🚀 go-pugleaf

In article <1992Aug28.223922.11107@eagle.lerc.nasa.gov> ttcain@vangogh.lerc.nasa.gov (Maureen Cain) writes:

   I have an image that was taken through a microscope of a lead sample.
...
   median filter.  I need to get a closed contour from the image as if I took a
   pencil and traced it off the image.  

	   Is there a way to segment the image using contrast and variance 
   stats rather than using and edge detector? Or a combination of both?  Any
   help would be appreciated.  Thanks

The traditional way, which even works sometimes :-), is to use difference
of gaussian (or DOG) filters.  The basic premise is to size two
lowpass operations such that subtracting the two filtered images
results in a bandpass image retaining the object with the desired
spatial dimensions.  The absolute and relative size of the bandpasses
is therefore important.   

A reasonably good approximation is to take the difference of two
box-car filters (rectangles). The math is not as nice as the gaussian
filters but the programming is fairly trivial.

After thresholding, morphological operations can then clean up the
resulting image.
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   John C. Schultz   +1 (612) 733-4047   schultz@halley.serc.3m.com
   How to include the taste of Glendronach in a multi-media system?