blind

commit 3b5aabba0631658af28fa53245e0b71f85fdd1f8
parent 9b496d0545a151b6516ea1240fb3bd6b725ccf40
Author: Mattias Andrée <maandree@kth.se>
Date:   Wed, 11 Jan 2017 01:12:13 +0100

Add vu-crop

Signed-off-by: Mattias Andrée <maandree@kth.se>

Diffstat:
M
Makefile
 | 
1
+
A
src/vu-crop.c
 | 
96
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 97 insertions(+), 0 deletions(-)
diff --git a/Makefile b/Makefile
@@ -5,6 +5,7 @@ BIN =\
 	vu-arithm\
 	vu-colour-srgb\
 	vu-concat\
+	vu-crop\
 	vu-cut\
 	vu-dissolve\
 	vu-extend\
diff --git a/src/vu-crop.c b/src/vu-crop.c
@@ -0,0 +1,96 @@
+/* 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
+usage(void)
+{
+	eprintf("usage: width height left top %s\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct stream stream;
+	char *buf, *image;
+	size_t width = 0, height = 0, left = 0, top = 0;
+	size_t off, y, irown, orown, ptr, n, m;
+	ssize_t r;
+
+	ARGBEGIN {
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc != 4)
+		usage();
+
+	if (tozu(argv[0], 1, SIZE_MAX, &width))
+		eprintf("width be an integer in [1, %zu]\n", SIZE_MAX);
+	if (tozu(argv[1], 1, SIZE_MAX, &height))
+		eprintf("height be an integer in [1, %zu]\n", SIZE_MAX);
+	if (tozu(argv[2], 0, SIZE_MAX, &left))
+		eprintf("left position be an integer in [0, %zu]\n", SIZE_MAX);
+	if (tozu(argv[3], 0, SIZE_MAX, &top))
+		eprintf("top position be an integer in [0, %zu]\n", SIZE_MAX);
+
+	stream.file = "<stdin>";
+	stream.fd = STDIN_FILENO;
+	einit_stream(&stream);
+	if (left + width > stream.width || top + height > stream.height)
+		eprintf("crop area extends beyond original image\n");
+	n = stream.width,  stream.width  = width;
+	m = stream.height, stream.height = height;
+	fprint_stream_head(stdout, &stream);
+	stream.width  = n;
+	stream.height = m;
+	fflush(stdout);
+	if (ferror(stdout))
+		eprintf("<stdout>:");
+
+	if (stream.width > SIZE_MAX / stream.pixel_size)
+		eprintf("<stdin>: video frame is too large\n");
+	n = irown = 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:");
+	m = height * (orown = width * stream.pixel_size);
+	if (!(image = malloc(m)))
+		eprintf("malloc:");
+
+	off = top * irown + left * stream.pixel_size;
+	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;
+
+		for (y = 0; y < height; y++)
+			memcpy(image + y * orown, buf + y * irown + off, orown);
+
+		for (ptr = 0; ptr < m; ptr += (size_t)r) {
+			r = write(STDOUT_FILENO, image + ptr, m - ptr);
+			if (r < 0)
+				eprintf("write <stdout>");
+		}
+	}
+
+	return 0;
+}