Built-in Conversion

The Color Conversion C++ Class Library provides built-in conversion. To do a built-in conversion, follow the steps below:

1. Define the following global variables:

   LColor clr; 
   CONVERSION_PARAMS params; 
   WHITEPOINT WPoint; 
   L_UCHAR *pRGBData; 
   L_UCHAR *pLABData; 
   L_INT nWidth; 
   L_INT nHeight; 
   L_INT nInAlign; 
   L_INT nOutAlign; 

2. Set the conversion options by filling a CONVERSION_PARAMS structure:

   ZeroMemory(&params, sizeof(CONVERSION_PARAMS)); 
   params.pWpoint = &WPoint; 
   params.uStructSize = sizeof(CONVERSION_PARAMS); 
   params.pWpoint->nWhitePoint = CIELAB_D50; 
   params.nQuantization = 8; 
   params.nMethod = USE_BUILTIN; 
   params.nActiveMethod = USE_BUILTIN; 
   params.pWpoint->xWhite = 0.0; 
   params.pWpoint->yWhite = 0.0; 

3. Initialize the color conversion object with LColor::Initialize():

   clr.Initialize (CCS_RGB, CCS_LAB, &params); 

4. Convert from RGB to CIELab:

   clr.Convert (pRGBData, pLABData, nWidth, nHeight, nInAlign, nOutAlign); 

5. At the end, free the color conversion object:

   clr.Free();