抄録
In this paper, we will examine, through subjective assessment tests, the effectiveness of the bi-directional prediction scheme, which was adopted by MPEG as a standardized coding technique and which is generally assumed to be effective with respect to the coding efficiency. We will also clarify the distinctive picture quality degradation by way of the bi-directional prediction coding scheme, analyze causes, and evaluate the de7gradation quantitatively. Specifically, the assessment results show that the bi-directional prediction scheme works well in most of the sequences with respect to the picture quality improvement, but causes flickers to some sequences. The analyses show that for the picture with high contrast texture the resolution of the decoded image differs between the B-pictures and the P-pictures; this leads to the flicker through the gamma characteristics of a monitor. We will demonstrate that we can evaluate the flicker by simulating the electro-optic conversion process.
