An Efficient Class of Alternating Sequential Filters in Morphology

phological openings and closings. The class of alternating filters (AFs), composed of morphological openings and In this note, an efficient class of alternating sequential filters (ASFs) in mathematical morphology is presented to reduce the closings, has been demonstrated to be useful in image computational complexity in the conventional ASFs about a analysis applications. Sternberg [3] introduced a new class half. The performance boundary curves of the new filters are of morphological filters called alternating sequential filters provided. Experimental results from applying these new ASFs (ASFs), which consist of iterative operations of openings to texture classification and image filtering (grayscale and biand closings with structuring elements of increasing sizes. nary) show that comparable performance can be achieved Transformations that apply alternating sequences of openwhile much of the computational complexity is reduced. ings and closings introduce less distortion than individual  1997 Academic Press openings and closings with the largest structuring element [2]. Schonfeld and Goutsias [4] have shown that ASFs are the best in preserving crucial structures of binary images in