The German Nation Library of Science and Technology (TIB) runs a digital archive in order to preserve its digital holdings which consists amongst others of audio-visual material. In order to identify obsolete audio-visual file formats a catalogue of criteria is developed and file formats which represent the majority of TIB’s audio-visual holdings are examined. The assessment reveals that the examined file formats are not a preferred file format for digital preservation, but on the other hand they are not at risk to become obsolete to TIB’s designated community. Furthermore, a migration plugin for the digital archive’s software environment is developed and successfully deployed. The migration plugin can be used during preservation planning in order to migrate the examined formats into TIB’s chosen archival file format if a migration becomes necessary.