FUNCTION	CRAYFIX,im0,n=n,threshold=threshold

;Identify NxN-pixel cosmic rays events in image and replace with median
;  of surrounding pixels using subroutine BPIXFIX.
;Create AHB 02/04

  if not KEYWORD_SET(n) then n=1
  if not KEYWORD_SET(threshold) then threshold=10.0

  npix = N_ELEMENTS(im0)
  dev = im0 - MEDIAN(im0,n+2)		;subtract boxcar median
  sig = SQRT(TOTAL(dev^2) / (npix-1.))	;std. dev. (mean = 0)
  w = WHERE( ABS(dev) gt threshold*sig)	;ID those above threshold

  if w[0] ne -1 then begin
    bpix = BYTE(im0)
    bpix[*] = 0B
    bpix[w] = 1B
    im1 = BPIXFIX(im0,bpix)
  endif else im1 = im0

RETURN,im1
END