MOVING MEDIAN FILTERS FOR AREA-DETECTOR-DATA

Moving median and center-weighted median tilters are employed to remov e impulse noise from two-dimensional area-detector data. Two generaliz ed mean filters, which have been used previously in crystallographic d ata reduction, are compared with median filters. Examination of the sm oothed data indicates that the median filters are preferred, in this w ork, over the generalized mean filters, for data with a high frequency of impulse noise. Like the generalized mean filters, the median filte rs are useful for eliminating the sharp features (spikes, holes etc.) in the area-detector data while retaining the broader peak-like featur es.