ZoneMinder Forums

With each motion detect alarm I want to capture 10 seconds before, and 10 seconds after each event. What I want to know though, as I cant see it in the readmy, is which value the pre and post event buffer actually uses.

My camera's are limited to 10fps while analysing, then unlimited, which is 25fps when recording an alarm. So, will the 10 seconds before the alarm triggers recorded by zonealarm at 10 or 25 fps, and will the 10 seonds after the alarm has ended keep running at 25fps or will it drop back to 10fps?

You will get 10fps before and after the alarm. Whilst in alarm state you will get up to 25fps. So for 10 secopnds before and after you will need pre and post event buffers of at least 100. Only the pre-event buffer is a true buffer however so you will need to ensure that your ring buffer is at least as big as your pre-event buffer plus a contingency of 20% or so. The post event buffer is (nowadays) just a count so that can be as big as you like.

When enlarging true buffers it's best to make sure you restart ZM and close any streaming windows after each change to allow the shared memory segment to be regenerated. Also check in the logs for shared memory errors as you may need to tweak your system config to accomodate the larger segments.

Phil