A video encoding method includes extracting at least one reference macroblock from each of a plurality of reference frames to generate a plurality of reference macroblocks, computing a linear sum of the reference macroblocks using weighting factors to generate a predictive macroblock, generating a motion vector between the video macroblock and the reference macroblock corresponding to the predictive macroblock, generating a prediction error signal between the predictive macroblock and the video macroblock, and encoding the prediction error signal, a first index indicating the plurality of reference frames, a second index indicating the weighting factors and the motion vector.