Abstract: This paper presented a new image threshold segmentation method based on improved two-dimensional Renyi entropy. First, two-dimensional histogram was build according to gray value and gradient value of the pixels, on this basis, calculated two-dimensional Renyi entropy of target and Background region, at last, we got segmentation threshold by maximizing the Renyi entropy function. It can handle more types of images and get more accurate shape of the image edge that pixels gradient information in combination with parameter of Renyi entropy which is adjustable.

Key words: Image segmentation,Two-dimensional histogram, Renyi entropy,Threshold selection