Limited motion estimation scheme for multimedia video compression

This paper presents a computationally efficient motion estimation technique based on image sampling which determines the dominant motion between pairs of images. The technique is suited to low complexity, low bit rate multimedia applications, where the objective is to achieve good fidelity without the overhead of full motion compensation. This can be achieved if the dominant motion is a combination of translation, rotation and zoom, which can be described by a similarity transformation. The method adopts a new approach to determining the model parameters, based on generating a list of parameter estimates from pairs of block motion vectors and selecting the mean of those estimates close to the median, The method gives a good sub-pixel dominant motion estimate by sampling as little as 1/20^th of the image area. Results show the method to be accurate and robust, with low computational requirements