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[HELP] Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Printable Version

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Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Valdi - 09.05.2025

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:
  1. Filtering → Miscellaneous → Deband Radius: 16 Threshold: 4 (luma) / 4 (chroma) Sample: 4 Grain: 0–1 (to avoid flat, “plastic” surfaces)
  2. (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

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Selur - 09.05.2025

Those lines are not caused by the deinterlacing.
Would need a link to a small sample to look at to give any suggestions.

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Valdi - 09.05.2025

No problem. Please tell me, do you want to get a sample of the original interlaced video, or a deinterlaced video? This problem with diagonal stripes can be seen on both.

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Selur - 09.05.2025

Of the original please

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Valdi - 09.05.2025

I have uploaded a 15-second sample of the original interlaced video. Please take a look:
https://mega.nz/file/zMVGibSA#EtTyNJ3fad1eJG8HvwgdkpUrNZdBDlHLAloaRSe-ARU

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Selur - 09.05.2025

Downloading the file, will report back once the download is finished, and I had a look at it and can suggest something. Smile
What graphic card are you using?

Cu Selur

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Selur - 09.05.2025

When I look at the sample and overwrite the scan type to progressive, there are no combing artifacts.
(there is a lot of aliasing)
=> that file is not interlaced

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Valdi - 09.05.2025

Intel HD Graphics 5500

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Selur - 09.05.2025

Okay, so only conventional and not machine learning based filtering is needed. Smile

Cu Selur

RE: Diagonal Stripes After Deinterlacing in Hybrid QTGMC - Valdi - 09.05.2025

Please tell me how to get rid of these diagonal stripes using my current Hybrid version 2025.03.09? What settings do I need to apply?