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Live vision

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dcole07:
If you have a moving robot, how do you want to have it's vision? If it has to be processed by a program to find objects.

Do you just want a high speed camera to take a pic ever sec, or is there a way to do it with live feed (like a video camera). I know it's generally the same, but it's like .jpg vs. .wmv ... or does it just depend on if your software can break a live feed into images and process it fast enough?

Cognaut:
It depends on the software to reformat and process the data.

My webcams send a rapid succession of jpgs.  The frame rate is adjustable from 1 to 30fps.  The only issue that I have with them is that they're not in sync with each other.

JesseWelling:
not in sync? can we get a more accurate explanation so we gain more experience? ;D

Cognaut:
The webcams each have their own internal clocks, so they snap their frames independently.  This makes the stereo vision more difficult because the left and right frames are not taken at the exact same time.

Increasing the frame rate will reduce the error, but I can't count on two independent webcams for any high speed tracking without some sort of frame/vector interpolation routine.  If the bot is slow moving and the frame rate is high, then the data will be acceptable.

I'd like to take the webcams apart and wire them together somehow, but I hesitate without knowing what I'll find inside.

****

It's possible that the frames are being triggered from within the software drivers.  I'm going to ask the manufacturer about it.

JesseWelling:
wai! :D I'd never even thought of that problem with stereo vision.....

I guess my plan (when I add vision) is to couple a range finding sensor with my camera.
Seems to me the more info you have about the picture you take the better it can be used.

I'm not so interested in Stereo vision I guess...after all you can play a first person shooter
(Half Life, Counter Strike, Halo) with only the illusion of 3d right? I know stereo vision
would help in terms of judging distances and everything, but I don't think it's strictly
necessary... and I think processing would be better spent elsewhere...

Essentialy what you are doing to find or track objects is frame differencing. IE looking
at how frames of the last picture are different from your current one. Video is just a bunch
of pictures so it really depends on the throughput of your system...

One thing to consider is that Jpgs are smaller but they take time to decode...you have to balance
speed of transfer and speed of decodeing...

Cognaut what are you using for processing?

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