Image visual quality metrics verification by TID2013: Exploring of mean square error drawbacks

Abstract

Specialized image databases like TID2013, allow quantitative evaluation of adequateness to human perception characterized by mean opinion score (MOS) and a verified full-reference visual quality metric using certain criterions such as rank order correlation coefficients (ROCC). In this paper, we propose modifications of known Spearman and Kendall ROCCs that take into account the fact that MOS for existing databases has been measured with a limited accuracy and is most certainly erroneous (contains “noise component”). For the database TID2013 we have also marked images with practically invisible distortions. This has led to considering criteria for detecting such images. Using a mean square error we also analyze metrics based on alternative norms l1, l3, and l4. Analysis is performed for the database TID2013 and different sensitivity of human vision system (HVS) to distortions in color and intensity is taken into account. One approach to analyze adequateness of metrics for different types of distortions is described and proved exploitable.