linemask

function linemask( clip c, int "blur", int "thresh", int "str" )
{
    blur=default(blur,5)
    thresh=default(thresh,4)
    str=default(str,16)
    mt_lutxy(c,c.binomialblur(blur,u=1,v=1),"x "+string(thresh)+" + y < y x - "+string(str)+" * 0 ?")
}