US Patent 7376186 Motion estimation with weighting prediction

A video encoder and decoder are provided for encoding and decoding video signal data for an image block and a particular reference picture index to predict the image block, where the encoder includes a reference picture weighting factor selector having an output indicative of a weighting factor corresponding to the particular reference picture index, a multiplier in signal communication with the reference picture weighting factor selector for providing a weighted version of the reference picture, and a motion estimator in signal communication with the multiplier for providing motion vectors corresponding to the weighted version of the reference picture; and the corresponding decoder a reference picture weighting factor unit having an output for determining a weighting factor corresponding to the particular reference picture index.