Alternating sequential operators based on top-hat selection transform

Alternating sequential filters (ASFs) are one class of important morphological filters, which are constructed from the classical opening and closing operations in different ways. Because the classical opening and closing have the defect of image detail smoothing, ASFs may also smooth image details. Top-hat selection transform selectively outputs different image processing results in purpose, which has the ability of image detail protection. Firstly, based on top-hat selection transform, two new operations which could protect image details are constructed and analyzed in this paper. Then, a new class of alternating sequential operators, named SASOs, is proposed based on the two new operations. One application of impulsive noise removal is used to demonstrate the efficiency of SASOs. And, the experimental results show that, SASOs could smooth noises and protect image details. Therefore, SASOs may be widely used in different applications.