[Theora-dev] DVD->OggTheora

[S Clark]

<200407011305.01146.Chilling_Silence at orcon.net.nz>
<87d63gktmp.fsf at snail.Pool>
Message-ID: <200407011025.12177.mail-lists+theoradev at dogphilosophy.net>

On Thursday 01 July 2004 02:40 am, David Kuehling wrote:
[...]
> >> How do I encode DVD to theora without storing huge raw files on the
> >> disk?
> >
> > In a nutshell: AFAIK - You cant!
>
> Using mplayer, you can.  The following code only needs temporary storage
> for the audio.  Actually you could get around the temporary storage by
> using another mplayer-process in a pipe for audio.  However, for DVDs
> this is utterly slow and sometimes hangs on my system.  You can
> optimized more, by storing only the compressed MP2-audio on disk and
> using another mplayer-decoding pipe when creating the .ogg.  The
> following script I'm currently using for encoding a the Chihiro DVD
> (encoding not completed yet...):
[...]
You don't need two separate mplayer processes to handle the audio:

mkfifo stream.yuv
mkfifo stream.wav

encoder_example -a 2 -v 7 stream.wav stream.yuv > theora.ogg &
mplayer -vo yuv4mpeg -ao pcm -aofile stream.wav dvd://1 2&>1 >/dev/null

encoder_example should then grab both the audio and video as they're decoded
by mplayer.  I use a variation of this process to re-code high-bitrate mpeg4
video capture to SVCD for archiving, using the encoders from the mjpeg
project.  I've not tested this with theora directly from DVD, but have used
the same procedure to transcode other media to theora before.