Derivation process of boundary filtering strength, and deblocking filtering method and apparatus using the derivation process

Abstract

Provided are a bS derivation process and a deblocking filtering method and apparatus using illumination compensation and/or chrominance compensation, such as a multi-view video coding, in a picture coding/decoding process in which a prediction coding is performed. If neither of the two blocks are intra-coded, neither of the two blocks do contain a none-zero transformed coefficient, and motion compensation for the two blocks is performed based on the identical reference frame and the absolute difference between the horizontal or vertical components of the two motion vectors of the two blocks is less than 1, the bS of the two blocks is derived by considering whether the two blocks are coded by illumination compensation (IC) according to an embodiment of the present invention. Specifically, if both of the two blocks are coded by IC mode or neither of the two blocks are coded by IC mode, bS is set as such a value that filtering is unnecessary. On the other hand, if both of the two blocks are coded by IC mode and the blocks have different illumination change values, or only one of the blocks is coded by IC mode, the bS is derived using difference of illumination change values or the illumination change value.

What is claimed is: 
     
         1 . A boundary filtering strength (bS) derivation method for deblocking filtering, the method comprising:
 determining by a deblocking filtering apparatus whether at least one of two neighboring blocks is intra-coded;   determining by the deblocking filtering apparatus whether the two neighboring blocks are transform blocks and at least one of the two neighboring blocks contains a transform coefficient, or whether the two neighboring blocks are inter-coded and motion information for one block is different from motion information for the other block; and   determining by the deblocking filtering apparatus whether the two neighboring blocks are coded by illumination compensation (IC) mode,   wherein each of the step is performed when the result of the determination in the previous step is negative.   
     
     
         2 . The method of  claim 1 , wherein for the two neighboring blocks, the motion information for one block is different from the motion information for the other block when a reference picture of one block is different from a reference picture of the other block, or an absolute difference between horizontal or vertical component of a motion vector for one block and horizontal or vertical component of a motion vector for the other block is greater than or equal to an integer sample. 
     
     
         3 . The method of  claim 1 , the step of determining whether the two neighboring blocks are transform blocks and at least one of the two neighboring blocks contains a transform coefficient, or whether the two neighboring blocks are inter-coded and motion information for one block is different from motion information for the other block, is performed when neither of the two neighboring blocks are intra-coded. 
     
     
         4 . The method of  claim 1 , the step of determining whether the two blocks are coded by IC mode is performed when neither of the two neighboring blocks are intra-coded, at least one of the two neighboring blocks is not a transform block or neither of the two neighboring blocks contains a transform coefficient, or the motion information for one block is different from the motion information for the other block. 
     
     
         5 . The method of  claim 1 , wherein the determining whether the two neighboring blocks are coded by IC mode comprises determining whether both of the two neighboring blocks are coded by IC mode and the two neighboring blocks have different illumination change values, or only one of the two blocks is coded by illumination compensation mode. 
     
     
         6 . The method of  claim 5 , wherein if both of the two neighboring blocks are coded by IC mode and the two neighboring blocks have different illumination change values, the bS is derived using a difference between the illumination change values of the two blocks; and
 if only one of the two neighboring blocks is coded by IC mode, the bS is derived using the illumination change value of the block coded by IC mode.   
     
     
         7 . The method of  claim 6 , wherein when the difference between the illumination change values or the illumination change value of the block coded by IC mode is equal to or greater than a predetermined threshold value, bS is set as a bS of a first value, on the other hand, when the difference between the illumination change values or the illumination change value of the block coded by IC mode is less than the threshold value, bS is set as a bS of a second value. 
     
     
         8 . A method of deblocking filtering, the method comprising:
 deriving a bS by a deblocking filtering apparatus for neighboring two blocks; and   applying deblocking filtering by the deblocking filtering apparatus with respect to pixel values of the two neighboring blocks according to the bS,   wherein the deriving bS comprises:   determining by a deblocking filtering apparatus whether at least one of two neighboring blocks is intra-coded;   determining by the deblocking filtering apparatus whether the two neighboring blocks are transform blocks and at least one of the two neighboring blocks contains a transform coefficient, or whether the two neighboring blocks are inter-coded and motion information for one block is different from motion information for the other block; and determining by the deblocking filtering apparatus whether the two neighboring blocks are coded by illumination compensation (IC) mode,   wherein each of the step is performed when the result of the determination in the previous step is negative.   
     
     
         9 . The method of  claim 8 , wherein for the two neighboring blocks, the motion information for one block is different from the motion information for the other block when a reference picture of one block is different from a reference picture of the other block, or an absolute difference between horizontal or vertical component of a motion vector for one block and horizontal or vertical component of a motion vector for the other block is greater than or equal to an integer sample. 
     
     
         10 . The method of  claim 8 , the step of determining whether the two neighboring blocks are transform blocks and at least one of the two neighboring blocks contains a transform coefficient, or whether the two neighboring blocks are inter-coded and motion information for one block is different from motion information for the other block, is performed when neither of the two neighboring blocks are intra-coded. 
     
     
         11 . The method of  claim 8 , the step of determining whether the two blocks are coded by IC mode is performed when neither of the two neighboring blocks are intra-coded, at least one of the two neighboring blocks is not a transform block or neither of the two neighboring blocks contains a transform coefficient, or the motion information for one block is different from the motion information for the other block. 
     
     
         12 . The method of  claim 8 , wherein the determining whether the two neighboring blocks are coded by IC mode comprises determining whether both of the two neighboring blocks are coded by IC mode and the two neighboring blocks have different illumination change values, or only one of the two blocks is coded by illumination compensation mode. 
     
     
         13 . The method of  claim 12 , wherein if both of the two neighboring blocks are coded by IC mode and the two neighboring blocks have different illumination change values, the bS is derived using a difference between the illumination change values of the two blocks; and
 if only one of the two neighboring blocks is coded by IC mode, the bS is derived using the illumination change value of the block coded by IC mode.   
     
     
         14 . The method of  claim 13 , wherein when the difference between the illumination change values or the illumination change value of the block coded by IC mode is equal to or greater than a predetermined threshold value, bS is set as a bS of a first value, on the other hand, when the difference between the illumination change values or the illumination change value of the block coded by IC mode is less than the threshold value, bS is set as a bS of a second value.