A new motion-compensated transform coding scheme

Motion-compensated coding schemes are based on estimation of moving objects within a scene. The success of a motion-compensation scheme highly depends on the ability to estimate the displacement correctly. Also the construction of the displaced block is important. The aim of these schemes is to minimize the prediction error in order to quantize it with fewer bits. Displacement estimation is usually performed in the pixel domain, where the compensation is carried out either in the pixel or in the transform domain. We describe a transform domain oriented estimation and compensation method where the displacement of the transformed sub-block is calculated in an efficient way by use of a displacement matrix. The method is based on a two-dimensional block by block coefficient technique. The properties of the transform displacement matrix (nilpotent operator) are explained.