more Erdas

[Anantha Prasad]

********Thank you to Wang Song for the list conversion options!!

One question that hasn't been fully addressed;  Does the ERDAS command cvt73
convert ver. 7.5 files to 7.3 format?  Entries to the list seem to indicate
it has been done, while colleagues at CSU have been unsuccessful in converting
7.5 to 7.3 using cvt73. A file is created, but it won't import to GRASS via
r.in.erdas.  The usefulness of ERDAS cvt73 wll determine the future
effectiveness of GRASS r.in.erdas. ************

>>
As far as I know Erdas7.5 uses the same format as 7.4. I have been able to convert 7.5 files using cvt73 to 7.3 and then use r.in.erdas without problems...HOwever there is one bug...r.in.erdas does not seem to import erdas file using map coordinates but uses screen coordinates - as a result the grass "region" is modified. You need to use r.support and edit the header file to bring it back to the original region, match the projection info and use g.region to verify the match. Also, in grass4.1beta there is i.in.erdas which brings in multiband erdas files directly from 7.4/7.5 format...but you still need to edit the header file in grass. Hope this helps.
Prasad. 217-244-2166 (prasad at ghat.inhs.uiuc.edu)