9eb9299a369387c300b880a498e432147ac35a6f
[libav.git] / 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 FFmpeg.
6 *
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; 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 #include "avcodec.h"
24 #include "vp56dsp.h"
25
26 /* Gives very similar result than the vp6 version except in a few cases */
27 static int vp5_adjust(int v, int t)
28 {
29 int s2, s1 = v >> 31;
30 v ^= s1;
31 v -= s1;
32 v *= v < 2*t;
33 v -= t;
34 s2 = v >> 31;
35 v ^= s2;
36 v -= s2;
37 v = t - v;
38 v += s1;
39 v ^= s1;
40 return v;
41 }
42
43 static int vp6_adjust(int v, int t)
44 {
45 int V = v, s = v >> 31;
46 V ^= s;
47 V -= s;
48 if (V-t-1 >= (unsigned)(t-1))
49 return v;
50 V = 2*t - V;
51 V += s;
52 V ^= s;
53 return V;
54 }
55
56
57 #define VP56_EDGE_FILTER(pfx, suf, pix_inc, line_inc) \
58 static void pfx##_edge_filter_##suf(uint8_t *yuv, int stride, int t) \
59 { \
60 int pix2_inc = 2 * pix_inc; \
61 int i, v; \
62 \
63 for (i=0; i<12; i++) { \
64 v = (yuv[-pix2_inc] + 3*(yuv[0]-yuv[-pix_inc]) - yuv[pix_inc] + 4)>>3;\
65 v = pfx##_adjust(v, t); \
66 yuv[-pix_inc] = av_clip_uint8(yuv[-pix_inc] + v); \
67 yuv[0] = av_clip_uint8(yuv[0] - v); \
68 yuv += line_inc; \
69 } \
70 }
71
72 VP56_EDGE_FILTER(vp5, hor, 1, stride)
73 VP56_EDGE_FILTER(vp5, ver, stride, 1)
74 VP56_EDGE_FILTER(vp6, hor, 1, stride)
75 VP56_EDGE_FILTER(vp6, ver, stride, 1)
76
77 void ff_vp56dsp_init(VP56DSPContext *s, enum CodecID codec)
78 {
79 if (codec == CODEC_ID_VP5) {
80 s->edge_filter_hor = vp5_edge_filter_hor;
81 s->edge_filter_ver = vp5_edge_filter_ver;
82 } else {
83 s->edge_filter_hor = vp6_edge_filter_hor;
84 s->edge_filter_ver = vp6_edge_filter_ver;
85 }
86
87 if (ARCH_ARM) ff_vp56dsp_init_arm(s, codec);
88 }