Edge degradation for objective video quality metrics

Abstract

In this paper, we propose a new method for an objective measurement of video quality based on edge degradation. One of the most important requirements for an objective method for video quality measurement is that it should provide consistent performances over a wide range of video sequences that are not used in the designing stage. By analyzing subjective scores of various video sequences, we found that the human visual system is sensitive to degradation around edges. In other words, when edge areas of a video are blurred, evaluators tend to give low scores to the video even though the overall mean squared error is not so large. Based on this observation, we propose an objective video quality measurement method that measures degradation around edges. In the proposed method, we first apply an edge detection algorithm to videos and find edge areas. Then, we measure degradation of those edge areas by computing mean squared error. From this mean squared error, we compute the PSNR and use it as video quality metric. Experimental results show that the proposed method compares favorably with the current objective methods for video quality measurement. Furthermore, when the proposed method is applied to test video sequences that are not used in the designing stage, it still consistently provides satisfactory performances.