[MEncoder-users] Converting wmv to wmv

[The Wanderer]

Lennart Börjeson wrote:

> tisdag 18 april 2006 03:46 skrev Ko Ko:
> 
>> Hi
>> 
>> I tried your -of lavf and it works! But sadly with a bit of
>> problems.
>> 
>> I tried like
>> 
>> "mencoder -of lavf -oac mp3lame -ovc lavc -lavcopts vcodec=wmv1 
>> -ofps 100.0 test.wmv output.wmv"
>> 
>> I can't use wmv2. It doesn't render. I can't use copy for audio.
>> Doesn't matter as well. But the movie was playing back too fast.
>> Just like it is being 'fast forward'. I am not too sure why. Is it
>> because I -ofps 100.0? I don't know what is the purpose of using
>> this. But if I don't set this it doesn't produce wmv.
> 
> wmv supports a variable frame rate, but mencoder doesn't. In fact,
> mencoder requires to use a fixed frame rate, either by default from
> the input or by specifying it explicitly.
> 
> 100fps is improbable. If your video material orgininates from
> "normal" video or film, it will be, in average, either 30, 25, 24 or
> 15fps (or the absurd 1000/1001 NTSC fractions thereof), and you
> should specify -ofps 30 or whatever matches your input.

Err... '-ofps' specifies the frame rate you want the output to have; it
has, or by my best understanding should have, nothing whatsoever to do
with the input frame rate (which you cannot change except by using a
different input file).

(And while it may be correct to describe NTSC's repeating-decimal frame
rates as absurd, it is also likely to confuse the uninitiated user, who
may then think that they are incorrect and should not be used; they
*are* the correct values, even though they don't make a lot of sense
from a modern technical perspective, and using other values can and IME
does produce undesirable results.)

-- 
       The Wanderer

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

Secrecy is the beginning of tyranny.