ImageGear for C and C++ on Windows v21.0 - Updated
API Reference Guide / Core Component API Reference / Core Component Functions Reference / Display Functions / IG_dspl_LUT_set
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    IG_dspl_LUT_set
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    This function assigns new values to red, green, and blue look-up tables.

    Declaration:

     
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    AT_ERRCOUNT  ACCUAPI  IG_dspl_LUT_set(
            [IN] HIGEAR hIGear,
            [IN] DWORD dwGrpID,
            [IN] AT_MODE nFlags,
            [IN] const LPBYTE lpRLUT,
            [IN] const LPBYTE lpGLUT,
            [IN] const LPBYTE lpBLUT
    );
    

    Arguments:

    Name Type Description
    hIGear HIGEAR ImageGear handle of image.
    dwGrpID DWORD Identifier of group in which to set LUT options.
    nFlags AT_MODE Specify which look-up tables to set. Possible value is 0 or a combination of flags IG_DSPL_R_CHANNEL - if this flag is set then the lpRLUT parameter of this function is not ignored IG_DSPL_G_CHANNEL - if this flag is set then the lpGLUT parameter of this function is not ignored IG_DSPL_B_CHANNEL - if this flag is set then the lpBLUT parameter of this function is not ignored The constant IG_DSPL_ALL_CHANNELS is defined for convenience and can be used to set all three channels.
     
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    #define IG_DSPL_ALL_CHANNELS
    (IG_DSPL_R_CHANNEL|IG_DSPL_G_CHANNEL|IG_
    DSPL_B_CHANNEL)
    
    lpRLUT const LPBYTE Pointer to a 256 element array of a red look-up table to set. If NULL, then identity the array is assigned to RedLut option.
    lpGLUT const LPBYTE Pointer to a 256 element array of a green look-up table to set. If NULL, then identity the array is assigned to GreenLut option.
    lpBLUT const LPBYTE Pointer to a 256 element array of a blue look-up table to set. If NULL, then identity the array is assigned to BlueLut option.

    Return Value:

    Returns the number of ImageGear errors that occurred during this function call.

    Supported Raster Image Formats:

    All pixel formats supported by ImageGear for C and C++.

    Sample:

    None

    Example:

     
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    HIGEAR    hIGear;         /* HIGEAR handle of image  */ 
    DWORD    nGrpID;        /* display group identifier  */
    BYTE     lut[256];      /* lookup array  */
    INT      i;
     ...
    /* set inverted look-up table */
    for( i = 0; i<256; i++ )
            lut[i] = 255 - i;
    IG_dspl_LUT_set( hIGear, nGrpID, IG_DSPL_ALL_CHANNELS, lut, lut, lut );
    

    Remarks:

    ImageGear always makes a copy of lpRLUT, lpGLUT and lpBLUT in case they are needed, but does not assign pointers directly so that the application should cleanup the memory allocated for them.