Remote Sensing Tools

In the first tutorial, Geotiff & Photoshop, Part 1; we went through the steps of using the listgeo and geotifcp commandline utilities to dump the metadata of a Geotiff .tif file, and how to re-stuff the metadata contained within the output text file back into a .tif image saved out of Photoshop®. But what if you’re still worried about using a command prompt program to do this task, or you might have difficulty training someone to use the commandline? Or perhaps you’re simply not ready to take on using commandline utilities? There is an easier solution, if you install a simple program that uses a standard Windows interface.

Update!

GeoSage, the developers of HighView, an advanced pan-sharpening and image fusion program, have contributed the following easy to use GUI program that runs the same basic listgeo and geotifcp functions that I described in the previous tutorial. It’s freely available to anyone through the Geotiff developer’s Web site here:
http://www.remotesensing.org/geotiff/

Or, for your convenience, you can directly download the appropriate package that contains the installer:
ftp://ftp.remotesensing.org/geotiff/libgeotiff/listgeo_GUI.zip

After you’ve installed the program, open it and be sure to click the Notes button to read the information regarding the program. It’s always a good idea to get as much information about a program prior to its operation, as it might be useful in providing clues to its operation that you might otherwise miss.

When you initially open the program, you’ll notice two distinct groupings in the interface:

• 1. listgeo.exe - to dump geotiff metadata to a file
• 2. geotifcp.exe - to copy tiff with updated geotiff metadata

The following usage guide will walk you through what to do.

Prerequisites

As in the last tutorial, you’ll need a Geotiff image to work with. If you don’t have one available, I’ve provided a sample Geotiff file here:
Sample Geotiff (~350 KB download, .zip format)

Usage - listgeo

1. Click the button to the right of the first text field, to browse to the location where your Geotiff image is stored — and the image filename will appear in the field.
   • (The image name will also appear in the field titled Enable Esri “-tfw” option, but we’re not concerned with this, so we’ll ignore this option by leaving it unchecked.)
2. Click the listgeo button.

That’s it! You should now have a text file in the same folder directory as your image, with the same filename as your Geotiff .tif image — but with a .gtf extension.

Usage - geotifcp

Running the geotifcp command is rather easy and straight-foward as well. Simply do the following:

1. In the GeoTIFF metadata field, browse to your .gtf text file that has the metadata you wish to install into your non-geocoded .tif image.
2. In the Input TIFF field, browse to where the non-geocoded .tif image is that you’ll be installing the metadata.
   (eg: the image you output from Photoshop)
3. The Output GeoTIFF field should automatically include the name of your final Geotiff file, but with the ammendment of _gf at the end of the filename.
   (You can change this ammendment if you wish.)
4. Click the geotifcp_1 button.

That’s it! Now, you should see the resulting Geotiff .tif image in the same folder as your other files, except with the ammended filename.

Caveats

As was noted in the previous tutorial, using listgeo and geotifcp does come with some consideration. Image resizing and/or cropping is not recommended in any image editing program that does not support geospatial imagery. This can lead to various problems in your final Geotiff image or make the images incompatible with GIS viewers and editors.

However, if this is your only method to work with geospatial imagery, you can still use the methods described using listgeo and geotifcp to enable yourself the ability of working with Geotiff imagery in industry standard editors, such as Photoshop.

More to come…

In the next tutorial, Geotiff & Photoshop, Part 3; we’ll explore the common options in using an actual GIS program to handle metadata from Geotiff files, so that we can then be able to import our imagery into Photoshop or other image editing tools.

For More Information

For more information on the GUI program mentioned in this part of this four part series, you can visit the developer’s page at the following Web site address:
http://www.geosage.com/highview/download_3.html