/* * (I)DCT Transforms * Copyright (c) 2009 Peter Ross * Copyright (c) 2010 Alex Converse * Copyright (c) 2010 Vitor Sessak * * 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 St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVCODEC_DCT_H #define AVCODEC_DCT_H #include "rdft.h" struct DCTContext { int nbits; int inverse; RDFTContext rdft; const float *costab; FFTSample *csc2; void (*dct_calc)(struct DCTContext *s, FFTSample *data); void (*dct32)(FFTSample *out, const FFTSample *in); }; /** * Set up DCT. * @param nbits size of the input array: * (1 << nbits) for DCT-II, DCT-III and DST-I * (1 << nbits) + 1 for DCT-I * * @note the first element of the input of DST-I is ignored */ int ff_dct_init(DCTContext *s, int nbits, enum DCTTransformType type); void ff_dct_end (DCTContext *s); #endif