[gdal-dev] FITS driver update?

[Chiara Marmo]

Hi gdal-list,

I work in a planetary/geology/astronomy lab, and I'm interested in having standard and full implementation of FITS format in GDAL.
Geographical metadata are not yet well defined in FITS, then in the first time I'm just verifying that GDAL works as expected (by astronomers :) ) with FITS format.

I have forked the OsGeo project in https://github.com/epn-vespa/gdal/ and addressed three points:
1) FITS origin is defined on the left bottom corner of a raster, this is the expected behaviour of FITS processing software: I have modified the read and write block direction.
2) Unsigned INT 16 and 32 bit are supported by FITS via specific BZERO value (https://heasarc.gsfc.nasa.gov/docs/software/fitsio/c/c_user/node23.html): I have added USHORT and ULONG support.
3) BZERO BSCALE are 'reserved keywords' and copying them in the metadata produce inconsistency in reverse conversion: a FITS containing BZERO BSCALE is converted to tiff, tiff reconverted to FITS, BZERO BSCALE become strings and FITS visualization ended up in a 0 raster. I have excluded BZERO and BSCALE from metadata keywords.

I haven't figured out yet how to manage scaled values... this will take some more time, as geographical conversion.

I'm wondering if those small changes could be tested by the community and maybe integrated in the code at some time.

All comments are welcome!
Thanks for listening,
Chiara

-- 
Chiara Marmo
Ingénieur de Recherche GEOPS - Paris Sud-11
Bât 509
Tel: +33 (0)1 69 15 49 03