Motion compensation technique for down-scaled pictures in layered coding

This paper propeses a new motion compensation (MC) technique which reduces blurring called drift in moving pictures down-scaled with layered coding system. Encoder of the system compresses large amounts of digital video data in the same way of MPEG (Moving Picture Experts Group) algorithm. Decoder, on the other hand, expands a part of the compressed data and reconstructs down scaled pictures. The purpose of this paper is to reduce blurring which is observed in the reconstructed pictures. In this paper, cause of the blurring is analyzed and the method is introduced as a solution to the problem. The new method is implemented by a little modification of motion compensation (MC) of the decoder, namely increasing the number of tap of interpolation filters of the MC. Compressing moving pictures, its effectiveness is also confirmed by means of not only subjective test but also signal to noise ratio.