[mythtv] mythtranscode -> avi

[Torbjörn Jansson]

> However, since mplayer (and transcode, and ffmpeg) still
> continue to NOT
> support myth's nuv files, there is currently no way to convert an nuv
> file to an avi file without transcoding/reencoding.

Not quite true, with my windows filters it's posibel to convert a nuv file
to avi without any kind of recompression.
There's no fancy gui for it (yet) so you have to use graphedit and build the
filter graph manualy.

But maybe you were refering to a linux solution.