From c6b237da9e77c969833514567a54f4cc44ca874a Mon Sep 17 00:00:00 2001 From: Panagiotis Issaris Date: Mon, 11 Dec 2006 15:53:55 +0000 Subject: Adding H.264 DCT. Originally committed as revision 7282 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/h264dsp.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 libavcodec/h264dsp.c (limited to 'libavcodec/h264dsp.c') diff --git a/libavcodec/h264dsp.c b/libavcodec/h264dsp.c new file mode 100644 index 0000000000..4f18afac4a --- /dev/null +++ b/libavcodec/h264dsp.c @@ -0,0 +1,81 @@ +/* + * H.264/MPEG-4 Part 10 (Base profile) encoder. + * + * DSP functions + * + * Copyright (c) 2006 Expertisecentrum Digitale Media, UHasselt + * + * 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 + */ + +/** + * @file h264dsp.c + * H.264 encoder related DSP utils + * + */ + +#include "dsputil.h" + +extern const uint8_t ff_div6[52]; +extern const uint8_t ff_rem6[52]; + +#define H264_DCT_PART1(X) \ + a = block[0][X]+block[3][X]; \ + c = block[0][X]-block[3][X]; \ + b = block[1][X]+block[2][X]; \ + d = block[1][X]-block[2][X]; \ + pieces[0][X] = a+b; \ + pieces[2][X] = a-b; \ + pieces[1][X] = (c<<1)+d; \ + pieces[3][X] = c-(d<<1); + +#define H264_DCT_PART2(X) \ + a = pieces[X][0]+pieces[X][3]; \ + c = pieces[X][0]-pieces[X][3]; \ + b = pieces[X][1]+pieces[X][2]; \ + d = pieces[X][1]-pieces[X][2]; \ + block[0][X] = a+b; \ + block[2][X] = a-b; \ + block[1][X] = (c<<1)+d; \ + block[3][X] = c-(d<<1); + +/** + * Transform the provided matrix using the H.264 modified DCT. + * @note + * we'll always work with transposed input blocks, to avoid having to make a + * distinction between C and mmx implementations. + * + * @param block transposed input block + */ +static void h264_dct_c(DCTELEM block[4][4]) +{ + DCTELEM pieces[4][4]; + DCTELEM a, b, c, d; + + H264_DCT_PART1(0); + H264_DCT_PART1(1); + H264_DCT_PART1(2); + H264_DCT_PART1(3); + H264_DCT_PART2(0); + H264_DCT_PART2(1); + H264_DCT_PART2(2); + H264_DCT_PART2(3); +} + +void ff_h264dsp_init(DSPContext* c, AVCodecContext *avctx) +{ + c->h264_dct = h264_dct_c; +} + -- cgit v1.2.3