Abstract: Aiming at the drawbacks existing in the FCM algorithm of the slow speed of operation,result vulnerable to the initial value and the difficulty to deal with the inherent Rician noise of MR image,this paper presented a fast FCM algorithm combined with non-local means．The core of the algorithm is as follow．Firstly,aiming at the Rician noise exi-sting in the MR image,using the non-local means algorithm to deal with the noise,eliminating the impact of noise on segmentation result．Secondly,getting the initial cluster centers automatically according to the proposed rules of initial centers .Finally,the cluster centers should be as the initial cluster centers of fast FCM for the segmentation of the denoised image to solve the slow search speed and the problem that is easy to fall into local minima caused by the random selection of the initial clusters．Experimental results show that the proposed algorithm can quickly and efficiently segment the image,and is more robust to noise.

Key words: Fast FCM algorithm,Medical MR image segmentation,Rician noise,Non-local means