Diagonal Stripes After Deinterlacing in Hybrid QTGMC

[ValdiG]

Hello! My Hybrid version is 2025.03.09.1 running on Windows 10. I am working with a digitized VHS tape from 2002, which is an animated series from the same year. This tape was digitized as interlaced video; all media info will be placed below. As a perfectionist, I digitized it in Hybrid, using VapourSynth and QTGMC Placebo mode. Please see the attached screenshots that were taken from my completed deinterlaced video. I don't like the final result because, even after deinterlacing in Placebo mode, you can see these horrible diagonal stripes everywhere (faces of the characters, snow, sky, etc.). Please tell me how to get rid of them using Hybrid? What settings do I need for it? I asked ChatGPT this question, and it recommended this:

In Hybrid, set up QTGMC with stronger AA. Open Hybrid → Filtering → (De-)Interlace / Telecine → Deinterlace/Telecine Settings → Deinterlace 2. Choose QTGMC as your deinterlacer. 3. Click Configure next to QTGMC and adjust: Preset → Slower (or even Placebo if you have the time) TR2 → 2 (that boosts the temporal radius and smoothes aliased edges) Sharpness → around 0.4–0.6 (lowers ringing and helps edge anti-aliasing) EdiMode → 1 (EEDI3) for the best diagonal line reconstruction Leave Noise at 1 or 2 if your source is a little noisy (helps hide residual artifacts) Add a Deband (and/or mild temporal denoise) filter Right after your QTGMC step, do:

Filtering → Miscellaneous → Deband Radius: 16 Threshold: 4 (luma) / 4 (chroma) Sample: 4 Grain: 0–1 (to avoid flat, “plastic” surfaces)
(Optional) Filtering → Denoise → MCTemporalDenoise Sigma: ~1.5 Block: 4 This will slightly smooth any leftover high-frequency noise without blurring the picture. Encode & mux in one pass By keeping the entire pipeline in Hybrid—from interlaced source ➔ QTGMC ➔ Deband ➔ encode ➔ mux—you avoid any re-import/re-export steps that might re-alias the image.

But the problem is that I don't see these exact settings in my Hybrid version. Please tell me what to do.

Here is media info for my original interlaced video: Format: ProRes 422 HQ in a QuickTime MOV container • Resolution: 720x486 pixels • Aspect Ratio: 4:3 • Frame Rate: Listed as 59.940 FPS (100160000) • Scan Type: Interlaced • Scan Order: Top Field First • Bit Rate: 127 Mb/s • Bits/(Pixel*Frame): 6.053 • Duration: 23 minutes 40 seconds (1420 seconds) • File Size: 21.5 GiB • Color Space: YUV 4:2:2, BT.601 NTSC
[Attachment 86920 - Click to enlarge]
[Attachment 86921 - Click to enlarge]

[Selur]

Since Valdi also posted in my forum, I shared a rough suggestion there on how one might approach the issue: link.

[Alwyn]

That's an interesting one. Neat Video couldn't do much with it. Be interesting to see what the AVISynth gurus could make of it...

Here's the file:

https://mega.nz/file/zMVGibSA#EtTyNJ3fad1eJG8HvwgdkpUrNZdBDlHLAloaRSe-ARU

[Selur]

In Avisynth defreq should work if configured properly, also the filters I used in Vapoursynth also are available for Avisynth. (imho the main problem isn't with the frequency artifacts, but with the messed up deinterlacing)

[ValdiG]

Is the degreq filter already a part of the Hybrid version 2025.03.09.1 that I'm using, or should I install it separately?

[Selur]

Defreq is not part of Hybrid, in theory you could use it in a custom section, but it might not be easy to understand or use.
So if you want to use Hybrid, better use the steps I listed to create the script I used on your system.