Calculation method for predicted motion vector

摘要

A method of predicting a motion vector of a current block in a bi-predictive picture to be decoded in direct mode, is disclosed, comprising: providing multiple reference pictures having a default indexing order by using a picture order count representing a display order of pictures; remapping the default index order using remapping information from an encoder; obtaining at least one motion vector of a block other than the current block, said other block referring to at least one reference picture indicated by a reference picture index for multiple reference pictures; comparing a picture order count value of the bi-predictive picture with a picture order count value of the at least one reference picture; and predicting the motion vector of the current block from the at least one motion vector of said other block, based on the comparison step.