[MPlayer-users] Re: [-] Re: [-] Re: [-] Crop before deinterlacing OK?

[Matthias Wieser]

Am Samstag, 23. Juli 2005 04:24 schrieb Rich Felker:
> On Sat, Jul 23, 2005 at 12:35:53AM +0200, Matthias Wieser wrote:
> > Am Montag, 18. Juli 2005 15:03 schrieb Guillaume POIRIER:
> > > Hi,
> > >
> > > I fought quite a bit against NTSC content for the past week. From
> > > my perspective, even thought ivtc doesn't _harm_ strictly speaking
> > > when the content is not telecined, putting it "blindly" is not what
> > > I'd recommend.
> >
> > What about those standard deinterlacers? I think about kerndeint or
> > pp=md. Motion would probably not be as smooth as with an inverse
> > telecine filter but would it be scceptable for a normal-quality TV
> > recording?
>
> Depends on whether you care or not. 30fps deinterlacers destroy the
> content really bad, and look particularly bad with telecined content
> since it will be both choppy and low-resolution afterwards.

OK.

> Your only 
> hope of good results with deinterlacing is to use a 60fps
> deinterlacer, i.e. tfields.

This will be included into an additional profile for Kalva.

> > > That's because when you ivtc, you most of times change
> > > framerate back to mostly the original framerate of the movie. Now,
> > > if you do not set the correct output framerate with "-ofps", you'll
> > > either end-up with duplicate frames
> >
> > How does it look like? I could imagine that those CNN live tickers
> > would show some unsteady motion if frames were duplicates. But does
> > it matter for movies?
>
> Yes, especially during pans.

When will Mplayer be able to smooth the GMC vektor during playback? ;-)

> > > So please-please-please, identify your source before launching the
> > > encoding process.
> >
> > Hm, quite a challenge when doing timer based TV recording!
>
> For live recording you should not do any processing, but keep it in
> the original (interlaced) format. Then you can reencode later to
> restore it to something watchable.

Maybe some later version of Kalva will provide a GUI for that task. But 
for the mean time...

> > But let's assume someone is recording a movie. Would detc be an good
> > option? The manpage says that ivtc does not like noisy input.
>
> It really depends on how bad your TV signal is. Cable (with a good
> connection) or satellite should be fine. Terrestrial analog broadcast
> may be good or bad depending on the user's antenna system and the
> proximity to the station.

Then I will choose detc as default.

> > What would be an good option for the daily soap opera? ivtc together
> > with -ofps 30000/1001, or better detc (any advice for the
> > sub-options?) with -ofps 30000/1001?
>
> No, soaps are not telecined as far as I know;

That's what I thought, too. But see my mail from 07.07.:
---
[I wrote:]
> I thought you only need to inverse teleine when capturing NTSC movies. 
> Normal NTSC TV broadcasts can be deinterlaced with pp=[md|lb...], right?
[You wrote:]
It depends on the content. You have to painstakingly check every
single thing you encode.
---

Do you think it would work for *most* (not all) live recordings to provide 
two profiles: one with detc and -ofts=~24 and another one with kerndeint?

Regards,
  Matthias