blind

commit 649043d5664744290e4b66bbf1dfd7d12c1537ae
parent 9b14f11d15d355209ef275b36b43bc3ef6c08cd6
Author: Mattias Andrée <maandree@kth.se>
Date:   Mon,  9 Jan 2017 16:13:56 +0100

Add vu-set-luma

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

Diffstat:
A
src/vu-set-luma.c
 | 
124
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1 file changed, 124 insertions(+), 0 deletions(-)
diff --git a/src/vu-set-luma.c b/src/vu-set-luma.c
@@ -0,0 +1,124 @@
+/* See LICENSE file for copyright and license details. */
+#include "arg.h"
+#include "stream.h"
+#include "util.h"
+
+#include <fcntl.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+static void
+usage(void)
+{
+	eprintf("usage: %s luma-stream\n", argv0);
+}
+
+static void
+process_xyza(struct stream *colour, struct stream *luma, size_t n)
+{
+	size_t i;
+	double a;
+	for (i = 0; i < n; i += colour->pixel_size) {
+		a = ((double *)(luma->buf + i))[1];
+		a *= ((double *)(luma->buf + i))[3];
+		((double *)(colour->buf + i))[1] *= a;
+	}
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct stream colour;
+	struct stream luma;
+	ssize_t r;
+	size_t i, n;
+	void (*process)(struct stream *colour, struct stream *luma, size_t n);
+
+	ARGBEGIN {
+	default:
+		usage();
+	} ARGEND;
+
+	if (argc != 1)
+		usage();
+
+	colour.file = "<stdin>";
+	colour.fd = STDIN_FILENO;
+	einit_stream(&colour);
+
+	luma.file = argv[0];
+	luma.fd = open(luma.file, O_RDONLY);
+	if (luma.fd < 0)
+		eprintf("open %s:", luma.file);
+	einit_stream(&luma);
+
+	if (colour.width != luma.width || colour.height != luma.height)
+		eprintf("videos do not have the same geometry\n");
+	if (colour.pixel_size != luma.pixel_size)
+		eprintf("videos use incompatible pixel formats\n");
+
+	if (!strcmp(colour.pixfmt, "xyza"))
+		process = process_xyza;
+	else
+		eprintf("pixel format %s is not supported, try xyza\n", colour.pixfmt);
+
+	for (;;) {
+		if (colour.ptr < sizeof(colour.buf) && !eread_stream(&colour, SIZE_MAX)) {
+			close(colour.fd);
+			colour.fd = -1;
+			break;
+		}
+		if (luma.ptr < sizeof(luma.buf) && !eread_stream(&luma, SIZE_MAX)) {
+			close(luma.fd);
+			luma.fd = -1;
+			break;
+		}
+
+		n = colour.ptr < luma.ptr ? colour.ptr : luma.ptr;
+		n -= n % colour.pixel_size;
+		colour.ptr -= n;
+		luma.ptr -= n;
+
+		process(&colour, &luma, n);
+
+		for (i = 0; i < n; i += (size_t)r) {
+			r = write(STDOUT_FILENO, colour.buf + i, n - i);
+			if (r < 0)
+				eprintf("write <stdout>:");
+		}
+
+		if ((n & 3) || colour.ptr != luma.ptr) {
+			memmove(colour.buf, colour.buf + n, colour.ptr);
+			memmove(luma.buf,  luma.buf  + n, luma.ptr);
+		}
+	}
+
+	if (luma.fd >= 0)
+		close(luma.fd);
+
+	for (i = 0; i < colour.ptr; i += (size_t)r) {
+		r = write(STDOUT_FILENO, colour.buf + i, colour.ptr - i);
+		if (r < 0)
+			eprintf("write <stdout>:");
+	}
+
+	if (colour.fd >= 0) {
+		for (;;) {
+			colour.ptr = 0;
+			if (!eread_stream(&colour, SIZE_MAX)) {
+				close(colour.fd);
+				colour.fd = -1;
+				break;
+			}
+
+			for (i = 0; i < colour.ptr; i += (size_t)r) {
+				r = write(STDOUT_FILENO, colour.buf + i, colour.ptr - i);
+				if (r < 0)
+					eprintf("write <stdout>:");
+			}
+		}
+	}
+
+	return 0;
+}