From Tracker Software PDF SDK
IPXV_FormatConverter interface is a base for two other interfaces - IPXV_ImportConverter and IPXV_ExportConverter - that are used to have an ability to open from and save to files other than PDF. All converters should be registered using methods IPXV_Inst::RegisterImportConverter and IPXV_Inst::RegisterExportConverter.
This interface defines common properties and methods for both Import and Export converters. Parameters are restored by the Editor before use and stored automatically when they were changed in Editor's UI (Open/Save dialog, Preferences).