checkborders.avsi

function checkborders(clip c,int "x")
{
x=default(x,32)
c
c00=crop(0,0,x,x)
c01=crop(width()-x,0,x,x)
c10=crop(0,height()-x,x,x)
c11=crop(width()-x,height()-x,x,x)
stackvertical(stackhorizontal(c00,c01),stackhorizontal(c10,c11))
pointresize(4*x,4*x,-x,-x,4*x,4*x)
}