Patent ID: 11910011
Assignee: LG ELECTRONICS INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A non-transitory computer-readable storage medium storing a bitstream generated by a method, the method comprising:
deriving an intra prediction type for a current block as Multi Reference Line intra prediction (MRL), wherein the MRL is an intra prediction type based on an intra prediction reference line not adjacent to the current block;
constructing an intra prediction mode candidate list including a DC intra prediction mode based on intra prediction modes of neighboring blocks of the current block;
deriving an intra prediction mode of the current block based on the intra prediction mode candidate list;
generating a prediction sample of the current block based on the intra prediction type and the intra prediction mode;
encoding image information including prediction related information for the current block; and
generating the bitstream including the image information,
wherein based on the intra prediction mode of the current block being derived as the DC intra prediction mode, and a width of the current block being equal to a height of the current block, a DC value is derived based on an equation as follows:, deVal
  =
  
   
    (
    
     
      
       ∑
       
        
         x
         ′
        
        =
        0
       
       
        nTbW
        
         -
         1
        
       
      
      
       
        p
        [
        
         x
         ′
        
        ]
       
       [
       
        
         -
         1
        
        -
        refIdx
       
       ]
      
     
     +
     
      
       ∑
       
        
         y
         ′
        
        =
        0
       
       
        nTbH
        
         -
         1
        
       
      
      
       
        p
        [
        
         
          -
          1
         
         -
         refIdx
        
        ]
       
       [
       
        y
        ′
       
       ]
      
     
     +
     nTbW
    
    )
   
   ≫
   
    (
    
     
      Log
      ⁢
      2
      ⁢
      
       (
       nTbW
       )
      
     
     +
     1
    
    )
   
  
 

where dcVal represent the DC value and nTbW represent the width of the current block, and refIdx is a value of a reference line index for the intra prediction reference line, and the prediction sample is derived as the DC value.