[babl] tests: add a test verifying that buffers are converted between RGB spaces

[Øyvind Kolås <ok src gnome org>]

commit e07f0e02458dd17ddf7a47592516748237bc55b3
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri Aug 18 23:31:59 2017 +0200

    tests: add a test verifying that buffers are converted between RGB spaces

 tests/Makefile.am      |    1 +
 tests/chromaticities.c |   77 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 0 deletions(-)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 0db0ccd..4c3841f 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -6,6 +6,7 @@ endif
 
 C_TESTS =                              \
        grayscale_to_rgb        \
+       chromaticities          \
        rgb_to_bgr              \
        rgb_to_ycbcr            \
        srgb_to_lab_u8          \
diff --git a/tests/chromaticities.c b/tests/chromaticities.c
new file mode 100644
index 0000000..2c8364a
--- /dev/null
+++ b/tests/chromaticities.c
@@ -0,0 +1,77 @@
+/* babl - dynamically extendable universal pixel conversion library.
+ * Copyright (C) 2005, 2017 Øyvind Kolås.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+#include <math.h>
+#include "babl-internal.h"
+
+#define PIXELS       6
+#define TOLERANCE    0
+
+unsigned char source_buf [PIXELS * 3] =
+{ 0,    0,   0,
+  127, 127, 127,
+  255, 255, 255,
+  255, 0.0, 0.0,
+  0.0, 255, 0.0,
+  0.0, 0.0, 255 };
+
+unsigned char reference_buf [PIXELS * 3] =
+{ 0,   0,     0,
+  145, 145, 145,
+  255, 255, 255,
+  255, 43,  6,
+  0.0, 250, 48,
+  25,  34, 251};
+
+unsigned char destination_buf [PIXELS * 3];
+
+static int
+test (void)
+{
+  int i;
+  int OK = 1;
+
+  babl_process (babl_fish (babl_format_with_space ("R'G'B' u8", babl_space("Apple")), "R'G'B' u8"),
+                source_buf, destination_buf,
+                PIXELS);
+
+  for (i = 0; i < PIXELS * 3; i++)
+    {
+      if (abs (destination_buf[i] - reference_buf[i]) > TOLERANCE)
+        {
+          babl_log ("%2i (%2i%%3=%i, %2i/3=%i) is %i should be %i",
+                    i, i, i % 3, i, i / 3, destination_buf[i], reference_buf[i]);
+          OK = 0;
+        }
+    }
+  if (!OK)
+    return -1;
+  return 0;
+}
+
+int
+main (int    argc,
+      char **argv)
+{
+  babl_init ();
+  if (test ())
+    return -1;
+  babl_exit ();
+  return 0;
+}