[mythtv-users] transcoding perfect dvd rips to xvid

[David Brodbeck]

Mike Schiller wrote:
> Thanks, David.  I'm definitely open to non-ffmpeg solutions, I guess I
> shouldn't have been so restrictive in my posting.  Your mencoder
> solution look like an excellent solution to my problem.  I do have a
> couple of quick follow-up questions:
>
> I take it that I just replace dvd://2 with the input file name?
>   

Yup.  If you find you're not happy with the quality, you might want to
take a look at the stuff in this section:
http://www.mplayerhq.hu/DOCS/HTML/en/encoding-guide.html
There's a *lot* of info there about how to get the best quality when
transcoding DVDs, including deinterlacing and inverse telecine.

Oh, I just remembered...for transcoding MythTV files, I found I needed
to add "autoaspect" to the list of vcodec options.  This preserves the
aspect ratio encoded in the original file.

> Since it can handle anything mplayer can play, then is it safe to
> assume that it will automatically handle the number of input audio
> channels properly?
>   

The first example they give copies the existing audio stream without
making any changes.  That's what "-oac copy" means.  So if you start
with (say) 5.1 AC3 audio, that's what you'll get in the final file, as
well. 

> Does encoding the audio to MP3 preserve the number of input audio channels?
>   

That I'm not sure about.  I haven't tried MP3 encoding.  I like keeping
the AC3 audio around in case I ever switch to using SPDIF audio out. 
Also, MP3 audio seems to carry with it a higher risk that the video and
audio will get out of sync.