2025 Reduced Resolution Dataset GIS The ERDAS HFA format defines a heirachichal data structure used by many formats primarily associated with with the ERDAS Imagine software package for processing geospatial imagery. Other formats use this structure also, notably ArcGIS 'Reduced resolution datasets' and their auxilliary files. It may be possible to distinguish between distinct subsets of HFA with further research. Please contact the PRONOM team if you can assist with this. 234 National Library of Australia / National Library of Australia 20 Aug 2018 13 Mar 2023 fmt/1215 PUID img File extension ovr File extension rrd File extension aux File extension aoi File extension cff File extension fft File extension gcc File extension sig File extension sml File extension 1592 Reduced Resolution Dataset BOF: 'EHFA_HEADER_TAG', 0x00 1 Absolute from BOF 0 0 454846415F4845414445525F54414700