ARSF Data Processing
ARSF Software: azgcorr and azexhdf
The ARSF distribute two proprietary programs (produced by Azimuth Sustems UK) for handling the post-flight processed ATM, CASI and navigation data. The software primarily operate on the HDF files supplied by the ARSF. The two distributed software are:
- azexhdf: a utility that provides general data extraction from the ARSF HDF data files. General data listings as well as application specific image data files can be created, eg: navigation, pixel view details, BIL, BIL-Envi, TIF and GeoTIFF, for data transfer to other packages.
- azgcorr: performs geocorrection (geolocation, geometrical rectification) of user data using the supplied aircraft navigation, creating a Level 3 product from Level 1 or Level 2 input data. Output images, with or without DEMs, on a variety of map projections, including British National Grid, overlay maps and vector data. User controls are provided for datum and map projection selection, pixel size, interpolation method, DEM (Digital Elevation Models) use, geoid-spheroid correction and fine tuning of registration on maps and vector data. Output files may also produced for use in atmospheric correction processing, eg MODTRAN and user Level 2 programs.
The software are freely distributed but only work on data supplied by the ARSF. Software may be obtained from the ARSF FTP site via a username and a password provided by ARSF~Processing. Alternatively, the latest version may be obtained by writing to Gary Llewellyn.
Software User Guide
A manual describing the use of both programs can be downloaded in .pdf format (213kb). Alterations recently made to the user guide include:
- Section 1 Future developments: updated
- Section 3.4 Digital Elevation models: the re-write includes a description of the use of multiple DEMs to allow the overlaying of a regional DEM with a detailed local one; this allows the composited DEM to be saved for further use
- Section 3.9 Geocorrection in the real world: this new section discusses the effects of radiometric calibration, atmospheric correction and use of DEMs to achieve optimum geocorrection (georeferencing) results
- Section 4.1 (Using azgcorr) Introduction: expands the description of the use of unix command line programs
- Section 4.4 System requirements: system requirements for using the Sun and Linux versions of the programs
- Section 4.5 Installing software: this new section covers typical software installation and problems that may be encountered
- Section 5.12 User controls for view vector adjustment: this new section describes the user controls for precise georeferencing
- Section 6 Program execution Options and Parameters: see options for Transverse Mercator Projection use ( -mTM and -mUTM ), View vector adjustment ( -u ) and DEM handling ( -e )
- Appendix B Map projections and parameters: this new section is filled with basic details of projection parameters as well as some references for further reading
- Appendix D AZSPS Level 1 and Level 3 HDF file details: describes items related to view vector adjustment