A modified PSNR metric based on HVS for quality assessment of color images

Objective assessment of the image quality is of keen importance in numerous image processing applications. Various objective quality assessment indexes have been developed for this purpose, of which Peak signal-to-noise ratio (PSNR) is one of the simplest and commonly used. However, it sometimes fails to give result similar to as perceived by the Human Visual System (HVS). This paper presents a modified PSNR metric which is based on HVS characteristics and correlates well with the perceived image quality. It takes into account the error sensitivity, structural distortion and edge distortion in the image. The proposed metric uses RGB model for color images and empirically combine the effects of above distortion types on each of the color plane. Simulation results illustrate the precision and efficiency of the proposed metric in assessing the quality of color images for different types of degradations and show better correlation with the known characteristics of HVS in comparison to conventional PSNR metric.