Flickering overlay

[Doug Asselbergs]

I’m having a problem with overlays flickering on an image from a 1394 camera.  It started when I “upgraded” to IMAQ 3.5.1 from 3.5.0.  I upgraded because I was trying to figure out why another computer was having the same problem, and this version was the only difference.  Now I can’t get rid of the flickering at all.  I’ve uninstalled IMAQ and Vision as well as uninstalling and reinstalling the Vision RTE but the flickering stays.  It seems that the installer has installed something that it didn’t want to uninstall. 

So short of uninstalling everything and starting from scratch (which may not even work if everything doesn’t really get uninstalled), does anybody have any ideas of how to fix it?  I’d rather not have to format my hard drive again.

The flickering happens in both the vi and the built exe file.  I’m running Labview 8, Vision 7.0 (though the IMAQ 3.5.1 upgrade seemed to install some Vision 8 stuff, not sure why), IMAQ 3.5.1, IMAQ1394 2.0.1.  Upgrading to Vision 8 is not an option because all the bugs in the NI software like this has my company unwilling to invest more unless I can get some proven reliability.

Thanks,

Doug

[T_Marsh]

Hello Doug,

Normally when overlays are flickering it is a symptom of an incompatible or partially incompatible display driver which causes updates to happen poorly.  I would recommend going to the manufacturers site for your video card, or motherboard if it is built in, and try and getting the most recent version of their driver.  This will often help solve all sorts of flickering problems.  If you already have this or if this doesn't help, then I would try and roll back the driver to version 3.5.0.  Version 3.5.0 of the driver is only currently available from the driver CD that came with LabVIEW 8 so let me know if you have any problems getting that driver CD.  The x.x.1 releases are almost always patches and this case is no exception.  That is good news for us in because when you uninstall the driver it won't leave any traces behind.  It should be a clean install if you do decide to go that route.

I hope this helps, and let me know if you run into any difficulties along the way.

Cheers,

[Doug Asselbergs]

Thanks.  It isn’t related to the video driver.  In troubleshooting the one computer with the problem, my computer was working fine until I installed IMAQ 3.5.1 when it started having the same problems.

Actually, I just finished uninstalling all the Vision, IMAQ, and IMAQ1394.  The problem still existed and I found that NIVision.dll and NIVisSvc.dll (in windows\system32) did not get removed by the uninstaller.  Manually removing them and then reinstalling all the above software is what seemed to do the trick.

I suspect that since you can’t get just IMAQ 3.5.1 by itself since it’s part of the Vision 8 package, there was something about this version that isn’t happy with vis written in Vision 7.  Some sort of backwards compatibility issue.

Thanks for your help.

Doug

[T_Marsh]

Hey Doug,

I'm glad to hear you're up and running now.  I tried out installing Vision 7 with the 3.5.1 driver on a computer over here to see if I could reproduce the flickering over here.  I unfortunately didn't have any luck making it flicker.  I wouldn't rule out a weird interaction between the drivers with LabVIEW 7 but it doesn't seem to be consistently reproducible, at least not for me.  If you have any more thoughts on what I could do to try and make it reproducible over here I would be willing to try.

Regards,

Message Edited by Travis M on 05-26-2006 09:46 AM