抄録
Experiments have shown that the bi-directional prediction, which is the heart of MPEG-2, plays a very important role in its coding efficiency. Theoretical analysis shows, however, that the efficiency is degraded, if the auto-correlation similar to the spatial correlation, ρ_n=ρ^n (denotedρ_n=ρ**n, hereafter) is assumed. The contradiction can be made clear, if the temporal correlation is assumed asρ_n=ρ**(√^ r<n>), as Dr. Katto proposed. In this presentation, the temporal correlation with motion-compensation is measured, and the coding efficiency is discussed based on this.
