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 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
  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     }
  93
  94     if (ARCH_ARM) ff_vp56dsp_init_arm(s, codec);
  95     if (ARCH_X86) ff_vp56dsp_init_x86(s, codec);
  96 }