1 /* 2 * (I)RDFT transforms 3 * Copyright (c) 2009 Alex Converse <alex dot converse at gmail dot com> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22 #if !defined(AVCODEC_RDFT_H) && (!defined(FFT_FLOAT) || FFT_FLOAT) 23 #define AVCODEC_RDFT_H 24 25 #include "config.h" 26 #include "fft.h" 27 28 struct RDFTContext { 29 int nbits; 30 int inverse; 31 int sign_convention; 32 33 /* pre/post rotation tables */ 34 const FFTSample *tcos; 35 const FFTSample *tsin; 36 int negative_sin; 37 FFTContext fft; 38 void (*rdft_calc)(struct RDFTContext *s, FFTSample *z); 39 }; 40 41 /** 42 * Set up a real FFT. 43 * @param nbits log2 of the length of the input array 44 * @param trans the type of transform 45 */ 46 int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans); 47 void ff_rdft_end(RDFTContext *s); 48 49 void ff_rdft_init_arm(RDFTContext *s); 50 51 52 #endif /* AVCODEC_RDFT_H */ 53