Morphological segmentation under complex backgrounds using enhanced gray-scale hit-or-miss transform

In the process of packaging for integrated circuits or flexible PCBs, special characters are printed to indicate the status of quality control. During the automated inspection process, these characters are detected and indentified by the inspection equipment. The characters are sometimes difficult to be segmented from the images due to the complex backgrounds, which are complex circuit patterns and other graphic features. In this paper, we develop character segmentation algorithm based on grayscale hit-or-miss morphological transformation. The character's width is assumed to be known. Performance of the proposed algorithm is extensively tested, and the results show successful accuracy.