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> Dear TGRASS Users,
> 
> In my current research thises I'm working on a project using GRASS. 
> My first problem is how to get a disk with GRASS 4.1 as soon as possible, can
> somebody help me to find that out and how much would that be? 
> The second problem I've got is how to get ERDAS data into GRASS.
> IWe want to import an 8-bit-LAN LANDSAT file into GRASS from ERDAS VGA 7.5.
> The file is about 70MB and in the BSQ-format. Unfortunatlely I was not able to
> import it yet. I've tried all the suggestions with BLK-Files[D[D[D[D[D[D[D[D[D[D[C.BLK-Files from theise GRASSSS  
> user list.
> 
> We are using GRASS 4.0 on a DEC5000. Can somebody help me?
> 
> Lars Flemming 
> Student of Computing Science
> Technical University of Dresden
> Germany


I am trying to understand what the exact question is and figuring out the 
different solutions to it. Original LANDSAT file could be in either BIL or BSQ
format, but it could not be a "LAN" file which is the ERDAS multi-band image
format in the BIL format (the file header is different from original 
LANDSAT BIL tape format). Also, GRASS never recognize ".BLK" format, which is
used by ERDAS to run "LDDATA" from a disk file.

As what I understand, you want the image files ending up at GRASS.
Here is my suggestions:

(1) If you still have the original LANDSAT tape, don't even bother with ERDAS,
just use GRASS "i.tape.tm" load the image directly into GRASS;

(2) If your file is already in ERDAS "LAN" format and there is ERDAS software
on your site, just run ERDAS command "cvt73" to convert header file from 7.4
to 7.3 version. (Also you have to run ERDAS "bstats" to build trailer file).
If you have ERDAS "GIS" file, please do exactly same thing.

    Then, fire up GRASS, run GRASS "r.in.erdas" to load your ERDAS "LAN" file
into GRASS.
    
    If your GRASS package doesn't have "r.in.erdas" command, you have to modify
your file in ERDAS by using ERDAS "DPDATA" to convert "LAN" file to original
LANDSAT tape format (you could output to a disk file). Then use GRASS
"i.tape.other" command to load this file into GRASS. Please enter the file name
when "i.tape.other" ask you for the tape device name. All parameters you need
to run "i.tape.other" is available from an output of ERDAS "LISTIT" command;

(3) The worst thing you can have is that there are not either ERDAS software or
"r.in.erdas" command on your site, but you have a ERDAS "LAN" file. In this 
case, you have to be a little more smart. If you can write a small program to
tape first 128 bytes header off LAN file, you can use "i.tape.other" to read in
the modified file directly with BIL option;

In worst of the worst situation, Just use "i.tape.other" to directly read in
the ERDAS "LAN" file which would have coordinate offset or margin cutoff, but 
you still can use a reference layer in GRASS to "i.rectify" to adjust it.

(4) If you get the real ERDAS "BLK" file, you should be able to use GRASS
"i.tape.other: command directly load into GRASS without trouble. Don't forget
put a full disk file name to it when GRASS asks for a tape device name. 


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