The WIA item transfer format ID. For a list of available transfer formats, refer to WiaFileFormats.
The relevant System.Guid value for the file format Id.
Each WIA item's transfer format listed in the WiaFileFormats enumeration has a corresponding System.Guid value. To get that value, call the GetFormatGuid method, passing the format Id for the corresponding GUID value.
For an example, refer to WiaSession.EnumFormats.