summaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-02-02 19:26:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-02-02 19:26:06 -0800
commit9e6235e997bf091326b2f3ac92217c2ac2e27eb5 (patch)
treed6f754ba270f53edb87ccdd90571b52a913c6e27 /Documentation
parent5c350d93ff4736086a1b08fef1d0b5e22138d2e0 (diff)
parent67e70baf043cfdcdaf5972bc94be82632071536b (diff)
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (45 commits) V4L/DVB (10411): s5h1409: Perform s5h1409 soft reset after tuning V4L/DVB (10403): saa7134-alsa: saa7130 doesn't support digital audio V4L/DVB (10229): ivtv: fix memory leak V4L/DVB (10385): gspca - main: Fix memory leak when USB disconnection while streaming. V4L/DVB (10325): em28xx: Fix for fail to submit URB with IRQs and Pre-emption Disabled V4L/DVB (10317): radio-mr800: fix radio->muted and radio->stereo V4L/DVB (10314): cx25840: ignore TUNER_SET_CONFIG in the command callback. V4L/DVB (10288): af9015: bug fix: stick does not work always when plugged V4L/DVB (10287): af9015: fix second FE V4L/DVB (10270): saa7146: fix unbalanced mutex_lock/unlock V4L/DVB (10265): budget.c driver: Kernel oops: "BUG: unable to handle kernel paging request at ffffffff V4L/DVB (10261): em28xx: fix kernel panic on audio shutdown V4L/DVB (10257): em28xx: Fix for KWorld 330U Board V4L/DVB (10256): em28xx: Fix for KWorld 330U AC97 V4L/DVB (10254): em28xx: Fix audio URB transfer buffer race condition V4L/DVB (10250): cx25840: fix regression: fw not loaded on first use V4L/DVB (10248): v4l-dvb: fix a bunch of compile warnings. V4L/DVB (10243): em28xx: fix compile warning V4L/DVB (10240): Fix obvious swapped names in v4l2_subdev logic V4L/DVB (10233): [PATCH] Terratec Cinergy DT XS Diversity new USB ID (0ccd:0081) ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/video4linux/v4lgrab.c25
1 files changed, 17 insertions, 8 deletions
diff --git a/Documentation/video4linux/v4lgrab.c b/Documentation/video4linux/v4lgrab.c
index 079b628481cf..d6e70bef8ad0 100644
--- a/Documentation/video4linux/v4lgrab.c
+++ b/Documentation/video4linux/v4lgrab.c
@@ -4,12 +4,21 @@
*
* Compile with:
* gcc -s -Wall -Wstrict-prototypes v4lgrab.c -o v4lgrab
- * Use as:
- * v4lgrab >image.ppm
+ * Use as:
+ * v4lgrab >image.ppm
*
* Copyright (C) 1998-05-03, Phil Blundell <philb@gnu.org>
- * Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c
- * with minor modifications (Dave Forrest, drf5n@virginia.edu).
+ * Copied from http://www.tazenda.demon.co.uk/phil/vgrabber.c
+ * with minor modifications (Dave Forrest, drf5n@virginia.edu).
+ *
+ *
+ * For some cameras you may need to pre-load libv4l to perform
+ * the necessary decompression, e.g.:
+ *
+ * export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so
+ * ./v4lgrab >image.ppm
+ *
+ * see http://hansdegoede.livejournal.com/3636.html for details.
*
*/
@@ -24,7 +33,7 @@
#include <linux/types.h>
#include <linux/videodev.h>
-#define FILE "/dev/video0"
+#define VIDEO_DEV "/dev/video0"
/* Stole this from tvset.c */
@@ -90,7 +99,7 @@ int get_brightness_adj(unsigned char *image, long size, int *brightness) {
int main(int argc, char ** argv)
{
- int fd = open(FILE, O_RDONLY), f;
+ int fd = open(VIDEO_DEV, O_RDONLY), f;
struct video_capability cap;
struct video_window win;
struct video_picture vpic;
@@ -100,13 +109,13 @@ int main(int argc, char ** argv)
unsigned int i, src_depth;
if (fd < 0) {
- perror(FILE);
+ perror(VIDEO_DEV);
exit(1);
}
if (ioctl(fd, VIDIOCGCAP, &cap) < 0) {
perror("VIDIOGCAP");
- fprintf(stderr, "(" FILE " not a video4linux device?)\n");
+ fprintf(stderr, "(" VIDEO_DEV " not a video4linux device?)\n");
close(fd);
exit(1);
}