Color-Sensitivity-Based Combined PSNR for Objective Video Quality Assessment

Abstract

The peak signal-to-noise ratio (PSNR) has been widely employed as an objective video quality assessment (VQA) metric. Usually, videos are represented in the YCbCr color space, which results in three PSNR values for each video frame. Several VQA metrics have been proposed to measure the video quality with a single combined PSNR. However, these metrics are derived heuristically without theoretical justification. In this paper, based on our extensive subjective tests on the sensitivity of the human visual system to different color components, we derive the optimal weighting coefficients of a color-sensitivity-based combined PSNR (CSPSNR). Moreover, to verify the performance of the combined PSNR, test sequences with different levels of combined PSNRs are used to evaluate the quality of the videos. However, no such database is currently available for measuring the effectiveness of different methods regarding combined PSNRs. In this paper, we design a novel coding scheme to produce sequences whose PSNRs are the combinations of different levels of PSNRs of YCbCr, with which the correlation between the subjective score and the combined PSNR is analyzed. Experiment results and statistical analysis demonstrate that the proposed CSPSNR correlates better with the mean opinion score than the existing methods.