Performance Evaluation of Distortion Measures for Retinal Images

Abstract

Evaluating the quality of processed retinal images is an important issue in applications such as telemedicine. The traditional image quality measures are having limitation in emphasizing the loss of clinically significant information. We previously proposed a wavelet weighted blood vessel distortion measure (WBVDM) for retinal images. The WBVDM gives more importance to the distortion in clinical features (blood vessels) and less importance to the clinically nonsignificant distortion. This paper presents a statistical evaluation of the performance of a number of image quality measures in quantifying the distortion in retinal images. The measures are then investigated in terms of their correlation with subjective evaluation using the Pearson linear correlation coefficient (PLCC) and Spearman rank order correlation coefficient (SROCC). Their statistical behavior is also evaluated in terms of how discriminating they are to distortion artifacts when tested on a variety of images using the analysis of variance (ANOVA) method. The experimental results indicate that WBVDM performs better by showing higher values of PLCC, SROCC and ANOVA analysis. General TermsMedical image analysis