Change max white color

[anton_foy]

Hi, is there a quick and simple way to change max white color to black?
Even would like to expand spatially so the neighbouring pixels of the max white area also gets black.
Right now I do it like this:

function b_edge(clip c, int "thresh", int "br")
{
bemask = c.mt_binarize(threshold=thresh).mt_expand().removegrain(20,-1)
blc = c.levels(0,1,255*256,0,(br*256))
mt_merge(c,blc,bemask,y=3,u=1,v=1)
return last
}

But it is quite slow.

[Dogway]

You can use this:

br=0
ex_binarize(200,hi=br,lo=-1,smooth=false,UV=1)

Spotted some issues with function, so here's the updated version for the time being: https://pastebin.com/v0gwdgDg

[anton_foy]

You can use this:

br=0
ex_binarize(200,hi=br,lo=-1,smooth=false,UV=1)

Spotted some issues with function, so here's the updated version for the time being: https://pastebin.com/v0gwdgDg

Wow thanks Dogway I will try it out today.

[Dogway]

Had some time so I finished (https://github.com/Dogway/Avisynth-Scripts/blob/e4527c08b107efd4598a425b2421ac34cc8345ca/ExTools.avsi#L769)it, and optimized further (code was convoluted).
Might not be the very exact thing but you can give it a try, now also working with smooth=true for a clean transition.