read_image (Image, 'small_ic')
get_image_pointer1 (Image, Pointer, Type, Width, Height)
dev_close_window ()
dev_open_window (0, 0, Width*5, Height*5, 'black', WindowHandle)
dev_display (Image)
gray_histo (Image, Image, AbsoluteHisto, RelativeHisto)
Sigma := 2
MinThresh := 0
while (|MinThresh|#3)
    histo_to_thresh (AbsoluteHisto, Sigma, MinThresh, MaxThresh)
    Sigma := Sigma+0.2
endwhile
dev_set_colored (12)
threshold (Image, Region, MinThresh, MaxThresh)