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  1. Member
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    I don't feel like nitpicking over terminology on this. Anyone able to answer my question here fully understands what I mean when I refer to the phenomenon of generating a full 60fps from what was originally "30 fps" 1080i (or 480i). Digital TVs do it effortlessly, after all.

    Randomly decided to investigate which player, between VLC and MPV, offers a better result from its efforts to deinterlace 1080i video. But I didn't expect to learn that neither of them are capable of producing 60fps from 1080i input. While they do deinterlace, they do not restore the temporal resolution of the 60 fields per second locked away in the 1080i video -- both of them display 30fps only. (For what it's worth, VLC's best result looks like Yadif 2x, and MPV's sole deinterlacing process seems to be the same thing. Neither result looks as good as what you get from a typical modern HDTV, though this is without question due to the fact that modern TVs don't have trouble faithfully outputting 60fps, rather than any shortcoming in the algorithm.)

    I feel like I keep coming back to deinterlacing problems every year or so. I once tried finding a player that could do vector adaptive deinterlacing, but that was a failure. Now I'll settle for just the garden variety result I'd get out of a cheap TV.
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  2. VLC Yadif 2x does 1080i30 to 1080p60. I haven't tested but I'm sure mpv can do that as well.

    Are you sure you are asking for deinterlacing and not some kind of frame interpolation (for e.g. 1080p30 to 1080p60)? Are your sources truly interlaced?
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    Originally Posted by sneaker View Post
    VLC Yadif 2x does 1080i30 to 1080p60.
    Not for me. It produces 30fps, and the elements in the 1080i30 video that had obvious weave end up having a snaking blend effect instead.

    For what it's worth, Yadif / Yadif 2x does seem to handle 480i correctly.

    Originally Posted by sneaker View Post
    Are your sources truly interlaced?
    They are. However, it is entirely possible that they are something silly like bottom field first (though in that case I would expect to see a completely different issue). I feel that if the job of Yadif is to output 60fps, rather than detect a valid video stream, it wouldn't be giving me 30fps as output regardless. At this point, I'm uncertain where I should place my suspicions.

    If you're interested, the test sample I've been trying to view deinterlaced is the first 3/4ths of this:

    https://www.youtube.com/watch?v=s4uwDrdLfS4

    Edit: Example of a piece of a frame, interlaced original followed by Yadif 2x.




    Rather than creating individual frames from the two weaved fields, Yadif 2x is simply blending the two together in a strange way, as made evident by the double contouring along the shark's edges where weaving used to be.
    Last edited by Asterra; 10th Mar 2019 at 04:55.
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  4. I think that sample is already b0rked, not truly interlaced anymore. Forget about youtube+interlacing.
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    Originally Posted by sneaker View Post
    I think that sample is already b0rked, not truly interlaced anymore. Forget about youtube+interlacing.
    Could be, yes. Then I suppose my remaining surprise is that Yadif flatly refuses to output 60fps if it isn't satisfied that the video it's dealing with is interlaced. (And that's when I manually tell VLC to deinterlace the darn thing.) If I fed the same thing to a TV, I'd get my 60fps, b0rked or not.
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  6. VLC can play 1080i30 at 60p but it depends on the codec (and container?). Attached are two 1080i30 videos, one MPEG2 in MPG, the other AVC in MKV. VLC plays the first properly with Yadif2x (60 different picture per second) but not the second (only 30 different pictures per second). With Bob it plays both properly at 60p. Other players play both at 60p (depending on configuration) -- MPCHC, MPCBE, SMPLayer, PotPlayer... Behavior can also vary depending on graphic renderer chosen, and the graphics card and driver settings.
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  7. aBigMeanie aedipuss's Avatar
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    if an interlaced frame's fields(each of which only contain a 1/2 of the total vertical resolution) are just put back together, because the camera records only every other line every 60th of a second you get jagged edges on anything moving. no de-interlacer can ever be perfect putting back together what wasn't recorded together in the first place. interlacing was used to allow crt tvs to produce the best possible picture using very limited bandwidth.
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    "a lot of people are better dead" - prisoner KSC2-303
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  8. Mr. Computer Geek dannyboy48888's Avatar
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    Try mpc-hc. On my interlaced episodes of mythbusters etc it displays 59.94 fps during playback
    if all else fails read the manual
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