In a typical WASP scenario:

• WASP lands, and its main flight drive is removed and taken to your ground processing location.

• There, it is mounted onto hercules, where it is shared on the local network via SMB as ADP.

• The files are initially in ENVI format. We need to translate them into GeoTIFF or Imagine format, so that they can be further processed by the system, or so that people can load up the individual orthos and examine flight data before the big mosaics are produced. You'll do this conversion typically on your laptop, connected to the shared filesystem from hercules.

Your job, then, is

Set Up GDAL On Your Laptop

OS X

We do this via Mac Ports (this project used to be called Darwin Ports).

Assuming your install of Mac Ports is recent enough, you should be able to configure and build GDAL and its related tools on your laptop with a single command:

sudo port install gdal

Once installed, you should mess around with the gdal_translate utility a little bit, to ensure that things are working as you'd expect.

Linux

Windows XP

Network Configuration

You can connect to the LIAS Ground Station network (where hercules should be connected) either through wired or wireless interfaces. Assuming that the ground station's Linksys hub is being used, you'll be assigned an address via DHCP automatically. However, if you want to do things manually, take an address between 192.168.0.30 and 192.168.0.99 --- anything higher is reserved for DHCP, and anything lower is reserved for static addresses of well known systems.

You likely will not have working name resolution; if so, refer to hercules by its numeric IP address: 192.168.0.10

Mounting ADP filesystem

Once hercules is online with the WASP drive, it will be shared as ADP on the local network via SMB. Mount this drive on your laptop:

OS X

From the Finder, hit Apple-K or choose Connect To Server under the Go Menu.

Connect to smb://192.168.0.10/ and select the ADP filesystem. If a user and password are required, it will probably be the standard account used for WASP acitivities, but check with Jason to make sure.

Typically, the new filesystem will be mounted under /Volumes using the name of the shared directory. So, from your Terminal, you could get to that filesystem with something like cd /Volumes/ADP.

Windows XP

Linux

Converting Files

Typically, someone (like Jason) will give you directories or hierarchies that need to be converted. There might be an order, a preference, of which flight legs are converted ahead of others (for example, one leg might have something interesting in it that people want to see first).

So, you're typically going to be given a directory of ortho'd images and a file format to convert into. You should also agree to a location where you're going to store the converted files; it may or may not be the same directory. Nota Bene: ENVI uses .hdr and .img for its file extensions, GeoTIFF uses .tif, and Imagine uses .img. Therefore, if you are going to convert ENVI into GeoTIFF, the new files can be stored alongside the old ones. But if you are going to convert ENVI to Imagine, then the new files must be stored in a different directory, or else you will overwrite the flight files. You're working on raw flight data, and it hasn't been copied or backed up yet, so you must be careful.

The typical format of a file conversion is

gdal_translate -of OutputFormat SrcFile DstFile

So, for example, to convert a single file from ENVI to GeoTIFF format, you might do something like the following. Note that GDAL refers to the GeoTIFF output format as GTiff and to Erdas Imagine format as HFA. No, I don't know why.

gdal_translate -of GTiff Geo123.img Geo123.tif

Notice a few things about that command. You name the .img portion of an ENVI data pair, and GDAL works out the format of that source file. Also, in that example, we stored the resulting GeoTIFF format in the same directory. If we were working with Imaging format, you might do something differently. For example, at one point in the past, we were storing Imagine files in a subdirectory of the ortho'd imagery. So, in that case, we might have done

gdal_translate -of HFA Geo123.img Imagine/Geo123.img

Note that both the source and destination files end with .img. Annoying, isn't it? Actually, though, it works in our favor, making life simpler when we're converting to Imaging format, as you'll see below.

It might be better to store the resulting files in a sibling directory, rather than a subdirectory. For example,

gdal_translate -of HFA products/Geo123.img imagine/Geo123.img

From this point on, I'm just going to share some "recipes" for doing these conversions. I'll try to give the examples for both kinds of shells. Those lines that start with a $ are for Bourne-family shells (sh, ksh, zsh, bash). Those that start with a % are for C-family shells (csh, tcsh).

Recipe: Convert all the ENVI files in the current directory to Imagine format, storing them in another directory. Takes advantage of the fact that both ENVI and Imagine formats use .img as their file suffixes.

$ for f in *.img; do
> echo $f
> gdal_translate -of HFA $f ../imagine/$f
> done

% foreach f (*.img)
? echo $f
? gdal_translate -of HFA $f ../imagine/$f
? end

Recipe: Convert all the ENVI files in the current directory to GeoTIFF format, storing them in the same directory (alongside the source files).

$ for s in *.img; do
> echo $s
> d=`basename $s .img`.tif
> gdal_translate -of GTiff $s $d
> done

% foreach s (*.img)
? echo $s
? set d=`basename $s .img`.tif
? gdal_translate -of GTiff $s $d
? end

Recipe: Convert all the ENVI files in the current directory to Imagine format, storing them in a different directory named FOO. Replace FOO with whatever directory you want to use: for example, ../imagine or /Volumes/ADP/foo or whatever.

$ for f in *.img; do
> echo $f
> gdal_translate -of HFA $f FOO/$f
> done

% foreach f (*.img)
? echo $f
? gdal_translate -of HFA $f FOO/$f
? end

Recipe: Convert all the ENVI files in the current directory to GeoTIFF format, storing them in a different directory named FOO. Replace FOO with whatever directory you want to use: for example, ../imagine or /Volumes/ADP/foo or whatever.

$ for s in *.img; do
> echo $s
> d=`basename $s .img`.tif
> gdal_translate -of GTiff $s FOO/$d
> done

% foreach s (*.img)
? echo $s
? set d=`basename $s .img`.tif
? gdal_translate -of GTiff $s FOO/$d
? end