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  1. Member
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    Jan 2004
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    I can see why... Huh??
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    I've got a VOB file created with MTR. I've demuxed it with bbDemux and MPEG Streamclip. Both apps give me an m2v file that Quicktime reports as 640x480, and each m2v in either case is rejected by DVD Studio Pro 1.5 as "bad format". If I export the m2v out of Quicktime to any format and then reencode it as 640x480, DVDSP flatly won't import it at all. If I reencode it as 720x480, DVDSP takes it as good, BUT it ends up being out of sync with the demuxed AC3 sound.

    So...

    I was under the impression that 640x480 was not a viable frame size for DVDs, that it had to be 720x480. If this is the case, why does demuxing the VOB give me an m2v that's the wrong size? And secondly, why would it be the wrong length? It ends up being short by about .1%, and MPEG Streamclip says there are no timecode breaks.
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  2. Member
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    If the files demuxed directly are rejected by DVDSP1.5 and they are otherwise in spec for DVD, chances are great the GOP length used in the file is > 15.

    My other thought is the frame rate is 24fps. Try to add flags so that DVDSP1.5 sees it as 29.97. Can someone help remind me the name of the software that adds pulldown flags?
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  3. Don't trust the resolutions QT Player reports for MPEG1/2 files!

    It automatically scales and reports NTSC 720x480 as 640x480 and PAL 720x576 as 720x540 in an attempt to mimic 4:3 resolution.

    BTW, the correct thing would be to scale 4:3 NTSC to 656x480 or PAL to 788x576 -- this would have the added benefit that it wouldn't ruin the interlacing pattern with PAL... 16:9 NTSC should be scaled to 875x480 and PAL to 1050x576.

    Anyway, check the correct resolution with MPEG Streamclip, for example.
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  4. Member Cornucopia's Avatar
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    For now, let's assume the Demux worked correctly (which might be some cause for the problem), and the VOB creation worked correctly (more possibilities for problems). Then that means that your file IS 720x480 and is just being incorrectly labelled in QT player.

    In any case, YOU SHOULD NOT RESIZE! (You shouldn't have to). And neither 640x480 nor any of those other quoted sizes are DVD-compliant.
    You obviously want to end up with a DVD, so don't take such a circuitous route. You'll just end up with worse quality.

    Your problem mainly seems to be frame rate. A .1% difference in length is the difference between a file reported as 30fps and one that is reported as 29.97fps (the correct rate).

    Sounds to me that maybe the GOP/MPEG headers are off and need to be repaired.

    Scott
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  5. Member
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    I can see why... Huh??
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    Sorry, I was mistaken in my original post. I demuxed the VOB with bbDemux, but not MPEG Streamclip. The VOB caused Streamclip to crash. The other app I used to demux it was MTR ("Title Only demux", straight from the disk, not the VOB). In either case, i ended up with an m2v with the symptoms I originally described. I guess that points to a problem with MTR.

    But regardless, how would I "repair headers"?
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  6. Member terryj's Avatar
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    The vob file that was ripped from MTR....was this
    a commercial disc you own, or a created disc?

    If it was a commercial disc, go back and try a re-rip at
    Full Disc mode. See it it prompts you for ArCCos...
    or insists it pad the VOBs due to Bad Sectors.
    ( always tell it to Pad, not Delete the Bad Sectors)

    If it does either one, then I would take the completed output
    over to MPEGStreamclip, and have it fix time
    code breaks first, then demux the vob.
    It should be fine then.

    If it is a created disc, then was it created on a DVR?
    If so then that opens up another whole set of problem.

    But try my first suggestion and see what happens.
    "Everyone has to learn, so that they can one day teach."
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