/*
  * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
  * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include <stdint.h>
 #include "avcodec.h"
 #include "vp56dsp.h"

 #include "libavutil/common.h"

 
 /* Gives very similar result than the vp6 version except in a few cases */
 static int vp5_adjust(int v, int t)
 {
     int s2, s1 = v >> 31;
     v ^= s1;
     v -= s1;
     v *= v < 2*t;
     v -= t;
     s2 = v >> 31;
     v ^= s2;
     v -= s2;
     v = t - v;
     v += s1;
     v ^= s1;
     return v;
 }
 
 static int vp6_adjust(int v, int t)
 {
     int V = v, s = v >> 31;
     V ^= s;
     V -= s;
     if (V-t-1 >= (unsigned)(t-1))
         return v;
     V = 2*t - V;
     V += s;
     V ^= s;
     return V;
 }
 
 
 #define VP56_EDGE_FILTER(pfx, suf, pix_inc, line_inc)                   \
 static void pfx##_edge_filter_##suf(uint8_t *yuv, int stride, int t)    \
 {                                                                       \
     int pix2_inc = 2 * pix_inc;                                         \
     int i, v;                                                           \
                                                                         \
     for (i=0; i<12; i++) {                                              \
         v = (yuv[-pix2_inc] + 3*(yuv[0]-yuv[-pix_inc]) - yuv[pix_inc] + 4)>>3;\
         v = pfx##_adjust(v, t);                                         \
         yuv[-pix_inc] = av_clip_uint8(yuv[-pix_inc] + v);               \
         yuv[0] = av_clip_uint8(yuv[0] - v);                             \
         yuv += line_inc;                                                \
     }                                                                   \
 }
 
 VP56_EDGE_FILTER(vp5, hor, 1, stride)
 VP56_EDGE_FILTER(vp5, ver, stride, 1)
 VP56_EDGE_FILTER(vp6, hor, 1, stride)
 VP56_EDGE_FILTER(vp6, ver, stride, 1)
 

 void ff_vp56dsp_init(VP56DSPContext *s, enum AVCodecID codec)

 {

     if (codec == AV_CODEC_ID_VP5) {

         s->edge_filter_hor = vp5_edge_filter_hor;
         s->edge_filter_ver = vp5_edge_filter_ver;
     } else {
         s->edge_filter_hor = vp6_edge_filter_hor;
         s->edge_filter_ver = vp6_edge_filter_ver;

 
         if (CONFIG_VP6_DECODER) {

             s->vp6_filter_diag4 = ff_vp6_filter_diag4_c;

         }

     }

 
     if (ARCH_ARM) ff_vp56dsp_init_arm(s, codec);

     if (ARCH_X86) ff_vp56dsp_init_x86(s, codec);

 }