Dual frame motion compensation with uneven quality assignment

Video codecs that use motion compensation have shown PSNR gains from the use of multiple frame prediction, in which more than one past reference frame is available for motion estimation. In dual frame motion compensation, one short-term reference frame and one long-term reference frame are available for prediction. In this paper, we propose a dual frame motion compensation technique that allocates bits unevenly among frames to periodically create a high-quality frame that serves as the long-term reference frame for some time. By modifying an MPEG-4 encoder to use this technique on a set of video sequences, we show that it outperforms a normal dual frame motion compensation scheme in which the long-term reference frames are regular frames that are not allocated any extra rate.