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I would like to distinguish between "background"]]> Feb 18, 2013 2:07:46 AM Feb 18, 2013 2:07:46 AM avrialony@gmail.com 0 http://mathforum.org/kb/thread.jspa?messageID=8353055&tstart=0#8353055 >]]> Feb 17, 2013 10:36:06 AM Feb 17, 2013 10:36:06 AM imageanalyst@mailinator.com 1 http://mathforum.org/kb/thread.jspa?messageID=8348839&tstart=0#8348839
How can I set NaN in all pixels outside the ring.

note that the pixel values inside the ring and in the]]> Feb 16, 2013 12:47:52 PM Feb 16, 2013 12:47:52 PM avrialony@gmail.com 2