ImageGear for C and C++ on Windows v21.0 - Updated
API Reference Guide / Core Component API Reference / Core Component Functions Reference / Filter Functions / IG_fltr_metad_callback_get
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    IG_fltr_metad_callback_get
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    This function returns the callback functions that ImageGear uses to pass or receive metadata during save and load operations.

    Declaration:

     
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    AT_ERRCODE ACCUAPI IG_fltr_metad_callback_get(
       LPVOID* lpPrivate,
       LPAFT_IG_METAD_ITEM_SET_CB* lplpfnSetCB,
       LPAFT_IG_METAD_ITEM_ADD_CB* lplpfnAddCB,
       LPAFT_IG_METAD_ITEM_GET_CB* lplpfnGetCB
    );
    

    Arguments:

    Name Type Description
    lpPrivate LPVOID* Returns private data associated with metadata callback functions.
    lplpfnSetCB LPAFT_IG_METAD_ITEM_SET_CB* Returns pointer to callback function of type LPAFT_IG_METAD_ITEM_SET_CB that is used for Set metadata operation.
    lplpfnAddCB LPAFT_IG_METAD_ITEM_ADD_CB* Returns pointer to callback function of type LPAFT_IG_METAD_ITEM_ADD_CB that is used for Add metadata operation.
    lplpfnGetCB LPAFT_IG_METAD_ITEM_GET_CB* Returns pointer to callback function of type LPAFT_IG_METAD_ITEM_GET_CB that is used for Get metadata operation.

    Return Value:

    Returns 0 if successful. Otherwise, returns the number of ImageGear errors that occurred during this function call.

    Supported Raster Image Formats:

    This function does not process image pixels.

    Sample:

    See GUI component source code.

    Example:

     
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    AT_ERRCOUNT nErrcount;        // Count of returned errors on stack
    LPVOID lpPrivate;
    LPAFT_IG_METAD_ITEM_SET_CB lpfnSetCB;
    LPAFT_IG_METAD_ITEM_ADD_CB lpfnAddCB;
    LPAFT_IG_METAD_ITEM_GET_CB lpfnGetCB;
    
    // Get metadata callback functions
    nErrcount = IG_fltr_metad_callback_get(&lpPrivate, &lpfnSetCB, &lpfnAddCB, &lpfnGetCB);
    

    Remarks:

    A NULL value is valid for any parameter, if the corresponding information is not necessary to the application.

    See also IG_fltr_metad_callback_set, LPAFT_IG_METAD_ITEM_ADD_CB, LPAFT_IG_METAD_ITEM_GET_CB, LPAFT_IG_METAD_ITEM_SET_CB functions and the section Processing of non-image data through filter callback functions.