Lists all IPTC Record 7 (Pre-Object) DataSet tags.
Values:
| IGMDTAG_ID_IPTC_PREOBJ_SIZE_MODE | Size mode. |
| IGMDTAG_ID_IPTC_PREOBJ_MAX_SUBFILE_SIZE | Max subfile size. |
| IGMDTAG_ID_IPTC_PREOBJ_OBJ_DATA_SIZE_ANN | Object data size announced. |
| IGMDTAG_ID_IPTC_PREOBJ_MAX_OBJ_DATA_SIZE | Maximum object data size. |