Rotation Invariant Image Matching by Using Adaptive Concentric Ring Template

Abstract

This paper proposed a method to search a target image area that has a free location and inclination in an objective image. The gray-level histogram and the gray-level ratio of pixels pair histogram are used as the invariant feature to change of inclination in this method. The proposed method separates a circular template to ring regions with the common center and generates histograms about each separated ring region. These generated histograms are used for matching. Moreover, in order to reduce the computation cost with maintaining the reliability, effective ring regions for matching are selected by the genetic algorithm. The experimental results show that the target image areas were searched successfully in spite of some ring regions were not used and the high-speed matching was realized by using the generated concentric ring template image in comparison with by using the whole template image.