Patent ID: 8630348

Claim:
A method of determining and using a motion vector of a current image block, the method performed by a moving picture coding system and comprising: determining, by the moving picture coding system, a first motion vector of a current image block based on a kind of reference buffer storing a reference picture referenced by a co-located image block, the kind being one of long term and short term, the kind characterizing a temporal distance of the reference picture for the co-located image block with respect to the bi-predictive block, the determining step determining the first motion vector according to a first set of expressions if the reference buffer storing the reference picture is the short term kind and the determining step determining the first motion vector according to a second set of expressions if the reference buffer storing the reference picture is the long term kind, the second set of expressions being different than the first set of expressions; and decoding, by the moving picture coding system, the current image block based on the determined first motion vector.