Patent ID: 8116375
Filing Date: 2012-02-14
Classification: H04N

Abstract:
1. A method for obtaining an image reference block in a picture in a code mode of fixed reference frame number in image encoding/decoding of digital video, comprising the steps of: (a) performing motion estimation for each block of a current B frame and obtaining a motion vector MV of a corresponding block of a backward reference frame; (b) discriminating whether a reference frame corresponding to the motion vector is beyond a maximum forward reference frame which is pointed by the B frame, if not, proceeding to step (c); else, proceeding to step (d); (c) a forward motion vector and a backward motion vector of a macro block being able to be calculated by the following formulas: assuming MV here, tb is a distance in time domain between a current picture and a forward reference picture, and td is a distance in time domain between a forward reference picture and a backward reference picture; (d) a forward motion vector and a backward motion vector of the macro block being able to be calculated by the following formulas: assuming MV here, tb is a distance in time domain between a current picture and a forward reference picture, td is a distance in time domain between a forward reference picture and a backward reference picture, and tb′ is a distance in time domain between the current B frame and the forward reference frame which is pointed by the B frame; (e) two image blocks pointed by the MV