blob: 47bad4e57ff87e99e8815b8230a27a25ec4da8ca
1 | /* |
2 | * H.261 common code |
3 | * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at> |
4 | * Copyright (c) 2004 Maarten Daniels |
5 | * |
6 | * This file is part of FFmpeg. |
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.261 codec |
26 | */ |
27 | |
28 | #include "avcodec.h" |
29 | #include "h261.h" |
30 | |
31 | #define IS_FIL(a) ((a) & MB_TYPE_H261_FIL) |
32 | |
33 | uint8_t ff_h261_rl_table_store[2][2 * MAX_RUN + MAX_LEVEL + 3]; |
34 | |
35 | static void h261_loop_filter(uint8_t *src, int stride) |
36 | { |
37 | int x, y, xy, yz; |
38 | int temp[64]; |
39 | |
40 | for (x = 0; x < 8; x++) { |
41 | temp[x] = 4 * src[x]; |
42 | temp[x + 7 * 8] = 4 * src[x + 7 * stride]; |
43 | } |
44 | for (y = 1; y < 7; y++) { |
45 | for (x = 0; x < 8; x++) { |
46 | xy = y * stride + x; |
47 | yz = y * 8 + x; |
48 | temp[yz] = src[xy - stride] + 2 * src[xy] + src[xy + stride]; |
49 | } |
50 | } |
51 | |
52 | for (y = 0; y < 8; y++) { |
53 | src[y * stride] = (temp[y * 8] + 2) >> 2; |
54 | src[y * stride + 7] = (temp[y * 8 + 7] + 2) >> 2; |
55 | for (x = 1; x < 7; x++) { |
56 | xy = y * stride + x; |
57 | yz = y * 8 + x; |
58 | src[xy] = (temp[yz - 1] + 2 * temp[yz] + temp[yz + 1] + 8) >> 4; |
59 | } |
60 | } |
61 | } |
62 | |
63 | void ff_h261_loop_filter(MpegEncContext *s) |
64 | { |
65 | H261Context *h = (H261Context *)s; |
66 | const int linesize = s->linesize; |
67 | const int uvlinesize = s->uvlinesize; |
68 | uint8_t *dest_y = s->dest[0]; |
69 | uint8_t *dest_cb = s->dest[1]; |
70 | uint8_t *dest_cr = s->dest[2]; |
71 | |
72 | if (!(IS_FIL(h->mtype))) |
73 | return; |
74 | |
75 | h261_loop_filter(dest_y, linesize); |
76 | h261_loop_filter(dest_y + 8, linesize); |
77 | h261_loop_filter(dest_y + 8 * linesize, linesize); |
78 | h261_loop_filter(dest_y + 8 * linesize + 8, linesize); |
79 | h261_loop_filter(dest_cb, uvlinesize); |
80 | h261_loop_filter(dest_cr, uvlinesize); |
81 | } |
82 | |
83 | av_cold void ff_h261_common_init(void) |
84 | { |
85 | static int done = 0; |
86 | |
87 | if (done) |
88 | return; |
89 | |
90 | ff_rl_init(&ff_h261_rl_tcoeff, ff_h261_rl_table_store); |
91 | done = 1; |
92 | } |
93 |