Nonlinear filtering of images in optical-digital processors

摘要

Implementations of rank order and morphological filtering in optical-digital processors are reviewed. In the processors, all of the convolutions are performed in inherently parallel optical correlators. Subsequent arithmetic and logic operations are made digitally. In the processors, gray scale images are sequentially treated slice by slice due to the threshold decomposition concept. The optical-digital method of local histogram calculation within both binary and weighted neighborhoods of arbitrary size and shape is recalled. Several configurations of optical correlators are discussed. Finally, some examples of efficient use of hybrid processors are presented.