A background memory update scheme for H.263 video codec

In the majority of video conference applications, the camera position and its focus are fixed and the scene in the picture is stationary. When the subject moves, some occluded background reappears in the scene. Such uncovered background part usually has to be spatially encoded. In this paper, we propose a background memory update scheme for H.263 video codec which can use the previously transmitted background scene as the reference so that a higher coding efficiency can be achieved. The proposed method only uses available information in the macroblock level to update the background memory. Thus the extra computational load is small and the synchronisation of the background memory is easy to achieve. The experimental results show that the proposed scheme gives improved performance both in terms of objective and subjective criteria.