ImageGear TWAIN Component provides the following callback functions:
- LPFNIG_TWAIN_AFTER_AUDIO_SNIPPET
- LPFNIG_TWAIN_AFTER_DOC
- LPFNIG_TWAIN_AFTER_PAGE
- LPFNIG_TWAIN_AFTER_TRANSFORM_PAGE
- LPFNIG_TWAIN_BEFORE_DOC
- LPFNIG_TWAIN_BEFORE_PAGE
- LPFNIG_TWAIN_CAP_SET_5
- LPFNIG_TWAIN_DEVICE_EVENT