Patent ID: 11924477
Assignee: DOLBY LABORATORIES LICENSING CORPORATION
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H  G | IPC H

Claim 0:
1. A non-transitory computer-readable medium storing instructions for performing with a processor a method for color conversion, the method comprising:
receiving an input picture in a linear RGB color space;
generating a first picture in an LMS color space by applying an RGB to LMS color transformation to the input picture, wherein the RGB to LMS transformation comprises, (
    
     
      
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       M
      
     
     
      
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    )
   
   =
   
    
     
      (
      
       
        
         
          1
          ⁢
          6
          ⁢
          8
          ⁢
          8
         
        
        
         
          2
          ⁢
          1
          ⁢
          4
          ⁢
          6
         
        
        
         
          2
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          6
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          2
         
        
       
       
        
         
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          8
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          9
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          9
         
        
        
         
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          9
         
        
        
         
          3
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          6
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          8
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      )
     
     /
     4
    
    ⁢
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    9
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    6
    *
    
     (
     
      
       
        R
       
      
      
       
        G
       
      
      
       
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     )
    
   
  
  ;
 

applying a non-linear function to each color component of the first picture to generate color components of a second picture in a non-linear LMS color space, wherein the non-linear function comprises one of: an inverse of an SMPTE ST 2084 electro-optical transfer function or a Hybrid Log-Gamma (HLG) function; and
generating an output picture in an ICtCp color space by applying a color transformation matrix to the color components of the second picture, wherein the color transformation matrix comprises:, [
   
    
     
      
       2
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       4
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      0
     
    
    
     
      
       6
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        -
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       7
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   ]
  
  /
  4096.