1 files changed, 116 insertions, 0 deletions
diff --git a/src/blind-mosaic-corners.c b/src/blind-mosaic-corners.c
new file mode 100644
index 0000000..ecb9692
--- /dev/null
+++ b/src/blind-mosaic-corners.c
@@ -0,0 +1,116 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+USAGE("[-xy]")
+
+static size_t pixsize;
+
+static int
+pixcmp(const void *a, const void *b)
+{
+	return memcmp(a, b, pixsize);
+}
+
+static size_t
+count_unique(char *base, size_t n)
+{
+	size_t ret = 1, i;
+	qsort(base, n, pixsize, pixcmp);
+	for (i = 1; i < n; i++)
+		ret += !!memcmp(base + (i - 1) * pixsize, base + i * pixsize, pixsize);
+	return ret;
+}
+
+int
+main(int argc, char *argv[])
+{
+	int tiled_x = 0;
+	int tiled_y = 0;
+	struct stream stream;
+	void *colours[2];
+	char *buf, *corners, *here, *found;
+	ssize_t dl, dr, du, dd;
+	size_t i, j, n, x, y;
+	int v;
+
+	ARGBEGIN {
+	case 'x':
+		tiled_x = 1;
+		break;
+	case 'y':
+		tiled_y = 1;
+		break;
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc)
+		usage();
+
+	eopen_stream(&stream, NULL);
+	echeck_dimensions(&stream, WIDTH | HEIGHT, NULL);
+
+	n = stream.width * stream.height;
+	buf = emalloc(stream.frame_size);
+	corners = emalloc((n + 7) / 8);
+
+	found = alloca(9 * stream.pixel_size);
+	colours[0] = alloca(stream.pixel_size);
+	colours[1] = alloca(stream.pixel_size);
+	memset(colours[0], 0, stream.pixel_size);
+
+	if (!strcmp(stream.pixfmt, "xyza")) {
+		((double *)(colours[1]))[0] = (double)1;
+		((double *)(colours[1]))[1] = (double)1;
+		((double *)(colours[1]))[2] = (double)1;
+		((double *)(colours[1]))[3] = (double)1;
+	} else if (!strcmp(stream.pixfmt, "xyza f")) {
+		((float *)(colours[1]))[0] = (float)1;
+		((float *)(colours[1]))[1] = (float)1;
+		((float *)(colours[1]))[2] = (float)1;
+		((float *)(colours[1]))[3] = (float)1;
+	} else {
+		eprintf("pixel format %s is not supported, try xyza\n", stream.pixfmt);
+	}
+
+	fprint_stream_head(stdout, &stream);
+	efflush(stdout, "<stdout>");
+
+	pixsize = stream.pixel_size;
+	while (eread_frame(&stream, buf)) {
+		memset(corners, 0, (n + 7) / 8);
+		for (i = 0; i < n; i++) {
+			here = buf + i * pixsize;
+			x = i % stream.width;
+			y = i / stream.width;
+			j = 1;
+			memcpy(found, here, pixsize);
+
+			dr = x != stream.width - 1 ? pixsize : tiled_x ? pixsize - stream.row_size : 0;
+			dl = x ? -pixsize : tiled_x ? stream.row_size - pixsize : 0;
+			dd = y != stream.height - 1 ? stream.row_size : tiled_y ? stream.row_size - stream.frame_size : 0;
+			du = y ? -stream.row_size : tiled_y ? stream.frame_size - stream.row_size : 0;
+
+			memcpy(found + j++ * pixsize, here + dr, pixsize);
+			memcpy(found + j++ * pixsize, here + dl, pixsize);
+			memcpy(found + j++ * pixsize, here + dd, pixsize);
+			memcpy(found + j++ * pixsize, here + du, pixsize);
+			memcpy(found + j++ * pixsize, here + dr + du, pixsize);
+			memcpy(found + j++ * pixsize, here + dl + du, pixsize);
+			memcpy(found + j++ * pixsize, here + dr + dd, pixsize);
+			memcpy(found + j++ * pixsize, here + dl + dd, pixsize);
+
+			if (j > 2 && count_unique(found, j) > 2)
+				corners[i >> 3] |= (char)(1 << (i & 7));
+		}
+		for (i = 0; i < n; i++) {
+			v = (corners[i >> 3] >> (i & 7)) & 1;
+			memcpy(buf + i * pixsize, colours[v], pixsize);
+		}
+		ewriteall(STDOUT_FILENO, buf, stream.frame_size, "<stdout>");
+	}
+
+	free(buf);
+	free(corners);
+	return 0;
+}