[MEncoder-users] Mencoder params

[Raimund Berger]

John Doe <jdmls at yahoo.com> writes:

>> > (1) You don't need to encode audio on the first pass. To save cpu
>> >     cycles, rather use -oac copy
>> 
>> Quite the contrary.  Changing the audio encoder will very likely cause
>> different frames to be dropped, resulting in lower quality 2-pass
>> encoding, and potentially the second-pass crashing as well.
>
> Indeed, I put -oac copy in the 1st pass and got:
> x264 [error]: 2nd pass has more frames than 1st pass (400):0.023 [1019:102]]
> x264 [error]: continuing anyway, at constant QP=36
> .... Segmentation fault

That's really very interesting. As you got such a source, and if you
incidentally find the time, I'd be interested if
"-mc 0" applied on both passes or
"-oac pcm" applied only on the first pass
would change anything.