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RSS >  FPS and Jitter, Problem.
reynal_sf #1 29/04/2008 - 03h31

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Hello guys, and thank you for this great piece of software.

I'm having a little problem. I'm getting 30 FPS but really high jitter (20-30). It really affects my movements, the little red lights seem to turn off and on (Like if it's not transmitting the light as it supposed to.) But if I lower my FPS (20) it will eventually get lower jitter (2-5). Any ideas? Thank you.
didja #2 29/04/2008 - 19h29

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Hi :) ,

I don't really think that your issue is due to jitters. I think there is a problem with the threshold.

FreeTrack surely doesn't see your leds well. Try to adjust the threshold.

Rémy ;)
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reynal_sf #3 29/04/2008 - 23h32

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I don't really understand what do you mean by "threshold." I'm kind of new at this. But what I don't really understand is that with high FPS (30) it will get high Jitters (20-30). But with low FPS (20) it will get low Jitters (1-5). Could you please explain about the threshold? I don't understand what that is--or where to fix it? Thank you.  :pigekedal:
didja #4 30/04/2008 - 00h05

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Quotation from the FAQ :

What does the 'jitter' measurement mean?

Jitter counts the number of frames that deviate more than +/-15% of the average frame rate in a second. It indicates frame rate instability which can potentially cause a reduction in panning smoothness. If the deviation is small FreeTrack, when minimized, may be able to neutralise it, so a high jitter number does not necessarily mean there will be high jitter in the output.



You can have high jitters and good tracking accuracy ;) .

And this what I mean by "threshold" :

Posted Image

Good luck ;) .

Rémy :)
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reynal_sf #5 30/04/2008 - 03h55

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Okay, it still not helping. Look, I made a short clip to make things clearer for you. Just watch it and read the description. (The part that says Note)

http://www.youtube.com/watch?v=40h-2875Zps
Kestrel #6 30/04/2008 - 04h16

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You need to have three green lights at all times with no flickering to red. You've reduced exposure to get 30fps which has reduced the brightness of the points and now they aren't bright enough for reliable tracking. Movement reduces their brightness further so it might be tracking when stationary but not when moving.

*Reduce threshold
*Make points brighter
*Use a weaker visible light filter
*Remove your webcam's IR filter
uscstaylor #7 16/09/2008 - 00h00

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Thank you for that video, By setting my threshold tab, I am at 0 in the Jitters.

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