[MPlayer-dev-eng] Custom soft-telecine patterns

[D Richard Felker III]

On Thu, Mar 17, 2005 at 08:38:25PM +0200, Ville Saari wrote:
> On Thu, Mar 17, 2005 at 05:56:18PM +0100, Nico Sabbi wrote:
> 
> > a) 3 0 1 2 2
> > b) 2 2 2 2 2
> ....
> > it seems that using pattern a) it's possible to telecine 25 fps 
> > progressive video to 30 fps,
> > and with pattern b) 25fps -> 29.97
> > 
> > It sounds convincing. Is it really? :)
> 
> A better pattern for 29.97 fps would be:
> 
> a) 3 0 1 2 2  repeated 83 times
> b) 3 0 0 0 0  once
> c) 1 2 3 0 0  repeated 82 or 83 times
> d) 1 2 2 2 2  once
> 
> Instead of omitting two consecutive repeats once every 1001 frames,
> this would omit just one every 1001 fields. The resulting artifact is
> less visible.
> 
> But what would anyone need this for? This kind of processing won't
> work for interlaced video and if you have progressive material at
> 25 fps, you most likely have sped up film, for which it is much
> better to just interpret the framerate as 23.976 and then use the
> usual field flag pattern.
> 
> A more general solution would be to accept an arbitrary input fps
> between 20000/1001 and 30000/1001 inclusive and then just insert an
> RFF and invert the polarity whenever you are more than half a field
> behind the schedule. This would actually apply one-dimensional
> Floyd-Steinberg dithering to frame durations.

Your email is almost exactly the same as mine. :)
Except you put in a little more detail and a little less flame. :)

Rich