Opening file formats

[Jairo Amaral]

Hi, I downloaded the image files I wanted, but I'm having trouble opening them. The IMG files are supposed to be mounted, but they are always said to be "damaged". Is there a section describing how to deal with all the formats found in ODE?

Thank you.

[Dan Scholes]

Hi Jairo,

Thank you for emailing us with your question.

You are receiving the “corrupted file” response because your computer does not have a native application for opening the PDS IMG files. Also, sometimes a cd/dvd image file is called an IMG, so an application used for mounting disk images tries to open the file in a different expected format.

A typical PDS image is stored as a simple binary array. It is described by a PDS label (a set of ASCII-text keyword=value statements), which can be either attached or detached. An attached label is embedded at the beginning of the image file; a detached label is in a separate file with the same name, extension LBL. The label tells you everything you need to know to read the image -- the number of lines, number of pixels (samples) per line, the size and data type of a sample, and map projection information if the image is a map. (PDS deliberately does not rely on any commercial or proprietary formats to archive image data, in order to ensure the long-term viability of the data.)

Typically IMG files are opened with programs including ENVI, NASA View, or GDAL. ArcMap might support IMG files, but I don’t remember. The IMG files can also be parsed and manipulated with code (Python, IDL, Matlab, C++, C#).

In the future, I hope to add functionality into ODE to allow a user to request the files in various formats, but it is not on the near list. In the meantime, GDAL is a standard application for changing formats.
http://www.gdal.org/ (general information and the link to download)
http://www.gdal.org/gdal_translate.html   (basic GDAL commands)

Here is an example commands that can be used to convert an img to tif:
Gdal_translate -of GTiff D:\test\data\MGN\fmap\fl13s309.img D:\test\data\MGN\fmap\fl13s309.tif

NASA View is better for just viewing images:
https://pds.nasa.gov/tools/about/pds3-tools/nasa-view.shtml

Let us know if you have any further questions.
Thanks,
Dan

 

[Jairo Amaral]

Thank you! I'll study this.