Video scrambled on USB camera only

[timbo_nz]

Hi all,

I'm running an installed version of ZM 1.21 live cd which of course is Mandrake 10.1. I was successfully running two different capture cards (bttv & saa7134). Being the tinkerer that I am I purchased a wireless USB video camera and installed it (removing the saa7134 card). The kernel module is usbvision and the whole setup works under xawtv with no problems at all. However only in ZM does the streaming/still video of the USB camera appear compressed, jagged and utterly unrecognisable. I have tried changing all pal/ntsc, b&w/colour etc settings to no avail. Anybody able to shed any light on this one?

[zoneminder]

xawtv uses a straight through memory mapping interface to show video whereas ZM uses a the frame grabber. To test this, try doign a frame capture in xawtv and see if you get the same corruption.

Also it may be useful to post a screen grab if possible.

Phil

[bhomass]

I am not sure if timbo_nz solved his/her problem. I am having the identical problem. xawtv is displaying in frame grab mode ok. so there is something else preventing zoneminder from capturing the video properly. quite possibly, the device has restrictions on resolution which xawtv is able to figure out, but we have to set manually in zoneminder.

I like to post some images of the distorted displays. but how do I post them in this forum?

also, is there an easy way to probe what resolution did xawtv display the camera image at? If I know that, I can try to set zonemiinder to the same res. I tried out v4l-conf, but don't know how to get it dump out the default resolution.

[bhomass]

ok, I found my own answer.

you can use xawtv in the verbose mode with -v 2 option. this printed out the resolution being used.

somehow, xawtv is able to query to workable resolution. for zoneminder, I filled in manually, but don't know how to query for this resolution.