Building OSSIM

OSSIM is a powerful open source geospatial image processing package that builds under just about any modern platform. OSSIM provides several useful command line applications with the library that can be used to script large image processing tasks.

Building Under Gentoo Linux

The OSSIM folks don't release frequent and stable images of their source tree so the easiest way to get the most up to date code and any fixes that have been applied is to build the library and executables out of their SVN tree. I've written/modified 2 ebuilds that are necessary for the build to work. Portage can take advantage of 3rd party ebuilds like this by using the PORTDIR_OVERLAY variable found in /etc/make.conf; this variable must point to a location on the file system where the ebuilds are stored, mine states: PORTDIR_OVERLAY="/usr/local/overlays"

For the purpose of building OSSIM create the following directory structure under your overlay directory:

sci-geosciences/ossim

and

dev-cpp/osg

Now, download the Open Scene Graph ebuild into your overlays/dev-cpp/osg directory and the OSSIM ebuild into your overlays/sci-geosciences/ossim directory

• osg-2.2.0.ebuild: Open Scene Graph E-build for Gentoo (required for OSSIM)
• ossim-1.7.0.ebuild: Ossim Ebuild for Gentoo (builds out of the Subversion repository)

(note: these ebuilds are pretty complete but they may not have all of the dependency requirements written in - if the ebuilds don't build let me know and I'll modify the ebuild to include the missing requirement)

A digest must now be generated for each ebuild so that portage will know about the ebuild and make it available for building. Navigate to each of the directories where the ebuilds were downloaded and execute:

ebuild "name of ebuild" digest

Open Scene Graph contains OpenThreads^? which is necessary for parts of OSSIM to build - the ebuild masks the package so it is necessary to use the ~x86 or ~AMD64 to allow portage to build the package

OSSIM can be built with the stand alone library/command line apps only or with the graphical user interface (iview/imagelinker) and gdal plugin (useful for reading image formats other than just TIFF). Placing "ossim_qt" and "ossim_plugins" in the USE flags in make.conf will build and install these features. The OSSIM ebuild also requires OSSIM_SVN_REVISION to be set in the shell or in make.conf - set OSSIM_SVN_REVISION=HEAD to build from the most up-to-date version of the subversion tree.

Typing: emerge ossim

should now build all the dependencies, download OSSIM from SVN, and build & install the code.

-- JasonFaulring - 16 Oct 2007