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  1. Member
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    I have a 29.97 XVID clip, that has suffered from blending. I'm wondering if it's possible to convert it to FILM for better compression, if nothing else, when transcoding to DVD? I tried to read up on Restore24, but haven't been quite figure it out.

    I don't know if the source was FILM or PAL.

    Thanks in advance for any help.
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  2. Hi-

    If the height is anything other than 480, then it's been resized vertically, and it's too late to unblend it, using Restore24 or any other unblender. If it's, for example, 640x480, or 854x480, then there's hope.

    The source would have been NTSC.
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  3. Member
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    It has been resized vertically. No hope, huh? Oh, well.

    But in general, what you are saying is that if the source has not been resized, then it is possible to unblend? Do you by any chance have an .avs temlate for that sort of thing?
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  4. Originally Posted by manono
    If the height is anything other than 480, then it's been resized vertically, and it's too late to unblend it, using Restore24 or any other unblender.
    Why? I haven't seen Restore24, but if the source was blend deinterlaced and then resized there's logically no difference between the original size and resized versions except the dimensions. If there's something about Restore24 that requires 480 scanlines then you could just AddBorders() or resize back up to 480 lines.
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  5. Hi-

    You're making me think, and where I am, it's too early in the morning for that. Assuming this isn't a bad standards conversion, like PAL2NTSC, and mk2006's talking about a blend deinterlaced hard telecined 29.97fps source, then if it's the same height as originally, FixBlendIVTC was developed for this kind of thing and is what I was thinking of when I wrote my first reply. But thinking some more, it may work even on resized stuff. So I guess that's a good point, jagabo and thanks for the correction. I should say that I haven't tried it myself, but from reading about it, I think it should work. Here's the FixBlendIVTC thread:

    http://forum.doom9.org/showthread.php?t=101477&highlight=FixBlendIVTC

    From some info found in the function itself:
    FixBlendIVTC is a blend replacing / frame restoring function for doubleblends, caused by blenddeinterlacing of telecined sources. It will only work for this special case and is not created for any other conversions. Use import("FixBlendIVTC.avs") in your script and load the necessary filters to be able using this function.
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  6. Member
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    When you resize a blended video, you spread out the blend over more than one scan line making mostly impossible to recover the original video.

    But your title says that the original was 29.97p. If it really was a 29.97 source (interlaced?), then you should not try to convert it to 24p.
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  7. Member Alex_ander's Avatar
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    Much depends on the source origin and the history of its processing. There can be at least 5 cases.

    1. The source is a properly telecined film, it wasn't deinterlaced and wasn't resized vertically while compessing to xvid. There are chances to restore original frames by IVTC.

    2.Telecined but vertically a)resized up, b)resized down or c)cropped+resized (e.g. from letterboxed)
    a) some chances to resize back (reduce) and IVTC,
    b) no chances due to blending all fields (as said above, a line can't be narrower 1 pixel)
    c) problem with unknown cropped lines number

    3. The source is a result of conversion from PAL. Depending on the conversion method, different tools for restoration can be found in some cases. I recently chanced to repair such an xvid (ex-MPEG2, original size) file from NTSC broadcast of Montreux' Jazz (shot in PAL of course). It had heavy interlacing artifacts and I first tried Decomb (Telecide, guide 3), it didn't give completely progressive frames. But when I applied RePAL, specially designed to reverse after PAL-NTSC conversion by a particular method, it worked and I got clean progressive frames at 24.975 (it's natural that PAL source was deinterlaced before framerate conversion).

    4.The source was first telecined then deinterlaced by blending fields. Film can't be restored completely.

    5.The source is originally 29.97: nothing to improve (maybe deinterlace for PC only).
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  8. Member
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    My guess is that my Xvid was ripped from a DVD without first doing an IVTC, deinterlaced and resized. I think this is what Alex_ander refers to as Case #4.

    I'll play with FixBlendIVTC to see if it makes an improvement.

    Thanks all.
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