>> Mencoder can only output reliably to avi (not even separate raw video
>> and audio stream, simultaniously...) while mp4box (gpac) cannot handle
>> h264 in avi, so...
> Nonsense. I use mencoder to encode to mp4 containers all the time, and
> without AV synch issues. I just don't use b-frames.
That's the whole point. For any (output-)format other than avi and mpeg
(program stream/transport stream?) mencoder uses lavf, which in itself
handles b-frames well, but mencoder in combination with lavf doesn't.
So, output to mp4 with b-frames, no way.
B-frames are there for a reason... There is no industry conspiracy that
makes you believe you cannot live without b-frames even though they only
cost you money. Anyway, b-frames are a requirement for me and thus I
cannot use mencoder to output mp4, that's all there is to it.
The a/v sync issues start to come when you need to output to raw video
and raw audio (because you cannot use the mp4 muxer etc.)
> Having said that, I am coming around to the idea that h.264 is not the
> be-all and end-all of video encoding that some people think it is. I've
> been using mpeg4 for HD encodes (720p) because the artifacts are not as
> annoying as those from h.264. To my eyes, mpeg4 seems "truer" to the
> original source. I use h264 for those applications and devices that
> require it (ipod/iphone).
h264 has a few interesting practical points compared to mpeg4-2 imho:
- almost always encapsulated in mp4, which has clean support for
b-frames (and b-frames as references!), so far less prone for
incompatibility issues in this area;
- altogether far less stories on incompatibility due to certain vendors
implementing their own "extensions" upon a subset of a _standard_ and
then branding it as their own ("DivX");
- "mpeg4-2 is a failed experiment" (quoting Måns Rulgård here, quoting
the broadcasting industry)
- I expect less and less new hardware devices supporting mpeg4-2.
and a few more, gut-feeling like things I won't bother you with.
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