A New Method for Image Retrieval Based on Moment Invariants and Its Application in Education

Shape-based image retrieval is an important part of image retrieval. According to the shape of moment invariant features of image, a new method for shape based image retrieval is presented. Firstly the edges in the original image by using Canny operator are detected, the moment invariants of the edge map are calculated, and the moment invariants as the shape features are automatically indexed. Then, the similarity metrics to accelerate the match are redefined. Finally, the aspect ratio was defined to improve the retrieval precision. Experimental results show that the new method can remove some irrelevant information related to shape in the original image and weaken its influence on the retrieval results to some extent. This new method is simple and efficient and it is of some practical significance. This image retrieval system for education has made a good search result.