Max fps Setting - Image Quality on Channel 1

Ruler · Post by **Ruler** » Mon Oct 10, 2005 10:39 pm

I just ran into an extremely weird problem, but found an easy work-around. (Albeit after an hour of wanting to chuck the machine out the door.

)

I'm setting up a ZoneMinder box built around Slackware 10.1 and ZM 1.21.3 and the Spectra-8 capture card. This is not the first system I've built that fits this description - the others are running fine.

The problem I ran into with this one is that the second input on each chip (channel 1 as opposed to the primary channel 0) shows up as an extremely bled-out white version of the image. Channel 0 is fine, but channel 1 is completely hosed - you can't make out anything. I found that this problem goes away when I set the max fps to 1.00 instead of 0.80 as I have on other systems. (640x480 capturing 24x7 is rough on drive space - a terrabyte RAID array doesn't last that long.)

I've gone through the configuration of the card, zoneminder, bttv module, and even swapped the card for another of the revision as in another machine. The same behavior is evident no matter what I try. xawtv displays the correct image no matter what input is used, which leads me to believe that there's been something changed between 1.21.0 and 1.21.3 that caused this.

I can e-mail pics of a frame captured at each rate if needed; I currently have no publically-accessible web space available, otherwise I'd upload and link to them in this thread.

Post by **zoneminder** » Tue Oct 11, 2005 4:13 pm

You can mail me pictures and I'll put them up here. I don't know offhand what the problem might be. If you have fast capture rates I would have suspected possibly the image not settling before the second capture but you have the opposite.

Phil

Ruler · Post by **Ruler** » Tue Oct 11, 2005 4:40 pm

Mail sent.

What I find most interesting that it doesn't happen on another box running the same config and it only happens on channel 1 of any video device.

Post by **zoneminder** » Thu Oct 13, 2005 8:17 pm

Whoops that reminds to put your images up

Unfortunately I'm none the wiser as to why it might be happening

Phil

jameswilson · Post by **jameswilson** » Thu Oct 13, 2005 8:25 pm

i had something like this on an impact vcb card and it happens when more than 1 input is switching but not connected.

IE ip 1, 2 3

ip 1 has cam and 75 ohm load, 2 and 3 dont

switches to 1 bright image as no load on 2 and 3

fixed it with either creating monitor and selecting none or fit a 75 ohm impedance load to other inputs.

James

Ruler · Post by **Ruler** » Thu Oct 13, 2005 9:36 pm

That could well be the problem with this one, as I mounted all the cameras except one to test the configuration of the server. However that doesn't explain why it only happens in ZM when the FPS is taken down below 1 fps - xawtv is fine, as is zoneminder when the fps is kicked up. I'll update this thread again when the server is installed and has all 8 cameras connected to it - it'll be interesting to see if that solves the problem.

PS - Don't I have an attractive desktop and door?!?

jameswilson · Post by **jameswilson** » Thu Oct 13, 2005 9:41 pm

doesnt xawtv try to run it at 25 fps?

James

Ruler · Post by **Ruler** » Thu Oct 13, 2005 9:59 pm

I couldn't tell you off the top of my head; I'll check when that system is hooked up again, but it's certainly possible.

Post by **cordel** » Fri Oct 14, 2005 3:36 am

xawtv uses a differant method to get the images from the card than zm. ZM uses a capture image method where xawtv goes more direct. I have also come across this issue and generaly is because the insmod options are incorrect for that card. Like James said it seems more prevelent on certain cards and can happen if you have ports enabled with no device on them.
I think this might relate to the chips ability to handle s-video and some combinations make the card think it needs to switch to this mode.
Regards,
Cordel