LPAFT_IG_METAD_ITEM_SET

If this callback function is defined in the format filter then during filter WRITE operation it is called every time when some data is ready to be written.

Declaration:

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typedef AT_BOOL (LPACCUAPI LPAFT_IG_METAD_ITEM_SET_CB)( LPVOID lpPrivate, AT_MODE FormatID, LPCHAR ItemName, DWORD ItemID, AT_MODE ItemType, LPVOID ItemValue, AT_MODE ValueType, DWORD ValueLength, AT_BOOL ReadOnlyValue, LPVOID NewItemValue, LPAT_MODE NewValueType, LPDWORD *NewValueLength );

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typedef AT_BOOL (LPACCUAPI LPAFT_IG_METAD_ITEM_SET_CB)(
        LPVOID lpPrivate, 
        AT_MODE FormatID, 
        LPCHAR ItemName,  
        DWORD ItemID, 
        AT_MODE ItemType, 
        LPVOID ItemValue, 
        AT_MODE ValueType,
        DWORD ValueLength,
        AT_BOOL ReadOnlyValue, 
        LPVOID *NewItemValue,
        LPAT_MODE *NewValueType,
        LPDWORD *NewValueLength
);

Arguments:

lpPrivate	Private callback data associated with metadata callback function.
FormatID	The ID of format filter that send or get the item (IG_FORMAT_... constant).
ItemName	Text name of item.
ItemID	Numerical ID of item.
ItemType	Specifies the type of item and reflect the status of given record. Possible values are: IG_METAD_VALUE_ITEM - this value specifies that current item is value of simplest type and field Value contains actual value of item and ValueType contains identifier of type of this item. ReadOnly can be either TRUE (readonly ) or FALSE (read/ write). Name and/or Id contains textual and numerical identification of item. IG_METAD_LEVEL_START - this value specifies that current item opens sublevel of items and all next items up to correspondent item with LEVEL_END value belongs to this sublevel. IG_METAD_LEVEL_END - this value close current sublevel and tells that next item belongs to higher level.
ItemValue	If ItemType = IG_METAD_VALUE_ITEM then this argument contains actual value of item of type specified by ValueType parameter.Value is stored as array of elements where each element contains values of type ValueType. Length of array is provided in parameter ValueLength.
ValueType	If ItemType = IG_METAD_VALUE_ITEM then ValueType contains actual type of value stored in ItemValue pointer. See Non-Image data format section for the exact list of possible types.
ValueLength	If ItemType = IG_METAD_VALUE_ITEM then VaueLength contains number of elements in array ValueItem of type specified by ValueType.
ReadOnlyValue	If this argument is TRUE then actual value of item can not be changed by callback function and value is passed for information purpose only. If FALSE then value of item can be changed and application can provide new value through next three parameters.
NewItemValue	Pointer to new item value that application may request to set as replacement of data passed in ItemValue parameter. If it is not NULL then next two parameters contain the type of value and length of array of elements.
NewValueType	Specifies the type of new item value passed through NewItemValue parameter.
NewValueLength	Specifies the size of array passed through NewItemValue pointer.

Return Value:

Returns TRUE if ImageGear should overwrite the default item data with your data, or FALSE if ImageGear should ignore your data.

Supported Raster Image Formats:

This function does not process image pixels.

Sample:

JPEG

Example:

See example for IG_fltr_metad_callback_set() function.

Remarks:

Application can change/provide new value for given item using NewItemValue, NewValueType and NewValueLength parameters. This new value is to be used as replacement for default data passed through ItemValue parameter in the case if ReadOnlyValue is FALSE. Callback function should return TRUE if callback function has changed value, and FALSE if it is not changed.

ImageGear Professional DLL v17.1 for Windows
LPAFT_IG_METAD_ITEM_SET_CB
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