1 files changed, 84 insertions, 0 deletions
diff --git a/test/imagediff.c b/test/imagediff.c
new file mode 100644
index 000000000..36962f11f
--- /dev/null
+++ b/test/imagediff.c
@@ -0,0 +1,84 @@
+/* imagediff - Compare two images
+ *
+ * Copyright © 2004 Richard D. Worth
+ *
+ * Permission to use, copy, modify, distribute, and sell this software
+ * and its documentation for any purpose is hereby granted without
+ * fee, provided that the above copyright notice appear in all copies
+ * and that both that copyright notice and this permission notice
+ * appear in supporting documentation, and that the name of Richard Worth
+ * not be used in advertising or publicity pertaining to distribution
+ * of the software without specific, written prior permission.
+ * Richard Worth makes no representations about the suitability of this
+ * software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ * 
+ * RICHARD WORTH DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN
+ * NO EVENT SHALL RICHARD WORTH BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+ * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Author: Richard D. Worth <richard@theworths.org> */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "buffer_diff.h"
+#include "read_png.h"
+#include "write_png.h"
+#include "xmalloc.h"
+
+int 
+main (int argc, char *argv[])
+{
+    unsigned char *buffer_a;
+    unsigned int width_a, height_a, stride_a;
+    unsigned char *buffer_b;
+    unsigned int width_b, height_b, stride_b;
+
+    unsigned char *buffer;
+    unsigned int width, height, stride;
+    int buffer_size, total_pixels_changed;
+
+    if (argc < 2) {
+	fprintf (stderr, "Usage: %s image1.png image2.png\n", argv[0]);
+	fprintf (stderr, "Computes an output image designed to present a \"visual diff\" such that even\n");
+	fprintf (stderr, "small errors in single pixels are readily apparent in the output.\n");
+	fprintf (stderr, "The output image is written on stdout.\n");
+	exit (1);
+    }
+
+    read_png_argb32 (argv[1], &buffer_a, &width_a, &height_a, &stride_a);
+    read_png_argb32 (argv[2], &buffer_b, &width_b, &height_b, &stride_b);
+
+    if ((width_a == width_b) && (height_a == height_b) && (stride_a == stride_b))
+    {
+	width = width_a;
+	height = height_a;
+	stride = stride_a;
+    } else {
+	fprintf (stderr, "Error. Both images must be the same size\n");
+	return 1;
+    }
+
+    buffer_size = stride * height;
+    buffer = xmalloc (buffer_size);
+    
+    total_pixels_changed = buffer_diff (buffer_a, buffer_b, buffer,
+					width_a, height_a, stride_a);
+
+
+    if (total_pixels_changed)
+	fprintf (stderr, "Total pixels changed: %d\n", total_pixels_changed);
+    write_png_argb32 (buffer, stdout, width, height, stride);
+
+    free (buffer);
+
+    return 0;
+}
+
+
+