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