NITRO (NITFio, "R" is a ligature for "Fi") is a full-fledged, extensible library solution for reading and writing the National Imagery Transmission Format (NITF), a U.S. DoD standard format. It is written in cross-platform C, with bindings available for other languages.
Several TREs are now "preloaded," but they are all disabled so that existing functionality is preserved.