I was wondering if anyone knows of an open source, perferabily something for QGIS and not GRASS, that can be used for orthorectifying scanned archived air photos. I have looked at OSSIM and a few other packages, but they do not allow (from what I can tell) for a single image to be processed based on user input from a geoimage or vectors. Packages like ERDAS and PCI allow for this, but I am looking for an open source solution. The Georefrencer plugin to QGIS is good, but I would like to be able to use a DEM (digital elevation model) as a source for the Z information for terrain relief issues.
Any help would be great, or clarification on OSSIM or other products that I may be misunderstanding.