关键词: 随机游走, 医学超声图像, 图像分割

Abstract: Owing to the inevitable drawback of speckle noise and weak boundaries in the medical ultrasound images，it is quite difficult to accomplish satisfied segmentation results.The algorithm of random walks is robust to the noise and the fine extracting ability to weak boundary，this paper will apply it to the medical ultrasound image segmentation，merging the information of region and seed points designated by user，with the aid of circuit simulation and combinatorial Dirichlet problem to calculate the probabilities of each of the unseeded points in the image to the seed points of object or background and label the pixel with the maximum probability to it to carry out the segmentation of image.Experiments show that this method can be effective to the segmentation of medical ultrasound images.And in the algorithm，the solution to Dirichlet problem may be computed analytically by solving a sparse，symmetric，positive-definite system of linear equations.So the computing speed is largely improved.

Key words: random walks, medical ultrasound image, image segmentation