1 /* 2 * Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com> 3 * 4 * This file is part of FFmpeg. 5 * 6 * FFmpeg is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * FFmpeg is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with FFmpeg; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #ifndef AVCODEC_MDCT15_H 22 #define AVCODEC_MDCT15_H 23 24 #include <stddef.h> 25 26 #include "libavutil/mem_internal.h" 27 28 #include "fft.h" 29 30 typedef struct MDCT15Context { 31 int fft_n; 32 int len2; 33 int len4; 34 int inverse; 35 int *pfa_prereindex; 36 int *pfa_postreindex; 37 38 FFTContext ptwo_fft; 39 FFTComplex *tmp; 40 FFTComplex *twiddle_exptab; 41 42 DECLARE_ALIGNED(32, FFTComplex, exptab)[64]; 43 44 /* 15-point FFT */ 45 void (*fft15)(FFTComplex *out, FFTComplex *in, FFTComplex *exptab, ptrdiff_t stride); 46 47 /* PFA postrotate and exptab */ 48 void (*postreindex)(FFTComplex *out, FFTComplex *in, FFTComplex *exp, int *lut, ptrdiff_t len8); 49 50 /* Calculate a full 2N -> N MDCT */ 51 void (*mdct)(struct MDCT15Context *s, float *dst, const float *src, ptrdiff_t stride); 52 53 /* Calculate the middle half of the iMDCT */ 54 void (*imdct_half)(struct MDCT15Context *s, float *dst, const float *src, 55 ptrdiff_t stride); 56 } MDCT15Context; 57 58 /* Init an (i)MDCT of the length 2 * 15 * (2^N) */ 59 int ff_mdct15_init(MDCT15Context **ps, int inverse, int N, double scale); 60 void ff_mdct15_uninit(MDCT15Context **ps); 61 62 void ff_mdct15_init_x86(MDCT15Context *s); 63 64 #endif /* AVCODEC_MDCT15_H */ 65