workbench/classes/datatypes/mpegvideo/mpegordered.c

   1
   2 /*
   3 **
   4 **  $VER: mpegordered.c 1.8 (3.5.97)
   5 **  mpegvideo.datatype 1.8
   6 **
   7 **  This file contains C code to implement an
   8 **  ordered dither.
   9 **
  10 **  Written 1996/1997 by Roland 'Gizzy' Mainz
  11 **
  12 */
  13
  14 /* project includes */
  15 #include "mpegvideo.h"
  16 #include "mpegproto.h"
  17
  18
  19 /*
  20  *--------------------------------------------------------------
  21  *
  22  *  InitOrderedDither--
  23  *
  24  *    Structures intialized for ordered dithering.
  25  *
  26  * Results:
  27  *    None.
  28  *
  29  * Side effects:
  30  *    None.
  31  *
  32  *--------------------------------------------------------------
  33  */
  34
  35
  36 void InitOrderedDither( struct MPEGVideoInstData *mvid )
  37 {
  38   long   i,
  39          j,
  40          k,
  41          err_range,
  42          threshval;
  43   ULONG *lmark,
  44         *cmark;
  45
  46   for( i = 0 ; i < DITH_SIZE ; i++ )
  47   {
  48     lmark = l_darrays[ i ] = (ULONG *)mymalloc( mvid, (256 * sizeof( ULONG )) );
  49
  50     for( j = 0 ; j < lum_values[ 0 ] ; j++)
  51     {
  52       *lmark++ = 0;
  53     }
  54
  55     for( j = 0 ; j < (LUM_RANGE - 1) ; j++ )
  56     {
  57       err_range = lum_values[ j + 1 ] - lum_values[ j ];
  58       threshval = ((i * err_range) / DITH_SIZE) + lum_values[ j ];
  59
  60       for( k = lum_values[ j ] ; k < lum_values[ j + 1 ] ; k++ )
  61       {
  62         if( k > threshval )
  63           *lmark++ = ((j + 1) * (CR_RANGE * CB_RANGE));
  64         else
  65           *lmark++ = (j * (CR_RANGE * CB_RANGE));
  66       }
  67     }
  68
  69     for( j = lum_values[ LUM_RANGE - 1 ] ; j < 256 ; j++ )
  70     {
  71       *lmark++ = (LUM_RANGE - 1) * (CR_RANGE * CB_RANGE);
  72     }
  73   }
  74
  75   for( i = 0 ; i < DITH_SIZE ; i++ )
  76   {
  77     cmark = cr_darrays[ i ] = (ULONG *)mymalloc( mvid, (256 * sizeof( ULONG )) );
  78
  79     for( j = 0 ; j < cr_values[ 0 ] ; j++ )
  80     {
  81       *cmark++ = 0;
  82     }
  83
  84     for( j = 0 ; j < (CR_RANGE - 1) ; j++ )
  85     {
  86       err_range = cr_values[ j + 1 ] - cr_values[ j ];
  87       threshval = ((i * err_range) / DITH_SIZE) + cr_values[ j ];
  88
  89       for( k = cr_values[ j ] ; k < cr_values[ j + 1 ] ; k++ )
  90       {
  91         if( k > threshval )
  92           *cmark++ = ((j + 1) * CB_RANGE);
  93         else
  94           *cmark++ = (j * CB_RANGE);
  95       }
  96     }
  97
  98     for( j = cr_values[ CR_RANGE - 1 ] ; j < 256 ; j++ )
  99     {
 100       *cmark++ = (CR_RANGE - 1) * (CB_RANGE);
 101     }
 102   }
 103
 104   for( i = 0 ; i < DITH_SIZE ; i++ )
 105   {
 106     cmark = cb_darrays[ i ] = (ULONG *)mymalloc( mvid, (256 * sizeof( ULONG )) );
 107
 108     for( j = 0 ; j < cb_values[ 0 ] ; j++ )
 109     {
 110       *cmark++ = 0;
 111     }
 112
 113     for( j = 0 ; j < (CB_RANGE - 1) ; j++ )
 114     {
 115       err_range = cb_values[ j + 1 ] - cb_values[ j ];
 116       threshval = ((i * err_range) / DITH_SIZE) + cb_values[ j ];
 117
 118       for( k = cb_values[ j ] ; k < cb_values[ j + 1 ] ; k++ )
 119       {
 120         if( k > threshval )
 121           *cmark++ = j+1;
 122         else
 123           *cmark++ = j;
 124       }
 125     }
 126
 127     for( j = cb_values[ CB_RANGE - 1 ] ; j < 256 ; j++ )
 128     {
 129       *cmark++ = CB_RANGE - 1;
 130     }
 131   }
 132 }
 133
 134
 135 /*
 136  *--------------------------------------------------------------
 137  *
 138  * OrderedDitherImage --
 139  *
 140  *  Dithers an image using an ordered dither.
 141  *  Assumptions made:
 142  *    1) The color space is allocated y:cr:cb = 8:4:4
 143  *    2) The spatial resolution of y:cr:cb is 4:1:1
 144  *      The channels are dithered based on the standard
 145  *      ordered dither pattern for a 4x4 area.
 146  *
 147  * Results:
 148  *   None.
 149  *
 150  * Side effects:
 151  *   None.
 152  *
 153  *--------------------------------------------------------------
 154  */
 155
 156
 157 void OrderedDitherImage( struct MPEGVideoInstData *mvid, UBYTE *lum, UBYTE *cr, UBYTE *cb, UBYTE *out, UWORD h, UWORD w )
 158 {
 159     UBYTE *l, *r, *b, *o1, *o2;
 160     UBYTE *l2;
 161     UBYTE  L, R, B;
 162     UWORD  i,
 163            j;
 164
 165     l     = lum;
 166     l2    = lum + w;
 167     r     = cr;
 168     b     = cb;
 169     o1    = out;
 170     o2    = out + w;
 171
 172     for( i = 0U ; i < h ; i += 4U )
 173     {
 174       for( j = 0U ; j < w ; j += 8U )
 175       {
 176         R = r[ 0 ]; B = b[ 0 ];
 177
 178         L = l[  0 ]; o1[ 0 ] = mappixel[ (l_darrays[  0 ][ L ]   + cr_darrays[  0 ][ R ]  + cb_darrays[  0 ][ B ]) ];
 179         L = l[  1 ]; o1[ 1 ] = mappixel[ (l_darrays[  8 ][ L ]   + cr_darrays[  8 ][ R ]  + cb_darrays[  8 ][ B ]) ];
 180         L = l2[ 0 ]; o2[ 0 ] = mappixel[ (l_darrays[ 12 ][ L ]   + cr_darrays[ 12 ][ R ]  + cb_darrays[ 12 ][ B ]) ];
 181         L = l2[ 1 ]; o2[ 1 ] = mappixel[ (l_darrays[  4 ][ L ]   + cr_darrays[  4 ][ R ]  + cb_darrays[  4 ][ B ]) ];
 182
 183         R = r[ 1 ]; B = b[ 1 ];
 184
 185         L = l[  2 ]; o1[ 2 ] = mappixel[ (l_darrays[  2 ][ L ]  + cr_darrays[  2 ][ R ] + cb_darrays[  2 ][ B ]) ];
 186         L = l[  3 ]; o1[ 3 ] = mappixel[ (l_darrays[ 10 ][ L ]  + cr_darrays[ 10 ][ R ] + cb_darrays[ 10 ][ B ]) ];
 187         L = l2[ 2 ]; o2[ 2 ] = mappixel[ (l_darrays[ 14 ][ L ]  + cr_darrays[ 14 ][ R ] + cb_darrays[ 14 ][ B ]) ];
 188         L = l2[ 3 ]; o2[ 3 ] = mappixel[ (l_darrays[  6 ][ L ]  + cr_darrays[  6 ][ R ] + cb_darrays[  6 ][ B ]) ];
 189
 190         R = r[ 2 ]; B = b[ 2 ];
 191
 192         L = l[  4 ]; o1[ 4 ] = mappixel[ (l_darrays[  0 ][ L ]  + cr_darrays[  0 ][ R ] + cb_darrays[  0 ][ B ]) ];
 193         L = l[  5 ]; o1[ 5 ] = mappixel[ (l_darrays[  8 ][ L ]  + cr_darrays[  8 ][ R ] + cb_darrays[  8 ][ B ]) ];
 194         L = l2[ 4 ]; o2[ 4 ] = mappixel[ (l_darrays[ 12 ][ L ]  + cr_darrays[ 12 ][ R ] + cb_darrays[ 12 ][ B ]) ];
 195         L = l2[ 5 ]; o2[ 5 ] = mappixel[ (l_darrays[  4 ][ L ]  + cr_darrays[  4 ][ R ] + cb_darrays[  4 ][ B ]) ];
 196
 197         R = r[ 3 ]; B = b[ 3 ];
 198
 199         L = l[  6 ]; o1[ 6 ] = mappixel[ (l_darrays[  2 ][ L ]  + cr_darrays[  2 ][ R ] + cb_darrays[  2 ][ B ]) ];
 200         L = l[  7 ]; o1[ 7 ] = mappixel[ (l_darrays[ 10 ][ L ]  + cr_darrays[ 10 ][ R ] + cb_darrays[ 10 ][ B ]) ];
 201         L = l2[ 6 ]; o2[ 6 ] = mappixel[ (l_darrays[ 14 ][ L ]  + cr_darrays[ 14 ][ R ] + cb_darrays[ 14 ][ B ]) ];
 202         L = l2[ 7 ]; o2[ 7 ] = mappixel[ (l_darrays[  6 ][ L ]  + cr_darrays[  6 ][ R ] + cb_darrays[  6 ][ B ]) ];
 203
 204         l  += 8;
 205         l2 += 8;
 206         r  += 4;
 207         b  += 4;
 208         o1 += 8;
 209         o2 += 8;
 210       }
 211
 212       l  += w; l2 += w;
 213       o1 += w; o2 += w;
 214
 215       for( j = 0 ; j < w ; j += 8 )
 216       {
 217         R = r[ 0 ]; B = b[ 0 ];
 218
 219         L = l[  0 ]; o1[ 0 ] = mappixel[ (l_darrays[  3 ][ L ]  + cr_darrays[  3 ][ R ] + cb_darrays[  3 ][ B ]) ];
 220         L = l[  1 ]; o1[ 1 ] = mappixel[ (l_darrays[ 11 ][ L ]  + cr_darrays[ 11 ][ R ] + cb_darrays[ 11 ][ B ]) ];
 221         L = l2[ 0 ]; o2[ 0 ] = mappixel[ (l_darrays[ 15 ][ L ]  + cr_darrays[ 15 ][ R ] + cb_darrays[ 15 ][ B ]) ];
 222         L = l2[ 1 ]; o2[ 1 ] = mappixel[ (l_darrays[  7 ][ L ]  + cr_darrays[  7 ][ R ] + cb_darrays[  7 ][ B ]) ];
 223
 224         R = r[ 1 ]; B = b[ 1 ];
 225
 226         L = l[  2 ]; o1[ 2 ] = mappixel[ (l_darrays[  1 ][ L ]  + cr_darrays[  1 ][ R ] + cb_darrays[  1 ][ B ]) ];
 227         L = l[  3 ]; o1[ 3 ] = mappixel[ (l_darrays[  9 ][ L ]  + cr_darrays[  9 ][ R ] + cb_darrays[  9 ][ B ]) ];
 228         L = l2[ 2 ]; o2[ 2 ] = mappixel[ (l_darrays[ 13 ][ L ]  + cr_darrays[ 13 ][ R ] + cb_darrays[ 13 ][ B ]) ];
 229         L = l2[ 3 ]; o2[ 3 ] = mappixel[ (l_darrays[  5 ][ L ]  + cr_darrays[  5 ][ R ] + cb_darrays[  5 ][ B ]) ];
 230
 231         R = r[ 2 ]; B = b[ 2 ];
 232
 233         L = l[  4 ]; o1[ 4 ] = mappixel[ (l_darrays[  3 ][ L ]  + cr_darrays[  3 ][ R ] + cb_darrays[  3 ][ B ]) ];
 234         L = l[  5 ]; o1[ 5 ] = mappixel[ (l_darrays[ 11 ][ L ]  + cr_darrays[ 11 ][ R ] + cb_darrays[ 11 ][ B ]) ];
 235         L = l2[ 4 ]; o2[ 4 ] = mappixel[ (l_darrays[ 15 ][ L ]  + cr_darrays[ 15 ][ R ] + cb_darrays[ 15 ][ B ]) ];
 236         L = l2[ 5 ]; o2[ 5 ] = mappixel[ (l_darrays[  7 ][ L ]  + cr_darrays[  7 ][ R ] + cb_darrays[  7 ][ B ]) ];
 237
 238         R = r[ 3 ]; B = b[ 3 ];
 239
 240         L = l[  6 ]; o1[ 6 ] = mappixel[ (l_darrays[  1 ][ L ]  + cr_darrays[  1 ][ R ] + cb_darrays[  1 ][ B ]) ];
 241         L = l[  7 ]; o1[ 7 ] = mappixel[ (l_darrays[  9 ][ L ]  + cr_darrays[  9 ][ R ] + cb_darrays[  9 ][ B ]) ];
 242         L = l2[ 6 ]; o2[ 6 ] = mappixel[ (l_darrays[ 13 ][ L ]  + cr_darrays[ 13 ][ R ] + cb_darrays[ 13 ][ B ]) ];
 243         L = l2[ 7 ]; o2[ 7 ] = mappixel[ (l_darrays[  5 ][ L ]  + cr_darrays[  5 ][ R ] + cb_darrays[  5 ][ B ]) ];
 244
 245         l  += 8;
 246         l2 += 8;
 247         r  += 4;
 248         b  += 4;
 249         o1 += 8;
 250         o2 += 8;
 251       }
 252
 253       l  += w; l2 += w;
 254       o1 += w; o2 += w;
 255     }
 256 }
 257
 258
 259