1/* 2 * H.264/MPEG-4 Part 10 (Base profile) encoder. 3 * 4 * DSP functions 5 * 6 * Copyright (c) 2006 Expertisecentrum Digitale Media, UHasselt 7 * 8 * FFmpeg is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU Lesser General Public 10 * License as published by the Free Software Foundation; either 11 * version 2.1 of the License, or (at your option) any later version. 12 * 13 * FFmpeg is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * Lesser General Public License for more details. 17 * 18 * You should have received a copy of the GNU Lesser General Public 19 * License along with FFmpeg; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 21 */ 22 23/** 24 * @file 25 * H.264 encoder related DSP utils 26 * 27 */ 28 29#include "dsputil.h" 30 31#define H264_DCT_PART1(X) \ 32 a = block[0][X]+block[3][X]; \ 33 c = block[0][X]-block[3][X]; \ 34 b = block[1][X]+block[2][X]; \ 35 d = block[1][X]-block[2][X]; \ 36 pieces[0][X] = a+b; \ 37 pieces[2][X] = a-b; \ 38 pieces[1][X] = (c<<1)+d; \ 39 pieces[3][X] = c-(d<<1); 40 41#define H264_DCT_PART2(X) \ 42 a = pieces[X][0]+pieces[X][3]; \ 43 c = pieces[X][0]-pieces[X][3]; \ 44 b = pieces[X][1]+pieces[X][2]; \ 45 d = pieces[X][1]-pieces[X][2]; \ 46 block[0][X] = a+b; \ 47 block[2][X] = a-b; \ 48 block[1][X] = (c<<1)+d; \ 49 block[3][X] = c-(d<<1); 50 51/** 52 * Transform the provided matrix using the H.264 modified DCT. 53 * @note 54 * we'll always work with transposed input blocks, to avoid having to make a 55 * distinction between C and mmx implementations. 56 * 57 * @param block transposed input block 58 */ 59static void h264_dct_c(DCTELEM block[4][4]) 60{ 61 DCTELEM pieces[4][4]; 62 DCTELEM a, b, c, d; 63 64 H264_DCT_PART1(0); 65 H264_DCT_PART1(1); 66 H264_DCT_PART1(2); 67 H264_DCT_PART1(3); 68 H264_DCT_PART2(0); 69 H264_DCT_PART2(1); 70 H264_DCT_PART2(2); 71 H264_DCT_PART2(3); 72} 73 74av_cold void ff_h264dspenc_init(DSPContext* c, AVCodecContext *avctx) 75{ 76 c->h264_dct = h264_dct_c; 77} 78 79