DVD Deinterlace issues after framerate adjustment: motion choppy

[ikarus2k]

Hy everybody. I tried everything I could and read most tips (I think/hope) but still haven't figured this one out.

I am re-encoding a 29.97 fps DVD (with interlacing, obviously) into a 23.976 fps DivX. I tried to deinterlace with following VirtualDub filters (sweeping through all options/value ranges):
Deinterlace [internal] - a very bad choice, won't do it again
DeinterlacePAL - some vertical lines remain (very large ones), quality unacceptable
DeinterlaceMAP - best so far, but frames appear choppy (as in the 4th and 5th frames are identical). at 29.97 fps it's not that clear, but at 23.976 it's terrible (I am using low values for the filter

Please don't shoot me if this question has already been asked, sorry; any advice is appreciated. Thanks!

[Guest]

If it's film source, you should be doing IVTC, not deinterlacing.

[ikarus2k]

Finally (and sadly) back from the hollidays.

Thanx neuron2. DvD2Avi tells me it's a 0,00% Film (Video Type: NTSC), so I assume it's a pure interlaced clip (since it's a tv series I should be right).

The thing is, VirtualDub(Mod) both give me an error message (error: 80040154) everytime I want to load an *.avs. So what I did was to use DeinterlaceMAP and a 3:2 puldown (inverse telecine) in VirtualDub to achieve the desired effect. Hope this info helps somebody.

[Guest]

I assume it's a pure interlaced clip...

...So what I did was to use a 3:2 puldown (inverse telecine) That's totally self-contradictory and makes no sense.

[ikarus2k]

Sorry, my bad. I DID an inverse telecine (IVTC just like you suggested) but thought it was the same thing as a 3:2 pulldown [removal] (or am I acting like Jessica Simpson again?).

[Guest]

Sorry, my bad. I DID an inverse telecine (IVTC just like you suggested) but thought it was the same thing as a 3:2 pulldown [removal] (or am I acting like Jessica Simpson again?). Yes, you are. IVTC = 3:2 pulldown removal.

If the video is pure interlaced, as you claimed, you *should not* do IVTC.

[ikarus2k]

ok, I know IVTC = 3:2 pulldown removal (I forgot to write it).

so what would you say to Jessica for a foolproof way to determine if it is or not interlaced. if it is, why does IVTC work?

[Guest]

so what would you say to Jessica for a foolproof way to determine if it is or not interlaced. if it is, why does IVTC work? You're the guy that said it was pure interlaced and then in the same post said you did IVTC! Why would you do IVTC on a pure interlaced source???

To see if something is interlaced:

1. Make a AVS script that serves the video.
2. Add separatefields() at the end of the script so that you can step through the fields.
3. Serve the script to VirtualDub and step through the fields in a section with constant motion.
4. Denote a picture as a letter, e.g., 'a'. If every field is a new picture, you'll get this for your field sequence:

a b c d e f g h ...

That is pure interlaced video.

You may see this:

a a b b c c d d e e ...

That is progressive video.

You may see this:

a a a b b c c c d d e e e ...

That is 3:2 pulled-down progressive video.

[ikarus2k]

thanks and a BIG sorry for the hassle.