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  1. Hey all,

    I've done quite a bit of reading but my brain is struggling. I think quite a bit because lots of people are talking about NTSC DVDs of these TV shows.

    For most of the time I'm reviewing my G1 Transformers and Thundercats DVD rips (MakeMKV) it feels like there is no pattern to the combs, certainly not a regular pattern 3:2 2:3 or whatever.

    I get this feeling that my PAL DVDs of these has been created straight from NTSC versions?

    It seems the source originally is film 24 full frames a second. Then it's been moved to NTSC at 60 half fields a second. (so 24 > 30 and then shuffled together where needed.

    Is it likely that what I have, and why it's looking so funky, is because that 30 interleaved frames off an NTSC disc have been put back to 25 frames?

    It seems avisynth is the way to go, but I just want to make sure that this kind of footage is recoverable to an ok standard first. Has anyone else had success getting PAL DVDs of these shows into some nice 24/25p footage without all the jagged bits?

    Thanks for any help.
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  2. Member
    Join Date
    May 2005
    Australia-PAL Land
    Search Comp PM
    Attach a sample of say 60 seconds or so, preferably with some movement in it. You can chop out a bit with AVIDemux: open the file in it, set the start point with the A button, set the end point with the B button, leave everything else as-is, and hit Save. That'll give us an un-recoded snip to analyse (not me, the experts! ).

    You can either attach it here or put on a file-sharing site.
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  3. I'll post up some clips shortly.

    I've been setting up avisynth along with some batch files for mass-processing.

    I've finished ripping all the ThunderCats DVDs and noticed some trends in the files.

    I think broadly what I'm seeing is just phase-shifted fields, and so far, for that footage, AviSynth and TFM without any decimation (so 25i to 25p) is working better than anything else... though I've noticed to review footage properly VLC is a nightmare of skipping frames etc... in one case I was going frame by frame and noticing repeat frames, but only when accompanied with an AAC audio stream... hard when you're checking exactly for frame repeats/drops... so I've had to dust off ffplay again to properly review what's going on (inc with colours!)
    Handbrake wasn't great, and ffmpegs tools not so user friendly on the way it'd find matching fields.

    The problem with animation is that it's already variable frame-rate in terms of the content on screen that was put to film at 24fps, so at some point the odd frame has been inserted to get it to 25p, or 30p a bunch of frames... but which ones are the interlopers?

    Also when motion is low, these phase-shifted fields are hard to see underneath the encoding noise, so you may be unable to determine what you're actually seeing.

    I've also noticed one episode in cursory checking that appears to have progressive frames except in one scene where it goes phase-shifted. It'll be interesting to see if TFM can work it's way through progressive frames without generating degradation, and then deal with the phase-shifted stuff.

    I can't understand the reason any phase-shifting mastering occurs. If you're putting it out to a 50i device you're just going to get the same result but 1/50th sec offset visuals.
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  4. Member
    Join Date
    Aug 2017
    United States
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    I don't know about Thundercats, but the Rhino (and then Shout Factory) DVDs of Transformers have a problem with '00s encoding artifacts.

    One, there is interlaced chroma interspersed throughout the whole thing. Leftovers of the prior image's color gets transferred to the next frame.

    Two, during the season 2 episode The God Gambit there begins a problem that continues through the rest of the series that I call "micro-interlacing". I think it's an artifact from early denoising efforts where any consistent horizontal movement results in leftover combing.

    In any case, the series is not too difficult to inverse telecine, the artifacts not withstanding. mode=4 in TFM will work.
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