1 files changed, 86 insertions, 0 deletions
diff --git a/src/vu-transpose.c b/src/vu-transpose.c
new file mode 100644
index 0000000..09fe4b8
--- /dev/null
+++ b/src/vu-transpose.c
@@ -0,0 +1,86 @@
+/* See LICENSE file for copyright and license details. */
+#include "arg.h"
+#include "stream.h"
+#include "util.h"
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+
+static void
+transpose(const struct stream *stream, const char *restrict buf, char *restrict image)
+{
+	size_t x, y, i, b = 0, h, w;
+	w = stream->width * (h = stream->height * stream->pixel_size);
+	for (y = 0; y < h; y += stream->pixel_size)
+		for (x = 0; x < w; x += h)
+			for (i = 0; i < stream->pixel_size; i++)
+				image[x + y + i] = buf[b++];
+}
+
+static void
+usage(void)
+{
+	eprintf("usage: %s\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct stream stream;
+	char *buf, *image;
+	size_t ptr, n;
+	ssize_t r;
+
+	ARGBEGIN {
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc)
+		usage();
+
+	stream.file = "<stdin>";
+	stream.fd = STDIN_FILENO;
+	einit_stream(&stream);
+	fprint_stream_head(stdout, &stream);
+	fflush(stdout);
+	if (ferror(stdout))
+		eprintf("<stdin>:");
+
+	if (stream.width > SIZE_MAX / stream.pixel_size)
+		eprintf("<stdin>: video is too wide\n");
+	n = stream.width * stream.pixel_size;
+	if (n > SIZE_MAX / stream.height)
+		eprintf("<stdin>: video frame is too large\n");
+	n *= stream.height;
+	if (!(buf = malloc(n)))
+		eprintf("malloc:");
+	if (!(image = malloc(n)))
+		eprintf("malloc:");
+
+	memcpy(buf, stream.buf, ptr = stream.ptr);
+	for (;;) {
+		for (; ptr < n; ptr += (size_t)r) {
+			r = read(stream.fd, buf + ptr, n - ptr);
+			if (r < 0) {
+				eprintf("read %s:", stream.file);
+			} else if (r == 0) {
+				if (!ptr)
+					break;
+				eprintf("%s: incomplete frame", stream.file);
+			}
+		}
+		if (!ptr)
+			break;
+		transpose(&stream, buf, image);
+		for (ptr = 0; ptr < n; ptr += (size_t)r) {
+			r = write(STDOUT_FILENO, image + ptr, n - ptr);
+			if (r < 0)
+				eprintf("write <stdout>");
+		}
+	}
+
+	return 0;
+}