ZoneMinder Forums

When I set a camera's resolution to 640 x 480, the device colour turns red and it appears to be disabled. There are no images at all.

Are there some circumstances under which ZoneMinder disables a device?

Do you have anything in your logs about shmget ?
It's likely that your server can't handle the memory needed by your new capture resolution.

Be warned that using higher resolution will eat more memory and more bandwith too, it does matters if your cameras are on usb (limited bandwith).

If it's the case, have a look there

Let us know if it works

id agree i would expect it to be shared mem problem and your logs will have someing like cannot shmget..... see the faq regarding this issue

I have checked the faq KaZeR referred to and it mentions a ring buffer of 100. Do the buffers refer to the setting in the Buffer page for the camera's options where it says Image Buffer size or does it include the sum of the other buffer values?

Does the figure of 100 apply for each camera or the combination of all cameras?

I am also using bt878 capture cards and wonder if I can use some of the other capture formats to reduce the memory requirements.

The zm system is an AMD 3200 with 1Gig memory and it has 5 cameras with 4 more planned. What sort of resolution can it handle if I want to capture say 8-12 fps on each channel? It is mainly continous recording.

the ring buffer is a different thing.
The ring buffer keeps a number of images in memeory in a 'ring'
ie if you set it to 40 the ring buffer will hold the last 40 images in ram (at 2 fps the 20 seconds, but at 20 fps its 2 seconds.

You need to check your logs to find out why you cant get images after increasing the image size and restarting. Without that no-one will know what is wrong as it could be one of a thousand things

I raised the shmmax settings and it worked.

Thanks for the help

good stuff!