;+
; NAME: match_filter
; PURPOSE:
; 	Convolve an image with a normalized version of itself.
;
; 	Quick and dirty...
;
; INPUTS:
; KEYWORDS:
; OUTPUTS:
;
; HISTORY:
; 	Began 2005-09-05 20:00:40 by Marshall Perrin 
;-

function match_filter,image,thresh=thresh

	n = image/total(image)
	findmaxstar,n,mx,my
	sz = size(n)
	n = shift(n,sz[1]/2-mx,sz[2]/2-my)

	if n_elements(thresh) gt 0 then n >= thresh

	return,convolve(image,n)

end