Strategies in character segmentation: a survey

Abstract

This paper provides a review of advances in character segmentation. Segmentation methods are listed under four main headings. The operation of attempting to decompose the image into classifiable units on the basis of general image features is called "dissection". The second class of methods avoids dissection, and segments the image either explicitly, by classification of specified windows, or implicitly by classification of subsets of spatial features collected from the image as a whole. The third strategy is a hybrid of the first two, employing dissection together with recombination rules to define potential segments, but using classification to select from the range of admissible segmentation possibilities offered by these subimages. Finally, holistic approaches that avoid segmentation by recognizing entire character strings as units are described.