ZM_CAPTURES_PER_FRAME

mycal · Post by **mycal** » Tue Aug 01, 2006 4:14 am

Is there any way we can get finer grain resolution on this setting?

It seems like a small sleep after changing channels, maybe from 0-255 Ms would be ideal here.

The reason is that going from 1 to 2 hammers the frame rate output of the board when the setteling time needed may be a fraction of a frame read time.

Anyway just an idea to try to keep as much frame rate on the cheap single chip boards as possible without that jags.

Thanks,

Mycal

jameswilson · Post by **jameswilson** » Tue Aug 01, 2006 9:02 am

The timing issue of the 'round robin' feature that allows you to capture multi inputs is critical. If you are getting combing effect check you are using the right driver for your card. I usually use single chip cards and dont have the problem

lazyleopard · Post by **lazyleopard** » Tue Aug 01, 2006 10:24 am

mycal wrote:Is there any way we can get finer grain resolution on this setting?

No. It is by nature counted in whole frames. However, you should only need it set higher than 1 if:

You are using a capture card that shares one capture chip between two or more inputs,
and you are using a resolution greater than 320x240 (for NTSC) or 384x288 (for PAL),
and you see combing effects on stationary objects caused by wrong-order interlacing

jameswilson · Post by **jameswilson** » Tue Aug 01, 2006 7:05 pm

ah i see i never go above 288 thats why i never see it! thanks for the info

mycal · Post by **mycal** » Thu Aug 17, 2006 5:51 pm

Yea I understand how the card works, but if you switch the port and instead of reading a frame, you wait a small amout of time, the hardware settaling will occure, the question is do you need to read a frame for this settaling to occure or is just a time based thing. If the latter you could probably speed up the framerate quite a bit by not having to wait a full frame read time before you get clean video.

mycal

jameswilson · Post by **jameswilson** » Thu Aug 17, 2006 11:13 pm

if you dont wait for a full frame your gonna strat you capture at line 166 for example not line 1. You obviously have to start at line 1 if when its stablised its currently at 166 it has to wait the full 625 before styarting to grab the frame

mycal · Post by **mycal** » Tue Aug 29, 2006 12:15 am

Ohh, yea your right, didn't think about that.

Thanks,

Mycal

jameswilson · Post by **jameswilson** » Tue Aug 29, 2006 12:23 am

no probs mate, there obvioulsy is something that can be done but i think it needs to be done by bttv driver as its that that gives the images to zm

ZoneMinder Forums

ZM_CAPTURES_PER_FRAME

ZM_CAPTURES_PER_FRAME

Re: ZM_CAPTURES_PER_FRAME