git.sesse.net Git - vlc/blob - modules/codec/mpeg_video/motion/motion.c

   1 /*****************************************************************************
   2  * motion.c : C motion compensation module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2001 VideoLAN
   5  * $Id: motion.c,v 1.2 2002/08/08 00:35:11 sam Exp $
   6  *
   7  * Authors: Aaron Holtzman <aholtzma@ess.engr.uvic.ca>
   8  *          Michel Lespinasse <walken@zoy.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  27  *****************************************************************************/
  28 #include <stdlib.h>                                      /* malloc(), free() */
  29 #include <string.h>
  30
  31 #include <vlc/vlc.h>
  32
  33 /*****************************************************************************
  34  * Local prototype
  35  *****************************************************************************/
  36 static int Open ( vlc_object_t * );
  37
  38 /*****************************************************************************
  39  * Module descriptor
  40  *****************************************************************************/
  41 vlc_module_begin();
  42     set_description( _("motion compensation module") );
  43     set_capability( "motion compensation", 50 );
  44     add_shortcut( "c" );
  45     set_callbacks( Open, NULL );
  46 vlc_module_end();
  47
  48 /*****************************************************************************
  49  * Simple motion compensation in C
  50  *****************************************************************************/
  51
  52 #define avg2(a,b) ((a+b+1)>>1)
  53 #define avg4(a,b,c,d) ((a+b+c+d+2)>>2)
  54
  55 #define predict_o(i) (ref[i])
  56 #define predict_x(i) (avg2 (ref[i], ref[i+1]))
  57 #define predict_y(i) (avg2 (ref[i], (ref+stride)[i]))
  58 #define predict_xy(i) (avg4 (ref[i], ref[i+1], (ref+stride)[i], (ref+stride)[i+1]))
  59
  60 #define put(predictor,i) dest[i] = predictor (i)
  61 #define avg(predictor,i) dest[i] = avg2 (predictor (i), dest[i])
  62
  63 /* mc function template */
  64
  65 #define MC_FUNC(op,xy)                                                      \
  66 static void MC_##op##_##xy##16_c (yuv_data_t * dest, yuv_data_t * ref,      \
  67                                  int stride, int height)                    \
  68 {                                                                           \
  69     do {                                                                    \
  70         op (predict_##xy, 0);                                               \
  71         op (predict_##xy, 1);                                               \
  72         op (predict_##xy, 2);                                               \
  73         op (predict_##xy, 3);                                               \
  74         op (predict_##xy, 4);                                               \
  75         op (predict_##xy, 5);                                               \
  76         op (predict_##xy, 6);                                               \
  77         op (predict_##xy, 7);                                               \
  78         op (predict_##xy, 8);                                               \
  79         op (predict_##xy, 9);                                               \
  80         op (predict_##xy, 10);                                              \
  81         op (predict_##xy, 11);                                              \
  82         op (predict_##xy, 12);                                              \
  83         op (predict_##xy, 13);                                              \
  84         op (predict_##xy, 14);                                              \
  85         op (predict_##xy, 15);                                              \
  86         ref += stride;                                                      \
  87         dest += stride;                                                     \
  88     } while (--height);                                                     \
  89 }                                                                           \
  90 static void MC_##op##_##xy##8_c (yuv_data_t * dest, yuv_data_t * ref,       \
  91                                 int stride, int height)                     \
  92 {                                                                           \
  93     do {                                                                    \
  94         op (predict_##xy, 0);                                               \
  95         op (predict_##xy, 1);                                               \
  96         op (predict_##xy, 2);                                               \
  97         op (predict_##xy, 3);                                               \
  98         op (predict_##xy, 4);                                               \
  99         op (predict_##xy, 5);                                               \
 100         op (predict_##xy, 6);                                               \
 101         op (predict_##xy, 7);                                               \
 102         ref += stride;                                                      \
 103         dest += stride;                                                     \
 104     } while (--height);                                                     \
 105 }
 106
 107 /* definitions of the actual mc functions */
 108
 109 MC_FUNC (put,o)
 110 MC_FUNC (avg,o)
 111 MC_FUNC (put,x)
 112 MC_FUNC (avg,x)
 113 MC_FUNC (put,y)
 114 MC_FUNC (avg,y)
 115 MC_FUNC (put,xy)
 116 MC_FUNC (avg,xy)
 117
 118 /*****************************************************************************
 119  * Functions exported as capabilities. They are declared as static so that
 120  * we don't pollute the namespace too much.
 121  *****************************************************************************/
 122 static void (* ppppf_motion[2][2][4])( yuv_data_t *, yuv_data_t *, int, int ) =
 123 {
 124     /* Copying functions */
 125     {
 126         /* Width == 16 */
 127         { MC_put_o16_c, MC_put_x16_c, MC_put_y16_c, MC_put_xy16_c },
 128         /* Width == 8 */
 129         { MC_put_o8_c,  MC_put_x8_c,  MC_put_y8_c, MC_put_xy8_c }
 130     },
 131     /* Averaging functions */
 132     {
 133         /* Width == 16 */
 134         { MC_avg_o16_c, MC_avg_x16_c, MC_avg_y16_c, MC_avg_xy16_c },
 135         /* Width == 8 */
 136         { MC_avg_o8_c,  MC_avg_x8_c,  MC_avg_y8_c,  MC_avg_xy8_c }
 137     }
 138 };
 139
 140 static int Open ( vlc_object_t *p_this )
 141 {
 142     p_this->p_private = ppppf_motion;
 143     return VLC_SUCCESS;
 144 }
 145