle half of the iMDCT
*/
void (*imdct_half)(struct MDCT15Context *s, float *dst, const float *src,
ptrdiff_t src_stride, float scale);
} MDCT15Context;
/**
* Init an (i)MDCT of the length 2 * 15 * (2^N)
*/
int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale);
/**
* Frees a context
*/
void ff_mdct15_uninit(MDCT15Context **ps);
#endif /* AVCODEC_MDCT15_H */
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