System and Method for Fast Variable-Size Motion Estimation

Abstract

Methods and systems for fast variable block-size motion estimation based on merging and splitting procedures for AVC video encoding are disclosed. The methods take advantage of the correlation of the Motion Vectors (MVs) of the different block-size modes to achieve a good computation reduction. Considering that the smaller the block-size difference between two block-sizes is, the more correlations between their MVs can be expected, the methods use a 8*8 block as an initial processing block to calculate prediction MVs. The prediction MVs are then used in predicting MVs for other block-sizes.

1 . A system module for fast motion estimation of variable block sizes of a video image frame, comprising:
 a first motion estimation sub-module for processing an initial n×m block to obtain a plurality of prediction MVs; and   a merging sub-module for merging the n×m block into larger-size blocks and for receiving the plurality of prediction MVs from the first motion estimation sub-module, the merging sub-module using the plurality of prediction MVs to calculate prediction MVs for the larger-size blocks.   
   
   
       2 . The system of  claim 1 , further comprising a splitting sub-module for splitting the n×m block into smaller-size blocks and for receiving the plurality of prediction MVs from the first motion estimation sub-module, the splitting sub-module using the plurality of prediction MVs to calculate prediction MVs for the smaller-size blocks. 
   
   
       3 . The system module of  claim 1 , further comprising at least one memory that provides a reference image frame and a current image frame to the first motion estimation sub-module for processing. 
   
   
       4 . The system module of  claim 1 , further comprising a minimum cost measurement sub-module, the minimum cost measurement sub-module receiving the prediction MVs for the larger-size blocks, calculating a smallest Lagrangian cost from the prediction MVs, and determining a preferred Block Mode and corresponding MVs. 
   
   
       5 . The system module of  claim 1 , wherein the merging sub-module utilizes an Adaptive Diversity Search Strategy (ADSS) to calculate the prediction MVs for the larger-size blocks. 
   
   
       6 . The system module of  claim 2 , wherein the splitting sub-module utilizes an Adaptive Diversity Search Strategy (ADSS) to calculate the prediction MVs for the smaller-size blocks. 
   
   
       7 . The system module of  claim 1 , wherein n=8, and m=8. 
   
   
       8 . The system module of  claim 1 , wherein the merging sub-module does not function when n=16, and m=16. 
   
   
       9 . The system module of  claim 2 , wherein the splitting sub-module does not function when n=4 and m=4. 
   
   
       10 . The system of  claim 1 , further comprising a sub-module for conducting a MV search with Small Diamond Search Pattern (SDSP) on the prediction MVs obtained by the merging sub-module. 
   
   
       11 . A system module for fast motion estimation of variable block sizes of a video image frame, comprising:
 a first motion estimation sub-module for processing an initial n×m block to obtain a plurality of prediction MVs; and   a splitting sub-module for splitting the n×m block into smaller-size blocks and for receiving the plurality of prediction MVs from the first motion estimation sub-module, the splitting sub-module using the plurality of prediction MVs to calculate prediction MVs for the smaller-size blocks.   
   
   
       12 . The system of  claim 11 , further comprising a merging sub-module for merging the n×m block into larger-size blocks and for receiving the plurality of prediction MVs from the first motion estimation sub-module, the merging sub-module using the plurality of prediction MVs to calculate prediction MVs for the larger-size blocks. 
   
   
       13 . The system module of  claim 11 , further comprising at least one memory that provides a reference image frame and a current image frame to the first motion estimation sub-module for processing. 
   
   
       14 . The system module of  claim 11 , further comprising a minimum cost measurement sub-module, the minimum cost measurement sub-module receiving the prediction MVs for the smaller-size blocks, calculating a smallest Lagrangian cost from the prediction MVs, and determining a preferred Block Mode and corresponding Mvs. 
   
   
       15 . The system module of  claim 11 , wherein the splitting sub-module utilizes an Adaptive Diversity Search Strategy (ADSS) to calculate the prediction MVs for the smaller-size blocks. 
   
   
       16 . The system module of  claim 12 , wherein the merging sub-module utilizes an Adaptive Diversity Search Strategy (ADSS) to calculate the prediction MVs for the larger-size blocks. 
   
   
       17 . The system module of  claim 11 , wherein n=8, and m=8. 
   
   
       18 . The system of  claim 11 , further comprising a sub-module for conducting a MV search with Small Diamond Search Pattern (SDSP) on the prediction MVs obtained by the splitting sub-module.