[PD] Gem somewhat more adaptive background subtraction?

Jack jack at rybn.org
Tue Feb 6 21:00:48 CET 2018

Hello Peter,

It is possible to use shaders for this purpose if you don't have to use
only pix_ objects.
For exemple, get the result of a dot product between the normalized
background color and the normalized texels colors. Then use a threshold
to determine if a pixel need to be transparent or not (you can even
smooth this result if needed for a better result).


Le 06/02/2018 à 17:53, Peter P. a écrit :
> Hi list,
> just wondering if anyone has looked into a way to subtract a background
> in Gem pixes using a hybrid approach between frame difference
> [pix_movement] and difference to a static snapshot [pix_background]. I
> want to be able to detect object in front of a background also during
> slow light condition changes or unsupervised operation in say a gallery
> context.
> I can remember that EyesWeb had an adaptive background subtraction, that
> did possibly time-average a series of images to derive the background
> snapshot. Has anyone done anything more fancy in Gem than the two
> wonderful objects above offer?
> thanks for all ideas!
> Peter
> _______________________________________________
> Pd-list at lists.iem.at mailing list
> UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list

More information about the Pd-list mailing list