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  1. Member
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    I have a bunch of avi with 23.976 frame rate. I have encoded them in TMGPEnc with 23.976 and then 3:2 Pulldown to get them to the NTSC standard I need for putting them on DVD. I also just encoded them and left them at 23.976 and still get the jitters.

    Also when I watch the AVI on my computer I get the same jitters.. When I watch the avi on the computer is the computer trying to play it back at NTSC standard.

    My question is - Any ideas as to how to get the jiggering out?? I have about 40 avi that I need to encode so I am looking for a simple solution..

    thanks with any input -

    Mark
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  2. Always Watching guns1inger's Avatar
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    So you are saying that these jitters are already in the source avis before you encode them to DVD ?

    And these are 23.976 fps files ?
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    Originally Posted by guns1inger
    So you are saying that these jitters are already in the source avis before you encode them to DVD ?

    And these are 23.976 fps files ?
    Yes - they are 23.976 fps files avi...

    I have done a couple of different methods and still see them - I can really see them when it is panning in..

    Here is what I have done -

    23.976 to 23.976 fps with Pulldown
    23.976 to 23.976 fps
    23.976 to to 29 fps

    All seem to have the jitters..
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  4. Always Watching guns1inger's Avatar
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    I really don't understand what you ate trying to do, and I suspect that you don't either.

    The correct method for converting 23.976 fps AVI files to DVD is to encode them as 23.976 fps Mpeg-2 video, and then apply 23.976 fps -> 29.970 fps pulldown (also known as 2:3 or 3:2 pulldown).

    Pulldown from 23.976 to 23.976 does nothing, and isn't DVD compliant.

    Encoding 23.976 to 29.970 fps will introduce artifacts and jitters into the video because you are either inserting duplicate or blended frames inbto the video.

    If the source already has jitters then the problem is with the source, and converting to DVD is not going to fix it. You have to work out why you have jitters in the source, and whether or not that can be fixed.

    A short segment of the clip might help us diagnose where your issue. Post a section that clearly shows the problem.
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    Thanks for the response - sorry about not being clear..

    My main question is.. how do I tell if the jitters in in the avi - if it is encoded at 23.976 fps and I watch it on my computer should it NOT have the jitters - is my computer playing it at NTSC standard?? Or will a computer just play it at the rate that is was recorded?
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  6. Originally Posted by funkymix
    My main question is.. how do I tell if the jitters in in the avi - if it is encoded at 23.976 fps and I watch it on my computer should it NOT have the jitters?
    If it's 23.976fps but plays jerky, then I don't understand how you'd expect any conversion to DVD done using any method, not to also play jerky. How can you tell if it's not supposed to play jerky? Well, you can bet the original source didn't play jerky, so the obvious answer to that question is to tell you not to download garbage from the internet, but to convert to AVI from your own collection. In any event, if you were to upload a small sample of one of these source AVIs - one showing steady movement - we might be able to tell you what's wrong with it.

    Properly created AVIs don't play jerky on a computer. Most likely whatever's wrong with it has nothing to do with your player or the computer (unless the resolution is so high that your CPU can't decode it in real time).
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  7. Always Watching guns1inger's Avatar
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    FWIW, computers don't actually care about PAL or NTSC. They playback frames per second. If the video is 23.976 fps, then it will play back at 23.976 fps. If it is 12.5, it will play back at 12.5.

    Also, film is not completely jitter free when projected at 24 fps, which NTSC progressive is very close to. A sample will tell us if this is a bad encode, or if the original was like this.
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  8. Member
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    Originally Posted by guns1inger
    FWIW, computers don't actually care about PAL or NTSC. They playback frames per second. If the video is 23.976 fps, then it will play back at 23.976 fps. If it is 12.5, it will play back at 12.5.

    Also, film is not completely jitter free when projected at 24 fps, which NTSC progressive is very close to. A sample will tell us if this is a bad encode, or if the original was like this.
    Okay - how you you like me to send you a sample - yousendit??
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  9. Always Watching guns1inger's Avatar
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    If you can cut it down to 2 MB or so (and we shouldn't need more than that) then you can post it here as an attachment. Just use the Browse button under the field you type your replies into.
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