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  1. Is there a way using avisynth or virtualdub to make a 29.97p to 29.97i? I really don't want to reduce the framerate to 23.976 and use 3:2 pulldown. I'm just trying to find another way to get progressive animations to dvd while keeping quality of motion and image.
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  2. Just encode them as interlaced MPEG2.
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  3. Originally Posted by jagabo
    Just encode them as interlaced MPEG2.
    I tried to set it to interlace both in HC and Procoder Express but final output is still progressive. I thought that option was for video that's already interlaced?
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  4. The frames will look almost the same (no comb artifacts). The difference is how the codec handles them internally.

    Think of it like this: the MPEG encoder can't know if the two fields in each frame come from the same picture or from different pictures. If you tell it the frames are from two different pictures (interlaced) then it handles them as such.
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  5. Always Watching guns1inger's Avatar
    Join Date: Apr 2004
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    A lot of PAL progressive source is encoded as 25i, with identical fields.
    Read my blog here.
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  6. Originally Posted by jagabo
    The frames will look almost the same (no comb artifacts).
    Ok, thanks.

    One more question. Then why when I open the M2P in VirtualDub MPEG2, it still has the same amount of frames? Does it just display like frame 1 twice?
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  7. Always Watching guns1inger's Avatar
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    Frame = 2 fields. Open it in g-spot 2.60b and look at the number of pics/second versus number frames/second
    Read my blog here.
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  8. Why would the frame count differ? It'll have the same frame count, and twice the number of fields, either way you encode it.

    If you're really concerned about motion fluidity, you'd have to go back and create it at 29.97fps interlaced, or 59.94 fields per second (each field being unique and different, rather than each field having a duplicate (sort of), as is the case now). However, since you seem to be pleased with what you have, encoding it as interlaced or progressive will pretty much amount to the same thing.
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  9. Member edDV's Avatar
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    Location: Northern California, USA
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    For "NTSC":
    29.97p shown as 29.97i will still have 29.97Hz motion resolution but has "refresh" scanning at 59.94Hz thereby reducing the TV flicker.

    23.976p is frame repeated 3:2 to get to 59.94Hz refresh. Motion resolution (smoothness) remains 23.976Hz.

    For "PAL":
    25p shown as 25i will still have 25Hz motion resolution but has "refresh" scanning at 50Hz thereby reducing the TV flicker.

    For Movie Theaters:
    24p film gets 2x(typ) frame repeated in the gate mechanism to get 48Hz refresh. Motion resolution (smoothness) remains 24Hz.

    The human eye sees considerable flicker at 30Hz and below. The eye adapts at 48-60Hz but some claim this results in "eye fatigue". Computer monitors usually refresh 72Hz to 100Hz. or more to give the eye that paperlike quality.

    For the eye, white surfaces show more flicker than dark surfaces. Computers use the white paper metaphor for display and hence show more natural flicker. TV sets and movies hide flicker by tending to the dark side
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  10. Ok, thanks alot guys. Just one more thing that manono mentioned. What if I make a 59.94p and then encode it at 29.97i. Is this the unique different fields you're talking about from above?
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  11. Nevermind, I think I know the answer to that.
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  12. If you render as 59.94p you will need to pull fields out of those frames to create 29.97i frames. This can be done with an AVISynth script but I don't know of any MPEG encoders that can do this.
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  13. Hi-

    What if I make a 59.94p and then encode it at 29.97i. Is this the unique different fields you're talking about from above?

    That's something slightly different, but it will work, if you then know how to get it back to 29.97fps interlaced (for DVD, right?). Here's where AviSynth comes to the rescue. If your program will only create 59.94p (59.94 frames per second), as opposed to 29.97i, to return it to 29.97fps interlaced:

    SeparateFields()
    SelectEvery(4,0,3)#if TFF, SelectEvery(4,1,2) if BFF
    Weave()#encode for TFF
    ConvertToYUY2(Interlaced=True)#if for CCE
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  14. Or:

    AssumeTFF() #or AssumeBFF
    SeparateFields()
    SelectEvery(4,0,3)
    Weave() #output will be TFF if AssumeTFF(), BFF if AssumeBFF()
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  15. Member edDV's Avatar
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    Originally Posted by J. Baker
    Ok, thanks alot guys. Just one more thing that manono mentioned. What if I make a 59.94p and then encode it at 29.97i. Is this the unique different fields you're talking about from above?
    Exactly !

    This what NTSC TV or 480i/1080i is all about. 59.94Hz. frames (natural motion) but shown as half line fields to conserve bandwidth. Motion resolution (smoothness) is still 59.94Hz but bandwidth is half. Downside is you see those pesky interlace lines during motion on a progressive display.

    For PAL, 576i is all about 50Hz. frames (natural motion) but shown as half line fields to conserve bandwidth. Motion resolution (smoothness) is still 50Hz but bandwidth is half. Downside is you see those pesky interlace lines during motion on a progressive display.
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  16. Originally Posted by manono
    Hi-

    What if I make a 59.94p and then encode it at 29.97i. Is this the unique different fields you're talking about from above?

    That's something slightly different, but it will work, if you then know how to get it back to 29.97fps interlaced (for DVD, right?). Here's where AviSynth comes to the rescue. If your program will only create 59.94p (59.94 frames per second), as opposed to 29.97i, to return it to 29.97fps interlaced:

    SeparateFields()
    SelectEvery(4,0,3)#if TFF, SelectEvery(4,1,2) if BFF
    Weave()#encode for TFF
    ConvertToYUY2(Interlaced=True)#if for CCE
    That's what I need. Thanks you.

    Oh, I use an animation program (AnimeStudio) that only exports to progressive. That's why I was looking for this information. Thank you guys again.
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  17. Member edDV's Avatar
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    Location: Northern California, USA
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    The animation industry has figured out all the cheats. The problem they face animation is "white paper" based (native flickery) but they need to be clever about cell rate (motion).

    I can't recall exactly how they optimized the animie solution but they spent a lot of time figuring it out.

    I recall the width of the black outlines being one of the solutions for interlace video.
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  18. I'm still trying to learn it all myself. Seems like once you learn one thing, either something new comes along or someone else has another way. I guess it keeps it interesting.
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