tests/rgb_to_ycbcr.c

   1 /* babl - dynamically extendable universal pixel conversion library.
   2  * Copyright (C) 2005, Øyvind Kolås.
   3  *
   4  * This library 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 3 of the License, or (at your option) any later version.
   8  *
   9  * This library 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
  15  * Public License along with this library; if not, see
  16  * <https://www.gnu.org/licenses/>.
  17  */
  18
  19
  20 #include "config.h"
  21 #include <math.h>
  22 #include "babl-internal.h"
  23
  24 #define PIXELS       6
  25 #define TOLERANCE    0.000001
  26
  27 float source_buf [PIXELS * 3] =
  28 { 0.0,   0.0, 0.0,
  29   0.5, 0.5, 0.5,
  30   1.0, 1.0, 1.0,
  31   1.0, 0.0, 0.0,
  32   0.0, 1.0, 0.0,
  33   0.0, 0.0, 1.0 };
  34
  35 float reference_buf [PIXELS * 3] =
  36 { 0.0,        0.0,       0.0,
  37   0.735357, 0.0,       0.0,
  38   1.0,      0.0,       0.0,
  39   0.299,    -0.168736, 0.5,
  40   0.587,    -0.331264, -0.418688,
  41   0.114,    0.5,       -0.081312 };
  42
  43
  44 float destination_buf [PIXELS * 3];
  45
  46 static int
  47 test (void)
  48 {
  49   const Babl *fish;
  50   int   i;
  51   int   OK = 1;
  52
  53   fish = babl_fish (
  54     babl_format_new (
  55       babl_model ("RGB"),
  56       babl_type ("float"),
  57       babl_component ("R"),
  58       babl_component ("G"),
  59       babl_component ("B"),
  60       NULL
  61     ),
  62     babl_format_new (
  63       babl_model ("Y'CbCr"),
  64       babl_type ("float"),
  65       babl_component ("Y'"),
  66       babl_component ("Cb"),
  67       babl_component ("Cr"),
  68       NULL
  69     )
  70          );
  71
  72   babl_process (fish, source_buf, destination_buf, PIXELS);
  73
  74   for (i = 0; i < PIXELS * 3; i++)
  75     {
  76       if (fabs (destination_buf[i] - reference_buf[i]) > TOLERANCE)
  77         {
  78           babl_log ("%2i (%2i%%3=%i, %2i/3=%i) is %f should be %f",
  79                     i, i, i % 3, i, i / 3, destination_buf[i], reference_buf[i]);
  80           OK = 0;
  81         }
  82     }
  83   if (!OK)
  84     return -1;
  85   return 0;
  86 }
  87
  88 int
  89 main (void)
  90 {
  91   babl_init ();
  92   if (test ())
  93     return -1;
  94   babl_exit ();
  95   return 0;
  96 }