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USB camera on but no video displayed, just white screen

Posted: Sat Jan 08, 2011 10:55 pm
by frednet
I'm trying to get zoneminder-1.24.2 running on Gentoo but can't seem to get my USB webcam working. My webcam is reported by lsusb as follows

Bus 001 Device 007: ID 046d:08c2 Logitech, Inc. QuickCam PTZ

which works ok with camorama so I assume it should be ok with zoneminder.
The zoneminder console keeps switching from red to orange along with the 'webcam on' led on the camera repeatedly and my log file zmdc.log reports this as it happens.

08/01/11 22:23:04.619158 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:23:04.619533 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:23:04.620875 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:23:04, pid = 6427]
08/01/11 22:30:20.819739 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:30:25.027047 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:30:25.028536 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:30:25, pid = 6735]
08/01/11 22:38:00.816310 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:38:10.032220 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:38:10.033688 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:38:10, pid = 7089]
08/01/11 22:39:18.636039 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:39:38.068865 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:39:38.070347 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:39:38, pid = 7145]
08/01/11 22:41:49.055188 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:42:29.009849 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:42:29.011274 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:42:29, pid = 7251]
08/01/11 22:45:36.822837 zmdc[6033].ERR ['zmc -d /dev/video0' exited abnormally, exit status 255]
08/01/11 22:46:56.058970 zmdc[6033].INF [Starting pending process, zmc -d /dev/video0]
08/01/11 22:46:56.060439 zmdc[6033].INF ['zmc -d /dev/video0' starting at 11/01/08 22:46:56, pid = 7380]

At no point do I get a picture from the console monitor page, just a blank white area. I've tried doing

zmu -d /dev/video0 -q

and just get as a response

error22

and

zmu -d /dev/video0 -q -v

gives me

Error, failed to query crop /dev/video0: Invalid argument

I'm also getting this text all over the console page

Warning: strftime() [function.strftime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'UTC' for 'GMT/0.0/no DST' instead in /var/www/zoneminder/htdocs/includes/functions.php on line 1412

I've trawled the forum for solutions and although I've found the same problems reported with regards to USB webcams I've yet to find any answers.
Can anyone point me in the right direction?

Posted: Tue Jan 11, 2011 4:13 am
by midian
Your issue sounds like one of the following:

A: either you are not setting the proper native resolution
B: you have not selected the correct color palette
C: your cam might not support video for Linux (there are resources to confirm this on the net)

As a sample, my cheap nightvision usb cam uses the following settings:

Device Path: /dev/video0
Capture Method: Video for Linux version 2
Device Format: NTSC
Capture Palette: YUYV
Width: 1280
Height: 1024

If you are not sure, there are a few different linux console tools to interrogate the cam settings and display them. Once you get the right settings, USB cams do work quite well. Good luck!

Posted: Tue Jan 11, 2011 2:11 pm
by tommy
I had the same problem. Have you tried the latest fix from this thread?
http://www.zoneminder.com/forums/viewto ... c&start=15