How to detect interlaced frames, between mixed with progressive frames

[nicmar]

This Super8 capture, seems contains interlaced and progressive frames.
I think, it's due to the 25fps output conversion, from the 18fps Super8 input format.

How can i detect, and then, remove the interlaced frames.

The frame sequence is like (P for Plain, I for Interlaced):
P P I P P I P P I ...
but it is not a regular sequence !

Here is the example :
http://nicmar.fr/media/s8.avi

[manono]

http://nicmar.fr\media\s8.avi
Server not found

Something's wrong with that link, for me anyway. And you capped it as an AVI? And why didn't you cap it at 18fps?

[nicmar]

It's seems OK now ...

http://nicmar.fr/media/s8.avi

It's a family DVD, from an old Super8 in 1970.
I don't now who made the capture.

[manono]

There are a lot of field blends in there. I'd do it something like this:

Yadif(Order=0,Mode=1)#or your favorite bobber
SRestore(FRate=18)

Maybe someone else has a better idea. This script results in some duplicate frames, like the original framerate might be less than 18fps (a bit over 17fps, I would guess). I don't notice any missing frames (although there may be some).

[MrVideo]

It's a family DVD, from an old Super8 in 1970.

It will be 100% interlaced. MPEG-2 video can only be interlaced or progressive, it can't be both.

It can "look" like it has progressive frames because at the time of transfer, a single film frame was captured on both fields.

That is no different than 2:3 pulldown in that in a high motion area of the video, two frames will definitely look interlaced and three frames will look progressive, but they aren't.

[nicmar]

Thank you for your suggestion,
so there's nothing to do, to detect interlaced frames ?