Method and apparatus for encoding/decoding image information

Abstract

The present invention relates to a deblocking filtering method, a method for inducing bs (boundary strength) therefor, and a method and an apparatus for encoding/decoding using the same. The method for inducing the bS of the present invention comprises the steps of: inducing a boundary of a deblocking filtering unit block as a unit block for applying the deblocking filtering; and setting the bS according to each bS setting unit block within the deblocking filtering unit block, wherein the bS setting step can set a bS value for a target boundary corresponding to a boundary of the deblocking filtering unit block as the bs setting unit block.

1 . (canceled) 
     
     
         2 . A deblocking filtering method, performed by an encoding apparatus, the method comprising:
 deriving a boundary of a deblocking filtering unit block in a reconstructed picture, wherein the deblocking filtering unit block is a unit block on which deblocking filtering is performed;   setting a boundary strength (bS) of a target boundary in the boundary of the deblocking filtering unit block; and   applying deblocking filtering on the boundary of the deblocking filtering unit block using two bSs for the target boundarys in the boundary of the deblocking filtering unit block,   wherein the applying deblocking filtering includes:   determining, based on predetermined sample row or sample column accrossing the target boundary, whether the deblocking filtering is to be applied when the bS value set for the target boundary is larger than 0;   determining whether strong filtering or weak filtering is applied when it is determined that the deblocking filtering is to be applied; and   filtering samples neighboring the boundary of the deblocking filtering unit block based on the determined strong filtering or weak filtering,   wherein the deblocking filtering unit block corresponds to a transform block, a prediction block or an 8×8 pixel block,   wherein a length of the target boundary to which the bS is set is 4 pixel, and   wherein the deblocking filtering unit block corresponds to the 8×8 pixel block when the transform block and the prediction block are smaller than the 8×8 pixel block.   
     
     
         3 . The deblocking filtering method according to  claim 2 , wherein the setting the bS includes setting the bS value of the target boundary to 2 in a case that at least one of two blocks facing the target boundary as a boundary is intra-coded; setting the bS value of the target boundary to 1 in a case that the target boundary is a deblocking filtering target and not in the case that at least one of two blocks with the target boundary as a boundary is intra-coded; and setting the bS value of the target boundary to 0 in a case that the target boundary is not a deblocking filtering target. 
     
     
         4 . The deblocking filtering method according to  claim 3 , wherein the case in which the bS is set to 1 is not the case in which at least one of two blocks with the target boundary as a boundary is intra-coded and includes:
 a case in which at least one of the at least one of two blocks with the target boundary as a boundary includes a transform coefficient other than 0; and   a case in which the two blocks with the target boundary as a boundary have different reference pictures or different motion vectors.   
     
     
         5 . The deblocking filtering method according to  claim 2 ,
 wherein whether the deblocking filtering is to be applied is determined based on the predetermined sample row when the target boundary is a vertical edge,   wherein whether the deblocking filtering is to be applied is determined based on the predetermined sample column when the target boundary is a horizontal edge.   
     
     
         6 . The deblocking filtering method according to  claim 2 , wherein the bS is one of 3 case values, the 3 case values includes 0, 1 and 2. 
     
     
         7 . A non-transitory decoder-readable storage medium storing a bitstream generated by a method, the method comprising:
 deriving a boundary of a deblocking filtering unit block in a reconstructed picture, wherein the deblocking filtering unit block is a unit block on which deblocking filtering is performed;   setting a boundary strength (bS) of a target boundary in the boundary of the deblocking filtering unit block;   applying deblocking filtering on the boundary of the deblocking filtering unit block using two bSs for the target boundarys in the boundary of the deblocking filtering unit block, and   encoding image information including information on the deblocking filtering to generate the bitstream,   wherein the applying deblocking filtering includes:   determining, based on predetermined sample row or sample column accrossing the target boundary, whether the deblocking filtering is to be applied when the bS value set for the target boundary is larger than 0;   determining whether strong filtering or weak filtering is applied when it is determined that the deblocking filtering is to be applied; and   filtering samples neighboring the boundary of the deblocking filtering unit block based on the determined strong filtering or weak filtering,   wherein the deblocking filtering unit block corresponds to a transform block, a prediction block or an 8×8 pixel block,   wherein a length of the target boundary to which the bS is set is 4 pixel, and   wherein the deblocking filtering unit block corresponds to the 8×8 pixel block when the transform block and the prediction block are smaller than the 8×8 pixel block.