git.sesse.net Git - vlc/blob - plugins/yuv/video_yuv_macros_8bpp.h

   1 /*****************************************************************************
   2  * video_yuv_macros_8bpp.h: YUV transformation macros for 8bpp
   3  *****************************************************************************
   4  * Copyright (C) 1999, 2000 VideoLAN
   5  *
   6  * Authors:
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public
  19  * License along with this program; if not, write to the
  20  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  21  * Boston, MA 02111-1307, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * CONVERT_4YUV_PIXELS: dither 4 pixels in 8 bpp
  26  *****************************************************************************
  27  * These macros dither 4 pixels in 8 bpp
  28  *****************************************************************************/
  29 #define CONVERT_4YUV_PIXELS( CHROMA )                                         \
  30     *p_pic++ = p_lookup[                                                      \
  31         (((*p_y++ + dither10[i_real_y]) >> 4) << 7)                           \
  32       + ((*p_u + dither20[i_real_y]) >> 5) * 9                                \
  33       + ((*p_v + dither20[i_real_y]) >> 5) ];                                 \
  34     *p_pic++ = p_lookup[                                                      \
  35         (((*p_y++ + dither11[i_real_y]) >> 4) << 7)                           \
  36       + ((*p_u++ + dither21[i_real_y]) >> 5) * 9                              \
  37       + ((*p_v++ + dither21[i_real_y]) >> 5) ];                               \
  38     *p_pic++ = p_lookup[                                                      \
  39         (((*p_y++ + dither12[i_real_y]) >> 4) << 7)                           \
  40       + ((*p_u + dither22[i_real_y]) >> 5) * 9                                \
  41       + ((*p_v + dither22[i_real_y]) >> 5) ];                                 \
  42     *p_pic++ = p_lookup[                                                      \
  43         (((*p_y++ + dither13[i_real_y]) >> 4) << 7)                           \
  44       + ((*p_u++ + dither23[i_real_y]) >> 5) * 9                              \
  45       + ((*p_v++ + dither23[i_real_y]) >> 5) ];                               \
  46
  47 /*****************************************************************************
  48  * CONVERT_4YUV_PIXELS_SCALE: dither and scale 4 pixels in 8 bpp
  49  *****************************************************************************
  50  * These macros dither 4 pixels in 8 bpp, with horizontal scaling
  51  *****************************************************************************/
  52 #define CONVERT_4YUV_PIXELS_SCALE( CHROMA )                                   \
  53     *p_pic++ = p_lookup[                                                      \
  54         ( ((*p_y + dither10[i_real_y]) >> 4) << 7)                            \
  55         + ((*p_u + dither20[i_real_y]) >> 5) * 9                              \
  56         + ((*p_v + dither20[i_real_y]) >> 5) ];                               \
  57     b_jump_uv += *p_offset;                                                   \
  58     p_y += *p_offset;                                                         \
  59     p_u += *p_offset   & b_jump_uv;                                           \
  60     p_v += *p_offset++ & b_jump_uv;                                           \
  61     *p_pic++ = p_lookup[                                                      \
  62         ( ((*p_y + dither11[i_real_y]) >> 4) << 7)                            \
  63         + ((*p_u + dither21[i_real_y]) >> 5) * 9                              \
  64         + ((*p_v + dither21[i_real_y]) >> 5) ];                               \
  65     b_jump_uv += *p_offset;                                                   \
  66     p_y += *p_offset;                                                         \
  67     p_u += *p_offset   & b_jump_uv;                                           \
  68     p_v += *p_offset++ & b_jump_uv;                                           \
  69     *p_pic++ = p_lookup[                                                      \
  70         ( ((*p_y + dither12[i_real_y]) >> 4) << 7)                            \
  71         + ((*p_u + dither22[i_real_y]) >> 5) * 9                              \
  72         + ((*p_v + dither22[i_real_y]) >> 5) ];                               \
  73     b_jump_uv += *p_offset;                                                   \
  74     p_y += *p_offset;                                                         \
  75     p_u += *p_offset   & b_jump_uv;                                           \
  76     p_v += *p_offset++ & b_jump_uv;                                           \
  77     *p_pic++ = p_lookup[                                                      \
  78         ( ((*p_y + dither13[i_real_y]) >> 4) << 7)                            \
  79         + ((*p_u + dither23[i_real_y]) >> 5) * 9                              \
  80         + ((*p_v + dither23[i_real_y]) >> 5) ];                               \
  81     b_jump_uv += *p_offset;                                                   \
  82     p_y += *p_offset;                                                         \
  83     p_u += *p_offset   & b_jump_uv;                                           \
  84     p_v += *p_offset++ & b_jump_uv;                                           \
  85
  86 /*****************************************************************************
  87  * SCALE_WIDTH_DITHER: scale a line horizontally for dithered 8 bpp
  88  *****************************************************************************
  89  * This macro scales a line using an offset array.
  90  *****************************************************************************/
  91 #define SCALE_WIDTH_DITHER( CHROMA )                                          \
  92     if( b_horizontal_scaling )                                                \
  93     {                                                                         \
  94         /* Horizontal scaling, but we can't use a buffer due to dither */     \
  95         p_offset = p_offset_start;                                            \
  96         b_jump_uv = 0;                                                        \
  97         for( i_x = i_pic_width / 16; i_x--; )                                 \
  98         {                                                                     \
  99             CONVERT_4YUV_PIXELS_SCALE( CHROMA )                               \
 100             CONVERT_4YUV_PIXELS_SCALE( CHROMA )                               \
 101             CONVERT_4YUV_PIXELS_SCALE( CHROMA )                               \
 102             CONVERT_4YUV_PIXELS_SCALE( CHROMA )                               \
 103         }                                                                     \
 104     }                                                                         \
 105     else                                                                      \
 106     {                                                                         \
 107         for( i_x = i_width / 16; i_x--;  )                                    \
 108         {                                                                     \
 109             CONVERT_4YUV_PIXELS( CHROMA )                                     \
 110             CONVERT_4YUV_PIXELS( CHROMA )                                     \
 111             CONVERT_4YUV_PIXELS( CHROMA )                                     \
 112             CONVERT_4YUV_PIXELS( CHROMA )                                     \
 113         }                                                                     \
 114     }                                                                         \
 115     /* Increment of picture pointer to end of line is still needed */         \
 116     p_pic += i_pic_line_width;                                                \
 117     i_real_y = (i_real_y + 1) & 0x3;                                          \
 118
 119 /*****************************************************************************
 120  * SCALE_HEIGHT_DITHER: handle vertical scaling for dithered 8 bpp
 121  *****************************************************************************
 122  * This macro handles vertical scaling for a picture. CHROMA may be 420, 422 or
 123  * 444 for RGB conversion, or 400 for gray conversion.
 124  *****************************************************************************/
 125 #define SCALE_HEIGHT_DITHER( CHROMA )                                         \
 126                                                                               \
 127     /* If line is odd, rewind 4:2:0 U and V samples */                        \
 128     if( ((CHROMA == 420) || (CHROMA == 422)) && !(i_y & 0x1) )                \
 129     {                                                                         \
 130         p_u -= i_chroma_width;                                                \
 131         p_v -= i_chroma_width;                                                \
 132     }                                                                         \
 133                                                                               \
 134     /*                                                                        \
 135      * Handle vertical scaling. The current line can be copied or next one    \
 136      * can be ignored.                                                        \
 137      */                                                                       \
 138                                                                               \
 139     switch( i_vertical_scaling )                                              \
 140     {                                                                         \
 141     case -1:                             /* vertical scaling factor is < 1 */ \
 142         while( (i_scale_count -= i_pic_height) >= 0 )                         \
 143         {                                                                     \
 144             /* Height reduction: skip next source line */                     \
 145             p_y += i_width;                                                   \
 146             i_y++;                                                            \
 147             if( (CHROMA == 420) || (CHROMA == 422) )                          \
 148             {                                                                 \
 149                 if( i_y & 0x1 )                                               \
 150                 {                                                             \
 151                     p_u += i_chroma_width;                                    \
 152                     p_v += i_chroma_width;                                    \
 153                 }                                                             \
 154             }                                                                 \
 155             else if( CHROMA == 444 )                                          \
 156             {                                                                 \
 157                 p_u += i_width;                                               \
 158                 p_v += i_width;                                               \
 159             }                                                                 \
 160         }                                                                     \
 161         i_scale_count += i_height;                                            \
 162         break;                                                                \
 163     case 1:                              /* vertical scaling factor is > 1 */ \
 164         while( (i_scale_count -= i_height) > 0 )                              \
 165         {                                                                     \
 166             SCALE_WIDTH_DITHER( CHROMA );                                     \
 167             p_y -= i_width;                                                   \
 168             p_u -= i_chroma_width;                                            \
 169             p_v -= i_chroma_width;                                            \
 170             p_pic +=        i_pic_line_width;                                 \
 171         }                                                                     \
 172         i_scale_count += i_pic_height;                                        \
 173         break;                                                                \
 174     }                                                                         \
 175