Method for Determining Boundary Strength

Abstract

A method for determining the boundary strengths of edges in a block-based digitally encoded image is disclosed. The method includes setting the boundary strength of two adjacent blocks in an Inter macroblock to a first strength value if any one of the two adjacent blocks contains non-zero prediction residual in the encoding data and setting the boundary strength thereof to a second strength value if the two adjacent blocks are located in the same motion compensation block. An edge with boundary strength equal to the second strength value will be skipped in a deblocking process.

1 . A method for determining boundary strengths of edges in a block-based digitally encoded image, the method comprising the steps of:
 if encoding data of any one of two adjacent blocks has non-zero prediction residual, then setting boundary strength of the two adjacent blocks to a first strength value; and   if the two adjacent blocks lie in the same motion compensation block, then setting the boundary strength of the two adjacent blocks to a second strength value,   wherein the two adjacent blocks are located in the same macroblock of the block-based digitally encoded image, and the macroblock is encoded in Inter Prediction mode, and a deblocking process for the block-based digitally encoded image applies deblocking operations with different strengths to edges with different boundary strength values.   
     
     
         2 . The method of  claim 1 , wherein the deblocking process skips any deblocking operation for any edge with boundary strength equal to the second strength value. 
     
     
         3 . The method of  claim 1 , wherein determining whether the two adjacent blocks lie in the same motion compensation block is performed through examining if the two adjacent blocks are located in the same partition or sub-partition of the macroblock. 
     
     
         4 . The method of  claim 3 , wherein the block is a 4×4 pixel area, and wherein the partition is a pixel area with size of 16×16, 16×8, 8×16 or 8×8 pixels. 
     
     
         5 . The method of  claim 3 , wherein the block is a 4×4 pixel area, and wherein the sub-partition is a pixel area with size of 8×8, 8×4 or 4×8 pixel. 
     
     
         6 . The method  claim 2 , further comprising:
 if the two adjacent blocks lie in different motion compensation blocks and have different numbers of motion vectors, then setting the boundary strength of the two adjacent blocks to a third strength value.   
     
     
         7 . The method of  claim 6 , wherein the strength of the deblocking operation applied to an edge with boundary strength equal to the first strength value is stronger than the strength of the deblocking operation applied to an edge with boundary strength equal to the third strength value.