A new threshold decomposition architecture is introduced to implement stack
filters. The architecture is also generalized to a new class of nonlinear
filters known as threshold decomposition (TD) filters which are shown to be
equivalent to the class of L1-filters under certain conditions. Another ne
w class of filters known as linear and order-statistic (LOS) filters result
from the intersection of the class of TD and L1-filters. Performance compa
rison among several filters are then presented. It was found that TD is com
patible with L1, LOS, and linear filters in suppressing Gaussian noise, and
is superior in suppressing salt-and-pepper noise. LOS filters, however, pr
ovide a better compromise in performance and complexity.