Advice for VHS video (Jagged edges)

Hi,
What would be the best settings to clean up the (possible) deinterlace jagged lines in the video. I have tried the deinterlace modes, shrinking the video. I am out of ideas to fix

I do not have the original video only post processed.

Gaia HQ maybe

The problem is that the video has been converted and resized by some method that didn’t deinterlace in any kind of sympathetic way. I’m guessing it began life as a PAL 4:3 Mpeg 2 interlaced and was converted at high speed into 1280 x 720 H264 progressive.

Topaz deinterlace modes are no good (for this) because you don’t have an interlaced source. You said you’ve tried shrinking the video. I assume you mean dropping bitrate and resolution so that the “jags and lines” are effectively blurred, and then resizing? This might help if the source was high quality and the artefacts minimal, but here you’re going to lose so much detail that it ends up worse - which I guess is what you found.

I think part of the problem is that the resizing to 1280 x 720 has been done by simply stretching a 4:3 original to fit, making the interlacing scan lines more obvious. I found a bilinear resize to 720 x 544 (to restore 4:3) helped a lot - apart from making everybody less dumpy. You can also use QTGMC, which is a deinterlacer, to reduce some of the fringing. It expects an interlaced input, but will work with progressive video with the appropriate settings. To be honest, I’m not convinced it helped much here.
Here’s the clip: https://youtu.be/N7wcd341jbg

I ran this through Topaz (Artemis medium quality 1080P MP4) : https://youtu.be/rdlJpX1z_7U
Unfortunately, along with the elements that are wanted, the interlacing artefacts are “enhanced” as well.

I’m not sure what you know/don’t know about using tools like Avisynth/Virtualdub etc so I haven’t gone into much detail, but if you need more I can point you in (hopefully) the right direction.

I’m not certain you’ll ever get rid of the artefacts without a great deal of work, if at all. I’ve seen people who know a great deal more than me working on similar problems, e.g. here https://forum.doom9.org/showthread.php?t=170813 (including the embedded links) and it looks to be a great deal of work.

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Thank you, That is a very in depth test. It does look slightly improved. I sincerely thank you for going through all the effort THANK YOU

I suspect with a bit of care, you could improve on that, maybe experimenting with different resize filters, bitrates etc. but I did this quickly without too much close attention. And you’re welcome - I was interested to see how it would look. Part of the problem is that the clip is almost designed to induce interlacing artefacts: loads of rapid movement, flashing lights etc.

Those are the cases where “not possible” comes closer :slight_smile: But to see what could be done, we would need an exact unaltered peace of the clip… Like mentioned above, resizing interlaced material as progressive in most cases destroys the chances of cleaning it up again afterwards. But to be sure - upload withoput recompressing your clip or a small snipplet of it.