Vessels Segmentation Base on Mixed Filter for Retinal Image

The retinal vessels segmentation by computer usually assist doctor to detect diabetic retinopathy. Due to the characteristic of retinal vessels structure is complex and changeable, the automatic vessels segmentation still is a challenging task. In this paper, the Mixed filter method is proposed for the retinal vessels segmentation, which utilizes matched filter (MF) combining B-COSFIRE filter to extract the vessels network. Firstly, the CLAFLE algorithm is used to processe with the green channel of retinal image for enhancing the contrast between blood vessel and background. Then, in the matched filter channel, morphological top-hat and bottom-hat are used to further enhance the contrast and Gaussian kernel is used to to extract the thin vessels tree. At the same time, B-COSFIRE filter is make use of filtering the thick vessels tree for green channel of retinal image. The corresponding results of dual channel filtering are segmented and fused to achieve retinal vessels segmentation map. Experimental results show that the proposed algorithm can effectively improve the performance of retinal vessels segmentation compared with single filtering method.