摘要 |
A video coding method for deriving motion vectors for a bi-predictive block in direct mode is disclosed, the method comprising: determining motion vectors of the bi-predictive block; and decoding the bi-predictive block based on the determined motion vectors. The method further comprises determining a kind of a reference picture pointed to by a motion vector of a co-located block, the kind of the reference picture including a long-term reference picture and a short-term reference picture. In determining motion vectors of the bi-predictive block a backward motion vector of the bi-predictive block is set equal to zero, if the kind of the reference picture is the long-term reference picture. |