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Parasite in contour node?

Hi!

I got a problem with the contour node, in fact I think that the problem come from my webcam :
I always got 4 contour detected on each corner of the renderer that don’t match nothing. the problem may come from the webcam’lens, and so can’t be technicaly solved.
That’s why I would like to make the contour node don’t detect contour under a certain binsize value (for example 5), is there a way to do it ?

here is a screenshot of the problem :

http://img371.imageshack.us/img371/5259/74920946md3.jpg

Hello crasse , you can avoid your camera error by selecting the blobs you want , here i show an example , hope it,s helpfull for you .

contour_Select.v4p (25.7 kB)

what about doing a background substraction with trautner before feeding the video into contour? could also improve your tracking stability in general…

Hi !

Thanks a lot colorsound and elektromeier.

I’m using the colorsound way to avoid the problem and it works pretty good ^^
I also tried the Trautner, I made a bitmap mask, to mask corners, it worked but the video was flickering in Black/White so I wasn’t able to track colors from it. Anyway I will use the trautner for another purpose in my work ( to quantify Motion Level from the contour tracked videostream)

So thanks to both of you :)

another technique is mapping the video as a texture on a quad and use AsVideo (EX9.Texture) to put it into tracking nodes.

there is a slight performance penalty for the AsVideo detour, but as soon as you take this route you can do lens corrections, keystoning, rotating, scaling, masking in this way. If you use a shader for displaying the video you could also do color corrections, thresholding, erosion, dilation etc without any additional performance costs. also a great way to stitch two cameras into one tracking scenario.