“Fast Template Matching of Designated Regions Based on Polynomial Approximation”

Fast and accurate image retrieval is an essential technology for a surveillance system, and it can be used for many applications such as the robot vision and the content retrieval. Given an input image and a reference image, we focus on the problem of finding the most similar partial image to the reference image in the input image. The template matching is one of the fundamental techniques for the image retrieval. One of the drawbacks of the template matching is the high computational complexity. In this paper, we propose a method for speeding up the calculation of the template matching by approximating the reference image by a polynomial. An existing fast template matching method that uses the polynomial approximation can calculate similarities of all the partial images efficiently, whereas it is not adequate for calculating some designated partial images. In the proposed method, given an input image, the normalized cross correlations of the template and the designated partial images of the input image are calculated efficiently with the polynomial. Experimental results with various sizes of images show the effectiveness of the proposed method.