transcode is a text-console utility for video stream processing.
Decoding and encoding is done by loading modules that are responsible for
feeding transcode with raw video/audio streams (import modules) and encoding
the frames (export modules). It supports elementary video and audio frame
transformations, including de-interlacing or fast resizing of video frames
and loading of external filters.

Requires ffmpeg, libmpeg2, lame, libdv, libdvdread and a52dec.
If you don't want support for libquicktime you'll have to pass QUICKTIME=no
to the script.
All dependencies are available from SlackBuilds.org.