blind

commit 91eae00bfa6abfb4b50833768d54ac48678c88f6
parent d5f9bf804180f50d1a025b3cf70e12238c79cfb3
Author: Mattias Andrée <maandree@kth.se>
Date:   Wed, 31 May 2017 21:06:25 +0200

blind-stack: add -s

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

Diffstat:
M
man/blind-stack.1
 | 
6
+++++-
M
src/blind-stack.c
 | 
11
+++++++----
M
src/stream.c
 | 
4
+++-
M
src/stream.h
 | 
2
+-

4 files changed, 16 insertions(+), 7 deletions(-)
diff --git a/man/blind-stack.1 b/man/blind-stack.1
@@ -3,7 +3,7 @@
 blind-stack - Overlay videos
 .SH SYNOPSIS
 .B blind-stack
-[-b]
+[-bs]
 .IR bottom-stream
 .RI "... " top-stream
 .SH DESCRIPTION
@@ -30,6 +30,10 @@ Instead of drawing the videos on top of each
 other, for each pixel in each frame, print the
 average colour for each input stream's
 corresponding pixel and frame.
+.TP
+.B -s
+The output video will be as long as the shortest
+input video, rather than as the longest.
 .SH SEE ALSO
 .BR blind (7),
 .BR blind-dissolve (1),
diff --git a/src/blind-stack.c b/src/blind-stack.c
@@ -1,7 +1,7 @@
 /* See LICENSE file for copyright and license details. */
 #include "common.h"
 
-USAGE("[-b] bottom-stream ... top-stream")
+USAGE("[-bs] bottom-stream ... top-stream")
 
 #define PROCESS(TYPE, BLEND)\
 	do {\
@@ -42,13 +42,16 @@ main(int argc, char *argv[])
 {
 	struct stream *streams;
 	size_t n_streams, i, frames = 0, tmp;
-	int blend = 0;
+	int blend = 0, shortest = 0;
 	void (*process)(struct stream *streams, size_t n_streams, size_t n);
 
 	ARGBEGIN {
 	case 'b':
 		blend = 1;
 		break;
+	case 's':
+		shortest = 1;
+		break;
 	default:
 		usage();
 	} ARGEND;
@@ -61,7 +64,7 @@ main(int argc, char *argv[])
 
 	for (i = 0; i < n_streams; i++) {
 		eopen_stream(streams + i, argv[i]);
-		if (streams[i].frames > frames)
+		if (shortest ? (streams[i].frames && streams[i].frames) < frames : streams[i].frames > frames)
 			frames = streams[i].frames;
 	}
 
@@ -76,7 +79,7 @@ main(int argc, char *argv[])
 	fprint_stream_head(stdout, streams);
 	efflush(stdout, "<stdout>");
 	streams->frames = tmp;
-	process_multiple_streams(streams, n_streams, STDOUT_FILENO, "<stdout>", process);
+	process_multiple_streams(streams, n_streams, STDOUT_FILENO, "<stdout>", shortest, process);
 
 	free(streams);
 	return 0;
diff --git a/src/stream.c b/src/stream.c
@@ -398,7 +398,7 @@ nprocess_two_streams(int status, struct stream *left, struct stream *right, int 
 
 void
 nprocess_multiple_streams(int status, struct stream *streams, size_t n_streams, int output_fd, const char* output_fname,
-			  void (*process)(struct stream *streams, size_t n_streams, size_t n))
+			  int shortest, void (*process)(struct stream *streams, size_t n_streams, size_t n))
 {
 	size_t closed, i, j, n;
 
@@ -411,6 +411,8 @@ nprocess_multiple_streams(int status, struct stream *streams, size_t n_streams, 
 			if (streams[i].ptr < sizeof(streams->buf) && !enread_stream(status, streams + i, SIZE_MAX)) {
 				close(streams[i].fd);
 				streams[i].fd = -1;
+				if (shortest)
+					return;
 			}
 			if (streams[i].ptr && streams[i].ptr < n)
 				n = streams[i].ptr;
diff --git a/src/stream.h b/src/stream.h
@@ -90,7 +90,7 @@ void nprocess_two_streams(int status, struct stream *left, struct stream *right,
 			  void (*process)(struct stream *left, struct stream *right, size_t n));
 
 void nprocess_multiple_streams(int status, struct stream *streams, size_t n_streams, int output_fd, const char* output_fname,
-			       void (*process)(struct stream *streams, size_t n_streams, size_t n));
+			       int shortest, void (*process)(struct stream *streams, size_t n_streams, size_t n));
 
 void nprocess_each_frame_two_streams(int status, struct stream *left, struct stream *right, int output_fd, const char* output_fname,
 				     void (*process)(char *restrict output, char *restrict lbuf, char *restrict rbuf,