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  1. Member
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    Sep 2001
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    Chattanooga, TN
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    I am ripping my DVD collection to mp4 and will be using Handbrake for converting. I started reading up on Handbrake's detelecine and decomb features and found out ways to tell if a DVD is hard telecined or not (or at least I think I have). So far I have ripped Indiana Jones and the ROTLA, Star Trek Nemesis, Fellowship of the Ring, and Quantum Leap episode. I dropped a VOB file from each one into VirtualDub and it says it is 29.97fps and when I step through it frame by frame I get the 1 progressive, 2 interlaced, 2 progressive pattern which from what I have read is hard telecined. I have also read that most DVDs should be 23.97fps and that the DVD player will take care of converting to 29.97fps. I am wondering if VirtualDub is being accurate because I find it odd that not only are Star Trek and FOTR are hard telecined, but that Quantum Leap which was a tv show has the same pattern and is not totally interlaced. I also decided to try a DVD of The Greatest American Hero which is older and it has the same pattern. Is there some flag VirtualDub is reading to cause this or are these really this way? Is there a better tool for seeing actual frames? When I use Handbrake to encode it always sees these as 23.97fps and regardless of checking detelecine or not will make the videos 23.97 because I am using same as source for fps. And after converting to mp4 and using the Quicktime plugin to read it into VirtualDub the 3:2 pattern is gone and it is a progressive 23.97fps video.

    My only other thought is that these are true 23.97fps with the repeat flag and VirtualDub is reading that flag. This is where I don't know what is really going on under the covers and can't make an accurate conclusion. This would make me curious about the TV shows being 23.97 though.

    Thanks
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  2. Is there a better tool for seeing actual frames?
    Open a VOB in DGindex. I'll assume these are only movies you'll be checking out. Run the Preview (File->Preview). In the Information window that opens up, if it shows as Progressive and Film it's soft telecine (progressive 23.976fps with 3:2 pulldown). If it shows as Interlaced NTSC it's hard telecine (the already telecined content encoded as interlaced 29.97fps. True interlaced video will show as the same thing. And so will PAL2NTSC field-blended garbage, but this will work for major American films and TV shows shot on film on NTSC DVDs.

    The default setting for VDub shows the interlaced 29.97fps output, no matter how it was encoded. There's a way to adjust it but, as I don't use VDub, I wouldn't know how to change the default behavior. If you look around, you should be able to find it. VDubMod ignores the flags so progressively encoded movies will show as progressive 23.976, with no interlacing. Hard telecine will show that 3 2 3 2 pattern of which you spoke.
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  3. Member
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    Thanks for the comments. I was using both movies and TV shows from DVD. That is what was confusing because both showed the 3:2 pattern and the TV shows were not interlaced. I dropped the TV shows into DGindex and it shows as 29.97 Film Progressive. Given that The Greatest American Hero came out way before DVDs and flat panel TVs I would think it would be interlaced and no conversion needed.

    This is still confusing to me, but it seems even the TV shows I tested are same format as movie DVDs.
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  4. Originally Posted by gminnick
    I dropped the TV shows into DGindex and it shows as 29.97 Film Progressive.
    It shows as 29.97fps only because Video->Field Operation->Honor Pulldown Flags is the default. If you were to change the Field Operation to Force Film (as you should when making a D2V project file for soft telecined sources), it'll show as 23.976fps.

    Another way to check is to open a VOB in GSpot. If it shows Pics/s as 23.976, Frames/s as 29.97, and Fields/s as 59.94, then it's soft telecine. If it shows Pics/s as 29.97, then it's hard telecine (or true video).
    but it seems even the TV shows I tested are same format as movie DVDs.
    Yes, many, if not most, TV shows these days are also shot on film. Some wind up on DVD as soft telecine; others are edited as video and hard telecined for DVD.
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  5. And then how do you handle Soft telecine vs hard telecine?
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  6. Originally Posted by siocnarf View Post
    And then how do you handle Soft telecine vs hard telecine?
    That's a little bit vague, but I'll assume you're reencoding the DVD and are using DGIndex and AviSynth.

    If so, the answer is easy. For soft telecine make the D2V project file using 'Forced Film' and you'll have a progressive 23.976fps D2V ready for your AviSynth script. If hard telecined make the D2V project file using 'Honor Pulldown Flags'. That will give you an interlaced 29.97fps D2V ready to IVTC within your AviSynth script. After the IVTC it'll be progressive 23.976fps.
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