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[ffmpeg] / libavcodec / vp56dsp.c
1 /*
2  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
3  * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
4  *
5  * This file is part of Libav.
6  *
7  * Libav is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * Libav is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21
22 #include <stdint.h>
23
24 #include "libavutil/attributes.h"
25 #include "avcodec.h"
26 #include "vp56dsp.h"
27 #include "libavutil/common.h"
28
29 /* Gives very similar result than the vp6 version except in a few cases */
30 static int vp5_adjust(int v, int t)
31 {
32     int s2, s1 = v >> 31;
33     v ^= s1;
34     v -= s1;
35     v *= v < 2*t;
36     v -= t;
37     s2 = v >> 31;
38     v ^= s2;
39     v -= s2;
40     v = t - v;
41     v += s1;
42     v ^= s1;
43     return v;
44 }
45
46 static int vp6_adjust(int v, int t)
47 {
48     int V = v, s = v >> 31;
49     V ^= s;
50     V -= s;
51     if (V-t-1 >= (unsigned)(t-1))
52         return v;
53     V = 2*t - V;
54     V += s;
55     V ^= s;
56     return V;
57 }
58
59
60 #define VP56_EDGE_FILTER(pfx, suf, pix_inc, line_inc)                   \
61 static void pfx##_edge_filter_##suf(uint8_t *yuv, int stride, int t)    \
62 {                                                                       \
63     int pix2_inc = 2 * pix_inc;                                         \
64     int i, v;                                                           \
65                                                                         \
66     for (i=0; i<12; i++) {                                              \
67         v = (yuv[-pix2_inc] + 3*(yuv[0]-yuv[-pix_inc]) - yuv[pix_inc] + 4)>>3;\
68         v = pfx##_adjust(v, t);                                         \
69         yuv[-pix_inc] = av_clip_uint8(yuv[-pix_inc] + v);               \
70         yuv[0] = av_clip_uint8(yuv[0] - v);                             \
71         yuv += line_inc;                                                \
72     }                                                                   \
73 }
74
75 VP56_EDGE_FILTER(vp5, hor, 1, stride)
76 VP56_EDGE_FILTER(vp5, ver, stride, 1)
77 VP56_EDGE_FILTER(vp6, hor, 1, stride)
78 VP56_EDGE_FILTER(vp6, ver, stride, 1)
79
80 av_cold void ff_vp56dsp_init(VP56DSPContext *s, enum AVCodecID codec)
81 {
82     if (codec == AV_CODEC_ID_VP5) {
83         s->edge_filter_hor = vp5_edge_filter_hor;
84         s->edge_filter_ver = vp5_edge_filter_ver;
85     } else {
86         s->edge_filter_hor = vp6_edge_filter_hor;
87         s->edge_filter_ver = vp6_edge_filter_ver;
88
89         if (CONFIG_VP6_DECODER) {
90             s->vp6_filter_diag4 = ff_vp6_filter_diag4_c;
91
92             if (ARCH_ARM)
93                 ff_vp6dsp_init_arm(s, codec);
94             if (ARCH_X86)
95                 ff_vp6dsp_init_x86(s, codec);
96         }
97     }
98 }