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78 lines
2.2 KiB
78 lines
2.2 KiB
/* |
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* H.264/MPEG-4 Part 10 (Base profile) encoder. |
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* |
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* DSP functions |
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* |
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* Copyright (c) 2006 Expertisecentrum Digitale Media, UHasselt |
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* |
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* FFmpeg is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* FFmpeg is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with FFmpeg; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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/** |
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* @file libavcodec/h264dspenc.c |
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* H.264 encoder related DSP utils |
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* |
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*/ |
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#include "dsputil.h" |
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#define H264_DCT_PART1(X) \ |
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a = block[0][X]+block[3][X]; \ |
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c = block[0][X]-block[3][X]; \ |
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b = block[1][X]+block[2][X]; \ |
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d = block[1][X]-block[2][X]; \ |
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pieces[0][X] = a+b; \ |
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pieces[2][X] = a-b; \ |
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pieces[1][X] = (c<<1)+d; \ |
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pieces[3][X] = c-(d<<1); |
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#define H264_DCT_PART2(X) \ |
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a = pieces[X][0]+pieces[X][3]; \ |
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c = pieces[X][0]-pieces[X][3]; \ |
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b = pieces[X][1]+pieces[X][2]; \ |
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d = pieces[X][1]-pieces[X][2]; \ |
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block[0][X] = a+b; \ |
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block[2][X] = a-b; \ |
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block[1][X] = (c<<1)+d; \ |
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block[3][X] = c-(d<<1); |
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/** |
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* Transform the provided matrix using the H.264 modified DCT. |
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* @note |
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* we'll always work with transposed input blocks, to avoid having to make a |
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* distinction between C and mmx implementations. |
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* |
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* @param block transposed input block |
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*/ |
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static void h264_dct_c(DCTELEM block[4][4]) |
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{ |
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DCTELEM pieces[4][4]; |
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DCTELEM a, b, c, d; |
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H264_DCT_PART1(0); |
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H264_DCT_PART1(1); |
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H264_DCT_PART1(2); |
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H264_DCT_PART1(3); |
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H264_DCT_PART2(0); |
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H264_DCT_PART2(1); |
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H264_DCT_PART2(2); |
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H264_DCT_PART2(3); |
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} |
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void ff_h264dspenc_init(DSPContext* c, AVCodecContext *avctx) |
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{ |
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c->h264_dct = h264_dct_c; |
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} |
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