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PV-183 at 640x480x24 bit color...?

Posted: Sun Jul 08, 2007 8:01 pm
by nakedfarmanimals
I just got a PV-183 (8v+8a, 240fps) card from bluecherry, with two of the Topica TP-550TVL-DN cameras for testing a system that I will ship in the next 2 weeks.

I can make the following happen:

640x480x8 bit B/W
320x240x24 bit color

I believe that this card can do 640x480x24 bit color, at a rate approaching 20fps. I do not believe that I am processor constrained (maximum loads have been 2.0-3.0) and definitely not storage constrained.

The camera can do 550+ lines, and I have tried the 811x508 NTSC resolution as well.

Has anyone else run into this problem?

Thanks again in advance.

Posted: Sun Jul 08, 2007 9:47 pm
by jameswilson
i would suggest looking at your logs, and id bet you have shmget issues. If so see the wiki

Posted: Mon Jul 09, 2007 12:02 am
by nakedfarmanimals
I'll take that bet!

I have 2GB memory in the machine... using the example numbers in the wiki only sets shared memory at 134217728b, or 128kb (128*1024*1024.) Setting it higher, say at 1GB or 1073741824b (1024^3) and things get nicer for large pictures and color.

Additionally, I set the max frame rates to 20 instead of 30, and decreased the pre and post event buffers to 20. Now it is working great!

Another question... trying to film something moving always presents challenges... what type of challenge gives me the "jaggies" in the below:

Image

Is this something that I can relieve in computer hardware, computer software, or camera hardware / optics?

Both man and dog look like they are vibrating at a high rate of speed...

Thanks again.

Posted: Mon Jul 09, 2007 1:14 am
by cordel
That is called interlacing and happens with anything larger than 320x240. Not much that you can do for it. Google for interlacing:
http://neuron2.net/LVG/interlacing.html
http://en.wikipedia.org/wiki/Interlace