Method for predicting a bi-predictive block of a moving picture

Abstract

In the method for predicting a bi-predictive block of a moving picture, first and second distinct motion-compensated blocks are obtained using first and second motion vectors respectively. The bi-predictive block of the moving picture is predicted using first and second variable weight factors associated with the first and second distinct motion-compensated blocks, respectively.

What is claimed is: 
     
       1. A method for a decoding device moving picture coding system to predict a bi-predictive block of a current picture, the method comprising:
 deriving, by the decoding device, a first picture order count allocated to a first picture wherein the first picture is a reference picture of the current picture; 
 deriving, by the decoding device, a second picture order count allocated to the current picture; 
 deriving, by the decoding device, a third picture order count allocated to a second picture; 
 deriving, by the decoding device, a fourth picture order count allocated to a third picture, wherein the second picture is a reference picture of the third picture; 
 scaling, by the decoding device, a motion vector of a block in the third picture based on the first, second, third and fourth picture order counts to calculate obtain a first motion vector for the bi-predictive block; 
 determining, by the decoding device, a first motion-compensated block in the first picture by using the first motion vector; and  
 predicting, by the decoding device, the bi-predictive block by using the first motion-compensated block, respectively, 
 wherein the first picture order count, the second picture order count, the third picture order count, and the fourth picture order count are values counted in display order. 
 
     
     
       2. The method of claim 1, wherein the first picture is a closest reference picture of the current picture.