Basic idea: Using structural elements with a certain shape as a probe to detect the target image, when the probe is constantly moving in the image, the shape of the image and the relationship between parts can be considered, so as to obtain information about the morphological and structural characteristics of the image, and then achieve the purpose of analyzing and identifying the image. It is suitable for all aspects related to image processing, such as target recognition, image segmentation, skeleton extraction and image coding and compression, image reconstruction, particle analysis and so on.