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  1. I have some videos, which seems to be that someone who converted these videos from interlaced ones to progressive, forgot to add deinterlacing into a process.
    As result now video is progressive, but "lines" in motion are still present.
    There are similar topic, and no simple solution in every situation.
    Video has no/minimal artifacts when player window is downscaling movie, but when its 1:1 - issues are eye catching.
    Files are NSFW, and I made SFW 5 seconds sample, to represent problem.
    Here is comparison - https://i.imgur.com/ptWAEow.png both files are stored on different sites, and you can see that an approach in converting them is different.

    So what I'm asking for, what are main steps would be, to re-encode video and get rid of interlaced video artifacts? (If it's possible)
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  2. In the top image the interlaced video was scaled without consideration of the interlacing. The two fields can no longer be cleanly separated. About the best you can do is blur them together to look like the bottom image.
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  3. Originally Posted by jagabo View Post
    In the top image the interlaced video was scaled without consideration of the interlacing. The two fields can no longer be cleanly separated. About the best you can do is blur them together to look like the bottom image.
    Bottom image has totally fine quality for me. So, maybe you can give some advice where to start/what software is appropriate and will do the job.
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  4. Reduce the frame size to half height, back to full height, then add a slight vertical sharpen. Just the top half of the image:

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    I did that with AviSynth:

    Code:
    BilinearResize(width, height/2) # half height
    Spline36Resize(width, height*2) # back to full height
    Sharpen(0.0, 0.7) # restore some sharpness, only in the vertical direction
    But pretty much every video editor has resize and sharpen filters. You can get smoother results by adding an antialiasing filter while the video is downscaled. Adding Santiag() between BilinearResize() and Spline36Resize() gives:

    Click image for larger version

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    Depending on the video, you may have to use a smaller or larger size for the downscaled frame. And different scaling filters deliver different sharpness (bilinear is rather blurry, spline36 is pretty sharp),
    Last edited by jagabo; 18th Jul 2018 at 11:34.
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  5. Tried virtualdub, resize precise-bicubic 50% + resize 200% + some sharpen, and result is "okay" but for now I don't know for sure, if I like it.
    At the moment, I don't want to install some BIG video editors like PremierePro,... I will try to get decent quality with available software, like VirtualDub/Avidemux.
    Last edited by TempUser_; 18th Jul 2018 at 12:51.
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