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    1 {-# language CPP #-}
    2 
    3 #ifndef ENABLE_INTERNAL_DOCUMENTATION
    4 {-# OPTIONS_HADDOCK hide #-}
    5 #endif
    6 
    7 module OpenCV.Internal.Core.Types.Mat.Marshal
    8     ( marshalDepth
    9     , unmarshalDepth
   10     , marshalFlags
   11     , unmarshalFlags
   12     ) where
   13 
   14 import "base" Data.Bits
   15 import "base" Data.Int
   16 import "base" Data.Monoid ( (<>) )
   17 import "this" OpenCV.Internal.Core.Types.Mat.Depth
   18 
   19 --------------------------------------------------------------------------------
   20 
   21 #include <bindings.dsl.h>
   22 #include "opencv2/core.hpp"
   23 
   24 #include "namespace.hpp"
   25 
   26 --------------------------------------------------------------------------------
   27 
   28 #num CV_8U
   29 #num CV_8S
   30 #num CV_16U
   31 #num CV_16S
   32 #num CV_32S
   33 #num CV_32F
   34 #num CV_64F
   35 #num CV_USRTYPE1
   36 
   37 marshalDepth :: Depth -> Int32
   38 marshalDepth = \case
   39     Depth_8U       -> c'CV_8U
   40     Depth_8S       -> c'CV_8S
   41     Depth_16U      -> c'CV_16U
   42     Depth_16S      -> c'CV_16S
   43     Depth_32S      -> c'CV_32S
   44     Depth_32F      -> c'CV_32F
   45     Depth_64F      -> c'CV_64F
   46     Depth_USRTYPE1 -> c'CV_USRTYPE1
   47 
   48 unmarshalDepth :: Int32 -> Depth
   49 unmarshalDepth n
   50     | n == c'CV_8U       = Depth_8U
   51     | n == c'CV_8S       = Depth_8S
   52     | n == c'CV_16U      = Depth_16U
   53     | n == c'CV_16S      = Depth_16S
   54     | n == c'CV_32S      = Depth_32S
   55     | n == c'CV_32F      = Depth_32F
   56     | n == c'CV_64F      = Depth_64F
   57     | n == c'CV_USRTYPE1 = Depth_USRTYPE1
   58     | otherwise          = error $ "unknown depth " <> show n
   59 
   60 #num CV_CN_SHIFT
   61 
   62 marshalFlags
   63     :: Depth
   64     -> Int32 -- ^ Number of channels
   65     -> Int32
   66 marshalFlags depth cn =
   67     marshalDepth depth
   68       .|. ((cn - 1) `unsafeShiftL` c'CV_CN_SHIFT)
   69 
   70 #num CV_CN_MAX  
   71 #num CV_MAT_DEPTH_MASK
   72 
   73 unmarshalFlags :: Int32 -> (Depth, Int32)
   74 unmarshalFlags n =
   75     ( unmarshalDepth $ n .&. c'CV_MAT_DEPTH_MASK
   76     , 1 + ((n `unsafeShiftR` c'CV_CN_SHIFT) .&. (c'CV_CN_MAX - 1))
   77     )