[MEncoder-users] Ripping dvd to mp4

[Grozdan Nikolov (openSUSE Linux)]

On Tuesday 25 March 2008 18:21, Erik Slagter wrote:
> RC wrote:
> >> I'm saying that mencoder cannot hardcode subtitles coming from a DVD
> >> (mpeg program stream) while transcoding without the use of several
> >> steps  involving temporary files holding the subtitles.
> >
> > I haven't the slightest idea what could possibly make you believe that.
>
> Some people at the devel mailing list, like I said before. But maybe in
> the meantime mencoder has been enhanced with this functionality. See the
> other messages.
>
> >> But as said before, mencoder cannot handle B-frames in mp4 (nor any
> >> other lavf-container). This can be worked around using elementary
> >> streams and then mux using gpac, but this can and will sooner or later
> >>  screw up your a/v sync because timestamps are lost. That's why I
> >>  really want to have one single program that does it all in one pass.
> >
> > MP4Box doesn't need elementary streams.
>
> In theory: indeed. In practice: it tends to choke on various containers.
> All of my transport streams make mp4box segfault and large mp4 files
> also tend to do unsane things to mp4box. And I'd rather not use avi
> files if you don't mind, especially when big.
>
> > Seperate A/V streams doesn't inherently mean losing sync.
>
> In practice it does. For example: if you rip part of a DVD, the audio
> and video will be skewed (this more or less follows from the
> requirements on DVD's). With the timestamps, this is no problem. Without
> the timestamps you're screwed. Sometimes this even happens when copying
> a full DVD.
>
> Same goes for transport streams received by DVB, they tend to miss a
> video or audio frame once in a while. Without the timestamps, you're lost.
>
> Once I had a "solution" involving projectX, which indeed guarantees that
> you can use the elementary streams without a/v sync issues, BUT the
> timestamp-straightening algorithm appears to be a little bit too
> aggressive, so it constantly keeps dropping and duplicating frames when
> the timestamps are just a little bit off. This is annoying in panning
> scenes. Also I don't like java apps for various reasons :-/
>
> Anyway, to cut a long story short, there doesn't seem to be the
> "elegant" solution to my problem I was hoping for. Maybe mencoder might
> help a bit, I will have a look at this.
>
> Sadly most countries audio-dub their DVD's so there is little interest
> in subtitling by the developers of multimedia applications.

Have you tried playing around with avidemux? 

-- 
Regards