[MEncoder-users] Weird DVD with shifting framerates

[R.L. Horn]

On Wed, 12 Jun 2013, Carl Eugen Hoyos wrote:

> R.L. Horn <lists <at> eastcheap.org> writes:
>
>> ...does ffmpeg have a telecine-aware deinterlacer?
>
> I am not sure if I understand the question:

A lot of NTSC DVD streams go back and forth between soft telecine and "60" 
field/sec interlaced.  Sometimes, the best way to deal with it (e.g. for 
short interlaced bursts from sloppy editing) is to constrain the whole 
thing to 24000/1001 fps, discarding frames when necessary, and smoothing 
over the interlaced frames, while leaving progressive frames untouched.

> The inverse telecine filter is able to call a deinterlacer for frames 
> that could not be inverse-telecined,

If it's smart enough to leave existing progressive content alone, then, 
yeah, that would be what I was describing.  My (possibly faulty) 
recollection is that mencoder would detect soft pulldown early on and 
blindly feed a mix of progressive and interlaced content into the filter 
chain, which made dealing with NTSC weirdness problematic.  I don't know 
if that's the case with ffmpeg.