[MEncoder-users] Inverse telecine? framerate from 120000/1001 to 24000/1001

[Loren Merritt]

On Thu, 31 Aug 2006, Evgeniy Stepanov wrote:

> On Thursday 31 August 2006 05:07, Rich Felker wrote:
>> Yes, what you said is nonsense. The reason the file uses 120 tick/sec
>> timebase is that it's not all 24 fps but some 30 fps, and the smallest
>> common timebase that can represent timestamps correctly for both is
>> 1/120 sec. If you try to make it 1/24 sec timebase, you will have to
>> discard one in every five frames from the 30 fps parts. If you want to
>> make it 1/30 sec timebase, you will have to show every 4th frame in
>> the 24 fps parts for double duration. Both choices will look very
>> ugly and choppy.
>
> It might be a good idea to somehow locate the parts of original video that are
> 24 fps and the parts that are 30 fps, and encode them separately. Then,
> either leave the resulting videos as they are, or mux them into some vfr
> container.
>
> AFAIK, there is no good way of converting 30 <-> 24 fps.

No need to separate anything. Just encode it as 120fps with null frames, 
and then remux to a vfr container. mkvmerge at least will do the Right 
Thing.

--Loren Merritt