imlib2 is part of the Enlightenment EFL libraries. It is built using ./autogen.sh, configure and make. In the initial build it is missing support for gif and id3, gif support is added by installing the giflib-devel package, id3 support needs a new project, id3lib.
The id3lib project is required for the imlib2 project, it lives in cvs at sourceforge. It is built with ./configure, make and make install. This project appears not to be under active maintenance in the sourceforge CVS repository.