How to get rid of these combing artefacts?

[8-BaLL]

Hello,

after Tdecimate(), which gets rid of telecining (from 29.97 fps to 23.976 fps), I end up with frames that have combing artefacts. It seems as if most likely interlaced VHS video was telecined without deinterlacing it first.

Here are a few examples of how it looks:

https://i.imgur.com/4Ic5KOE.png

https://i.imgur.com/ggxrATV.png

https://i.imgur.com/iOgcRZc.png


here is a short clip of the video:

https://mega.nz/file/Bs0D3YJD#1O6n9ZVZwYEEYd-RlSw8-Jp68Av8JJk7Zi2deRK41X8


I tried QTGMC and it removes some of those artefacts but not everything.

Any idea how to "fix" that? Source is original DVD.

[wonkey_monkey]

It'd be better to post non-upscaled images. It looks almost like dot crawl, but it's hard to tell whether that's because it is, or because of the upscaling.

[manono]

You can provide M2Vs cut from the VOB using DGIndex or other ways to provide a piece of the VOB file. You don't need to repackage as an MPG before packaging it yet again as an MKV. It requires an extra step for anyone willing to help. Also, post any script you've used.

It seems as if most likely interlaced VHS video was telecined without deinterlacing it first.
That's not how it works. The VHS tape would have already been telecined (if that's where it's from originally and if it was shot on film).

Those artifacts aren't from interlacing but are called 'dot crawl'. Except that last picture which looks to me as if it was resized before being made progressive. There are a number of dot crawl removal filters.

http://avisynth.nl/index.php/External_filters#Rainbow_.26_Dot_Crawl_Removal

In that sample, the part with J-Lo dancing is a mess and a lot of deinterlacing is required. To get better results you can switch from the default deinterlacer to using QTGMC for the job, something like this:

tdeintted = QTGMC(FPSDivisor=2)
tfm(clip2=tdeintted).tdecimate()

[johnmeyer]

Looks like either dot crawl or, more likely, the result of scaling interlaced video without first deinterlacing.