Segmenting natural image into regions is concerned as an essential issue in computer vision. In this paper

a new weighted graph-cut algorithm which uses HSI color model is presented to solve a natural disaster image segmentation problem. Using graph theory

the color image is firstly translated into weighted graph by mapping each pixel into graph node. Weighted function is defined by combining HSI color and pixel distance factors

and Cut criterion is suggested by using region internal differences and region external similarity. The experimental result is provided to show the effectiveness of the algorithm

and the comparison with other methods results are also given in detail.