ImageGear for C and C++ on Linux v19.10 - Updated
IG_fltr_metad_callback_get
API Reference Guide > Core Component API Reference > Core Component Functions Reference > Filter Functions > IG_fltr_metad_callback_get

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.

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.