Prior Guided Fundus Image Quality Enhancement Via Contrastive Learning

Pujin Cheng, Li Lin, Yijin Huang, Junyan Lyu, Xiaoying Tang

Abstract: Fundus images of poor quality may seriously influence clinic judgments. Existing fundus image quality enhancement (FIQE) approaches mainly make use of general image features but no prior domain knowledge. In this paper, we proposed and validated an efficient FIQE method with a prior constraint, named Efficient Prior Contrastive unpaired Generative Adversarial Network (EPC-GAN). Inspired by the contrastive unpaired translation framework, we emphasized local features during the enhancing process via contrastive patchwise samples. Moreover, to utilize high-level features in the fundus domain (such as vessels, optic disc/cup, and even lesions), we designed a fundus prior loss to avoid information modification and over-enhancement. Besides, we presented an efficient network architecture to overcome the high consumption in terms of both time and GPU-memory. Through both qualitative and quantitative experiments on a public dataset EyeQ, we demonstrated the superior performance of our proposed method.