Interaction with web cam

hi!
me and my friend are planing to build interactive instalation in one club in zagreb and we will need some help :)
we will use vvvv to generate some visuals and super colider (maybe pd) for sound.
there is no problem to generate video…
input will be video signal from web cam.
for now the main problem is motion detection, has anybody use vvvv for this?
i mean only vvvv, i saw some projects here and on the old board but they use eyesweb.
i’ve made some patches that use pipet node to read pixel changes but it’s a bit slow when using high resolution.
i saw that there is a freeframe node for motion detection but i don’t understand it pretty good. did anybody use it for something like this?

and another problem is with cameras, where to place them to get the best resoult?
i know it depends on the project set up but if someone has some tips&tricks i would apriciate it! we have some solutions but if someone know for a good source…

it’s a first time we are doing this and we don’t have much experience with this kind of setup’s, so any kind of help is welcome!

cheers!
vedran

Trautner should be the way to go…

hi!
then i’ll use this.
hope it will do what i want

vedran

I realy don’t understand this trautner output…
when i send output from Changed pixels to ioBox(advanced) nothing happens!?
then i used trautner.bmp from help\resources as a mask and send the data to ioBox with 16x16 colums&rows. the resoult is something i realy don’t understand…
boxes are trigered in stragne positions… when i move my hand (in front of a camera) on the left side it trigs the boxes on the upper half of it…
can someone tell me how are this pixels ordered in the output?
please i’m realy stuck here…

vedran

have you consulted the helppatch already? i really thought it explains it there

hi Joreg!
i’ve try the help patch…
It sez:
“In the bitmap you define areas of interest via shades of gray. For now you can therefore distinguish between movement in 256 areas”

how can i define area of the interest with the shades of gray? that is not clear too
meay be output pin would be more clear to me when i get that.
please help!

vedran

okok.

you have to create the bitmap in a paint-software. make a .bmp the size of the video you are using (e.g. 320x240). then say you want to distinguish between movement in the left half of the image and the right half. therefore you color the left half of the bitmap with one shade of gray. and the right half with an other. then load it into trautner.

one output gives you a pixelcount per each of the 256 grayscales. so in the example above you should get a spread of 254 0s and two slices showing the amount of pixels found in the image of the corresponding grayscale.

the other spread then gives you the amount of changed pixels in the same slices.
cool?

cool joreg!

did’nt try it yet, but now i see…
will post the resoult

hi!
it’s working!!!
realy nice thing, i think i’ll have a loot of fun with it…
will keep you posted!

vedran

i’ve try boygrouping yesterday and it is workin great!