Retinal Fundus Image Enhancement Using the Normalized Convolution and Noise Removing.
Retinal fundus image plays an important role in the diagnosis of retinal related diseases. The detailed information of the retinal fundus image such as small vessels, microaneurysms, and exudates may be in low contrast, and retinal image enhancement usually gives help to analyze diseases related to retinal fundus image. Current image enhancement methods may lead to artificial boundaries, abrupt changes in color levels, and the loss of image detail. In order to avoid these side effects, a new retinal fundus image enhancement method is proposed. First, the original retinal fundus image was processed by the normalized convolution algorithm with a domain transform to obtain an image with the basic information of the background. Then, the image with the basic information of the background was fused with the original retinal fundus image to obtain an enhanced fundus image. Lastly, the fused image was denoised by a two-stage denoising method including the fourth order PDEs and the relaxed median filter. The retinal image databases, including the DRIVE database, the STARE database, and the DIARETDB1 database, were used to evaluate image enhancement effects. The results show that the method can enhance the retinal fundus image prominently. And, different from some other fundus image enhancement methods, the proposed method can directly enhance color images.
Department of Biomedical Engineering, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China.
Peishan
0000-0001-5531-2085
P
Dai
Department of Biomedical Engineering, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China.
Hanwei
0000-0003-1803-5415
H
Sheng
Department of Biomedical Engineering, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China.
Jianmei
0000-0003-1280-026X
J
Zhang
Department of Biomedical Engineering, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China.
Ling
0000-0002-9387-8802
L
Li
Department of Biomedical Engineering, School of Geosciences and Info-Physics, Central South University, Changsha 410083, China.
Jing
0000-0001-7407-2486
J
Wu
Department of Education and Law, Hunan Women's University, Changsha 410004, China.
Min
0000-0001-6992-1949
M
Fan
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