High-speed analog optoelectronic image processing systems are generall
y characterized by low accuracy and are not well suited to application
s requiring large dynamic range. We show that the low accuracy of a ty
pical analog optoelectronic convolver can be tolerated in a high-accur
acy application when threshold decomposition is used to perform order-
statistic processing on digitized gray-scale imagery. The robustness o
f the method in the presence of system noise, combined with the parall
elism of the optical convolver, suggests that hybrid analog optical/di
gital electronic processors for order-statistic image processing may b
e attractive alternatives to all-electronic processors. We analyze the
immunity of such a hybrid processor to noise generated by spatial var
iations of emitter and photodetector arrays for the order-statistic op
erations of median filtering, dilation, and erosion.