[MEncoder-users] mp4 audio slipping when played back in Quicktime

[Bram]

> >I'd like to jump in here for a sec.. how would you go about and encode
> >both audio and video as separate streams using just mencoder? I couldn't
> >figure out how to get mencoder to just encode audio, for instance.
> 
> You may very well be right here. At the moment I am more into ffmpeg and 
> mplayer (!) for transcoding purposes.
> 
> At least, indeed, it's not possible to have mencoder output raw audio 
> and raw video streams at the same time.
> 
> It may be that mencoder also cannot output audio only, but isn't that 
> work-around-able by specifying null video output somewhere?
> 
I don't remember the exact messages anymore, but I tried several
methods, all of them resulting in mencoder complaining about the lack of
video.

> The final workaround which most certainly will work is to have mencoder 
> encapsulate in avi and then demux that avi using ffmpeg ;-)
>
Yes, that would probably work indeed. I think that's how the whole
'frameno.avi' bit works, although that appears to have a hardcoded
output filename.

> Anyway, if you only want to transcode audio, I think ffmpeg is a better 
> option anyway. Also if you're transcoding from pcm(wav) to aac, I'd 
> rather use the faac program directly (until ffmpeg has a native aac 
> encoder).

The thing I'm worried about there, is that perhaps ffmpeg/mplayer/faac
do not accept the same input video formats. Or parse them differently.
In my case, I don't have control over the input video, and therefore I
may (and do!) receive the weirdest formats. So far, it seems mencoder
'wins' in understanding most formats, though it does need more hinting
(e.g. supplying specific demuxers on the cmdline for specific video
formats, etc). So it would be nice if just 1 tool demuxes and/or decodes
all the video files.

I actually hope I'm wrong in thinking that mencoder understands more
video formats than, say, ffmpeg. Since in my experience, ffmpeg
auto-analyzes the input videos better. But as I understand mencoder
should be able to handle input videos that *require* a windows dll for
decoding, whereas ffmpeg does not have that option. So mencoder by
definition is better suited. Or am I wrong here, and can all codecs that
mencoder understands be decoded by ffmpeg as well?

Bram