tests/utils.c

   1 /*
   2  * This file is part of Libav.
   3  *
   4  * Libav is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * Libav is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with Libav; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #include <errno.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 #define SCALEBITS 8
  25 #define ONE_HALF  (1 << (SCALEBITS - 1))
  26 #define FIX(x)    ((int) ((x) * (1L << SCALEBITS) + 0.5))
  27
  28 #define err_if(expr) do {                                              \
  29     if (expr) {                                                        \
  30         fprintf(stderr, "%s\n", strerror(errno));                      \
  31         exit(1);                                                       \
  32     }                                                                  \
  33 } while (0)
  34
  35 static void rgb24_to_yuv420p(unsigned char *lum, unsigned char *cb,
  36                              unsigned char *cr, unsigned char *src,
  37                              int width, int height)
  38 {
  39     int wrap, wrap3, x, y;
  40     int r, g, b, r1, g1, b1;
  41     unsigned char *p;
  42
  43     wrap  = width;
  44     wrap3 = width * 3;
  45     p     = src;
  46     for (y = 0; y < height; y += 2) {
  47         for (x = 0; x < width; x += 2) {
  48             r       = p[0];
  49             g       = p[1];
  50             b       = p[2];
  51             r1      = r;
  52             g1      = g;
  53             b1      = b;
  54             lum[0]  = (FIX(0.29900) * r + FIX(0.58700) * g +
  55                        FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
  56             r       = p[3];
  57             g       = p[4];
  58             b       = p[5];
  59             r1     += r;
  60             g1     += g;
  61             b1     += b;
  62             lum[1]  = (FIX(0.29900) * r + FIX(0.58700) * g +
  63                        FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
  64             p      += wrap3;
  65             lum    += wrap;
  66
  67             r       = p[0];
  68             g       = p[1];
  69             b       = p[2];
  70             r1     += r;
  71             g1     += g;
  72             b1     += b;
  73             lum[0]  = (FIX(0.29900) * r + FIX(0.58700) * g +
  74                        FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
  75             r       = p[3];
  76             g       = p[4];
  77             b       = p[5];
  78             r1     += r;
  79             g1     += g;
  80             b1     += b;
  81             lum[1]  = (FIX(0.29900) * r + FIX(0.58700) * g +
  82                        FIX(0.11400) * b + ONE_HALF) >> SCALEBITS;
  83
  84             cb[0]   = ((- FIX(0.16874) * r1 - FIX(0.33126) * g1 +
  85                        FIX(0.50000) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
  86             cr[0]   = ((FIX(0.50000) * r1 - FIX(0.41869) * g1 -
  87                        FIX(0.08131) * b1 + 4 * ONE_HALF - 1) >> (SCALEBITS + 2)) + 128;
  88
  89             cb++;
  90             cr++;
  91             p   += -wrap3 + 2 * 3;
  92             lum += -wrap  + 2;
  93         }
  94         p   += wrap3;
  95         lum += wrap;
  96     }
  97 }
  98
  99 /* cif format */
 100 #define DEFAULT_WIDTH   352
 101 #define DEFAULT_HEIGHT  288
 102 #define DEFAULT_NB_PICT  50
 103
 104 static void pgmyuv_save(const char *filename, int w, int h,
 105                         unsigned char *rgb_tab)
 106 {
 107     FILE *f;
 108     int i, h2, w2;
 109     unsigned char *cb, *cr;
 110     unsigned char *lum_tab, *cb_tab, *cr_tab;
 111
 112     lum_tab = malloc(w * h);
 113     cb_tab  = malloc(w * h / 4);
 114     cr_tab  = malloc(w * h / 4);
 115
 116     rgb24_to_yuv420p(lum_tab, cb_tab, cr_tab, rgb_tab, w, h);
 117
 118     if (filename) {
 119         f = fopen(filename, "wb");
 120         fprintf(f, "P5\n%d %d\n%d\n", w, h * 3 / 2, 255);
 121     } else {
 122         f = stdout;
 123     }
 124
 125     err_if(fwrite(lum_tab, 1, w * h, f) != w * h);
 126     h2 = h / 2;
 127     w2 = w / 2;
 128     cb = cb_tab;
 129     cr = cr_tab;
 130
 131     if (filename) {
 132         for (i = 0; i < h2; i++) {
 133             err_if(fwrite(cb, 1, w2, f) != w2);
 134             err_if(fwrite(cr, 1, w2, f) != w2);
 135             cb += w2;
 136             cr += w2;
 137         }
 138         fclose(f);
 139     } else {
 140         for (i = 0; i < h2; i++) {
 141             err_if(fwrite(cb, 1, w2, f) != w2);
 142             cb += w2;
 143         }
 144         for (i = 0; i < h2; i++) {
 145             err_if(fwrite(cr, 1, w2, f) != w2);
 146             cr += w2;
 147         }
 148     }
 149
 150     free(lum_tab);
 151     free(cb_tab);
 152     free(cr_tab);
 153 }
 154
 155 static unsigned char *rgb_tab;
 156 static int width, height, wrap;
 157
 158 static void put_pixel(int x, int y, int r, int g, int b)
 159 {
 160     unsigned char *p;
 161
 162     if (x < 0 || x >= width ||
 163         y < 0 || y >= height)
 164         return;
 165
 166     p    = rgb_tab + y * wrap + x * 3;
 167     p[0] = r;
 168     p[1] = g;
 169     p[2] = b;
 170 }