git.sesse.net Git - ffmpeg/blob - 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 #include "avcodec.h"
  24 #include "vp56dsp.h"
  25 #include "libavutil/common.h"
  26
  27 /* Gives very similar result than the vp6 version except in a few cases */
  28 static int vp5_adjust(int v, int t)
  29 {
  30     int s2, s1 = v >> 31;
  31     v ^= s1;
  32     v -= s1;
  33     v *= v < 2*t;
  34     v -= t;
  35     s2 = v >> 31;
  36     v ^= s2;
  37     v -= s2;
  38     v = t - v;
  39     v += s1;
  40     v ^= s1;
  41     return v;
  42 }
  43
  44 static int vp6_adjust(int v, int t)
  45 {
  46     int V = v, s = v >> 31;
  47     V ^= s;
  48     V -= s;
  49     if (V-t-1 >= (unsigned)(t-1))
  50         return v;
  51     V = 2*t - V;
  52     V += s;
  53     V ^= s;
  54     return V;
  55 }
  56
  57
  58 #define VP56_EDGE_FILTER(pfx, suf, pix_inc, line_inc)                   \
  59 static void pfx##_edge_filter_##suf(uint8_t *yuv, int stride, int t)    \
  60 {                                                                       \
  61     int pix2_inc = 2 * pix_inc;                                         \
  62     int i, v;                                                           \
  63                                                                         \
  64     for (i=0; i<12; i++) {                                              \
  65         v = (yuv[-pix2_inc] + 3*(yuv[0]-yuv[-pix_inc]) - yuv[pix_inc] + 4)>>3;\
  66         v = pfx##_adjust(v, t);                                         \
  67         yuv[-pix_inc] = av_clip_uint8(yuv[-pix_inc] + v);               \
  68         yuv[0] = av_clip_uint8(yuv[0] - v);                             \
  69         yuv += line_inc;                                                \
  70     }                                                                   \
  71 }
  72
  73 VP56_EDGE_FILTER(vp5, hor, 1, stride)
  74 VP56_EDGE_FILTER(vp5, ver, stride, 1)
  75 VP56_EDGE_FILTER(vp6, hor, 1, stride)
  76 VP56_EDGE_FILTER(vp6, ver, stride, 1)
  77
  78 void ff_vp56dsp_init(VP56DSPContext *s, enum AVCodecID codec)
  79 {
  80     if (codec == AV_CODEC_ID_VP5) {
  81         s->edge_filter_hor = vp5_edge_filter_hor;
  82         s->edge_filter_ver = vp5_edge_filter_ver;
  83     } else {
  84         s->edge_filter_hor = vp6_edge_filter_hor;
  85         s->edge_filter_ver = vp6_edge_filter_ver;
  86
  87         if (CONFIG_VP6_DECODER) {
  88             s->vp6_filter_diag4 = ff_vp6_filter_diag4_c;
  89         }
  90     }
  91
  92     if (ARCH_ARM) ff_vp56dsp_init_arm(s, codec);
  93     if (ARCH_X86) ff_vp56dsp_init_x86(s, codec);
  94 }