Abstract: Graph Cuts (GC) is a novel image segmentation method based on graph theory
framework. The innovations of this theory lie in its global optimization and the unity of
knowledge. However, if the image is large, computation will be very time-consuming. This paper
presents a GC-based Hierarchical image segmentation method. First the initial segmentation is
obtained through GC in the low-resolution with a very low computational cost. Then the contour
is projected back to the high-resolution image to construct a narrow band. At last accurate
segmentation in the narrow-band is achieved by using of matting arithmetic. Experimental results
show that this method can ensure the accuracy of segmentation results with a significant
increasing in computing speed.

Key words: information processing technology, image segmentation, graph cuts, multilevel
segmentation, matting