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Full Version: Mixed interlacing and frame blending – workflow recommendations?
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Hello,
I'm working on a PAL DVD source and I'm having trouble getting a clean encode.
The video appears to have interlacing issues and what looks like frame blending. I've tried several deinterlacing settings, but I can't seem to remove the artifacts without introducing new problems such as loss of detail, ghosting, or motion issues.
At this point I'm not sure whether the source is simply interlaced, field-blended, or affected by a PAL conversion process.
Could anyone take a look and advise me on the best approach? In particular, I'd like to know:
  • How to correctly identify the type of issue present in the source.
  • Which filters or settings should be enabled or disabled.
  • Whether deinterlacing alone is sufficient or if a more advanced restoration workflow is required.
  • Recommended settings for achieving the cleanest possible encode.
I've attached sample screenshots and/or a short sample clip.
Any advice would be greatly appreciated.

Sample: http://titant.free.fr/tmp/LH01.mkv
Screenshot: [attachment=3645]

PS: Selur, you've helped me in the past and I know you're very knowledgeable about this kind of issue. I'm sure you'll be able to point me in the right direction and help me figure out the proper solution.
Since when bobbing each frame is doubled the source isn't interlaced, but field shifted.
Looking at the separated fields, you see those are messed up.
[Image: grafik.png]
=> I'm looking at it.
Problem is that since the fields are already messed up there is not much you can really do.

Try
  • apply TFM
  • apply MCTemporalDenoise with preset "very high"
  • apply RemoveDirtMC
  • apply LumaSharpen with Strength 1.5, Pattern: Pyramid shaped
  • apply Toon
If the problem is just the intro you might want to restrict those filter so just the intro.
This is by no means perfect, but trying to fix this does not seem worth the effort.

Cu Selur
Since this source seems difficult to restore properly, I can also provide another source of the same content. It may be cleaner and easier to process, although it appears to have its own issues, including an unusual frame rate that I'm not entirely sure how to handle. 

Sample:  http://titant.free.fr/tmp/LH01b.mkv
something is wrong with the link
For that the input frame rate should be 29.970029 (Filtering->Misc->Overwrite Input->Frame rate) and the content is telecined (Overwrite scan type).
Also, the chroma is shifted in the first scenes and not the second.
(ChromaShiftSP(clip, X=2.00, jeh=False) works fine, when it's shifted, so you should configure Hybrid only shift the chroma on the first scene

Cu Selur
Thanks a lot, my friend! Really appreciate it.
Small follow-up on the second sample. Smile

I just remembered, I made a port of Avisynths AutoChromaFix a while ago.
Which automatically adjusts chroma shifts, I did a with your second source and it worked fine.

So you could:
  • save https://pastebin.com/YtP0mP0R as autoChromaFix.py into your 'Hybrid/64bit/vsscripts'-folder
  • load your second source in Hybrid
  • overwrite the input frame rate to 29.970029 (Filtering->Misc->Overwrite Input->Frame rate)
  • overwrite the content scan typt to 'telecine' (Filtering->(De-)Interlace/Telecine->Overwrite scan type)
  • Create a custom section behind the deinterlacer, by using 'Filtering->Vapoursynth->Custom->Insert before->ReplaceBlackFrame' and adding
    Code:
    import autoChromaFix clip = autoChromaFix.AutoChromaFix(clip, nodisplay=True)
    inside the text field.
This way the first scenes:
[Image: grafik.png]
and the second scenes:
[Image: grafik.png]
chroma are fine, without having to adjust the chroma shift per scene. Smile
General cleaning of the source shouldn't be an issue: https://www.mediafire.com/file/a5hqjjwdx...d.mp4/file

Cu Selur
Too late, I've already encoded everything. Undecided