Past work in motion-compensated interframe coding has been restricted to two-dimensional translation. It is the purpose of this paper to report some experimental results of a study on the potential advantage of considering more general types of motion. More specifically, we shall consider general two-dimensional motion including translation, rotation, and scale change (zooming). The entropy of the histogram of motion-compensated frame differences will be used as a performance measure. For comparison, this quantity will be measured for the case of using only two-dimensional translation as well as the case of using general two-dimensional motion.