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  1. Member spiritgumm's Avatar
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    trying to convert Pal-to-Ntsc in Avisynth. Have a Pal dvd with bonus videos (interview, trailer) which I thought were interlaced Pal so I used the usual script to convert to interlaced Ntsc (and encoded with HCenc as interlaced). However, the results had noticeable combing. I'm wondering if the video isnt interlaced, and/or what I'm doing wrong. Sorry this sample doesnt have alot of action.
    sample extra.m2v

    Here's the "typical" script, and if there's suggestions for changes, I dont care if it's interlaced, or slowed down to 23.976 with pulldown.

    AssumeTFF
    Yadif(mode=1, order=1)
    ChangeFPS(59.94)
    AssumeTFF()
    SeparateFields()
    SelectEvery(4,0,3)
    Weave()
    Image Attached Files
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  2. It' supposed to have combing. You're going from 25i it 30i.
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  3. Member edDV's Avatar
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    Use a deinterlacing player like VLC or MPCHC with YADIF enabled.
    Recommends: Kiva.org - Loans that change lives.
    http://www.kiva.org/about
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  4. By the way, you forgot to change the frame size.
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  5. Member spiritgumm's Avatar
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    When I watched it on TV, the combing during shot transition was terrible. It's much more evident in the trailer; I didnt provide a sample of that because I found a pre-exising NTSC trailer, and wont need to convert the Pal. The upload sample is of the original Pal interview bonus video.
    In regards to resizing, I didnt forget. I just didnt paste the entire script here - only what was relevant to frame rate changes. I also couldnt have encoded with HC if I did forget it.
    And as I am encoding to dvd video, PC media players are not applicable.
    Last edited by spiritgumm; 1st Aug 2011 at 22:39.
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  6. Originally Posted by spiritgumm View Post
    When I watched it on TV, the combing during shot transition was terrible.
    Then you didn't encode or author correctly. The AVS script should be encoded interlaced TFF. Make sure the authoring software correctly identifies the video as interlaced TFF.
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  7. Member spiritgumm's Avatar
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    still getting some combing (see attached image). comb.bmp
    I placed the resizing line "Spline36Resize(720,480)"at the bottom, right after Weave. Because this is interlaced, should I have placed it somewhere else?
    Image Attached Thumbnails Click image for larger version

Name:	comb.bmp
Views:	441
Size:	1,012.6 KB
ID:	8021  

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  8. It looks to me like you resized after interlacing. You should resize while the video is progressive. I'd do it right after Yadif().
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  9. Member spiritgumm's Avatar
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    have another interlaced 25 fps PAL - made for TV movie, from retail dvd I'd like to convert to Ntsc.
    I havent decided if it should be returned to film speed or left interlaced and weaved to 30 fps. Either way, the image doesnt look very good: after stepping thru the frames with Separatefields, I see the image moves up slightly every other frame, the result like aliasing. Since it's a regular pattern, is there a way to duplicate the good frame and delete the 2nd? You can see a black line on the bottom edge appear, disappear every other frame.
    sample.m2v
    Image Attached Files
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  10. It's actually 25p, field shifted

    mpeg2source
    assumetff
    separatefields
    trim(1,0)
    weave
    #resize
    #add whatever cleanup filters

    You can do the resize + PAL slowdown technique incl. audio, or keep audio and use dgpulldown technique

    You can add whatever filters you want, maybe cleanup the chroma noise a bit
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  11. That file is 25 fps encoded interlaced but contains progressive frames, with fields combined out of phase. In VirtualDub use the Field Delay filter. Or in AviSynth:

    AssumeTFF()
    SeparateFields()
    Trim(1,0)
    Weave()
    After that you'll have 25p.
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  12. Member spiritgumm's Avatar
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    I wasnt 100% sure, but there was so much combing, and the frames jitterbugged in Separatefields (with AssumeBFF) that I figured it was interlaced.
    But I'd really like advice about getting the frames of each field to be identical to eliminate the slight bouncing and pseudo-aliasing(whatever). If you step thru, you can see the frames dont quite match.
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  13. We both gave you fixes. Did you even try them?

    SeparateFields() always results in up/down bouncing. The lower field is separated and moved up to the same location as the top field. When the fields are woven back together it's location is restored.
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  14. You can also do a simple:

    TFM()

    Part of the TIVTC.
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  15. Yes, if the video switches back and forth between in and out of phase, TFM() will automatically adjust to the changes. Whereas SeparateFields().Trim(1,0).Weave() will fix the out of phase portions but make the in phase portions out of phase.
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  16. Member spiritgumm's Avatar
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    thanks, guys. Sounds like TFM will be a comprehensive fix. Looks good playing thru AvsP.

    I did try the phase fix in Avisynth which still showed the bouncing. When I play the retail dvd, there's alot of aliasing(?) which I thought was caused by the image bouncing, which is why I restated my issue. Also spent awhile looking online, and trying different plugins and scripts before initial posting.
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  17. There's no bounding after the script.

    AssumeTFF()
    SeparateFields()
    Trim(1,0)
    Weave()
    Image Attached Files
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  18. Member spiritgumm's Avatar
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    I was describing the "bounce" between frames when stepping thru Separatefields. I still see that in the script, but since you said that's normal, it was never the cause of aliasing. Looks like the phase fix addresses the aliasing (at least in AvsP).
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