iraf.net

NUMBER:	450
MODULE:	imfilter.fmedian,imfilter.frmedian,imfilter.fmode,imfilter.frmode
SYSTEM:	V2.11
DATE:	Fri Nov 19 14:20:16 MST 1999
FROM:	davis

BUG:	The fast median / mode filtering tasks will overflow producing
	pathological pixel values if the size of the filtering kernel
	xfilter * yfilter > 32767 and the number of pixels in 1 histogram
	bin happens to be > 32767 as may happen in bad pixel regions.

	The problem was due to the fact that for historical reason the
	algorithm histogram was stored as a short instead of an int.

STATUS:	Fixed for 2.11.3. The workaround is to try and keep the filter size
	< 32767 pixels in size, or to use the much slower median task.