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  1. Member
    Join Date: Dec 2008
    Location: United States
    Search Comp PM
    I have some MPG files that I want to convert into a DVD for viewing and group them on a DVD by chapters/MPG.
    The MPGs play fine in the computer, but when I demux them into a .m1k file and then extract the audio to .ac3, the m1k file loses around 15-20seconds of video(the video speeds up or is skipping frames or something).
    MPG file is 1hour 48sec, M1k file is 1hour 28sec

    I play the m1k file(video only, no audio) next to the original MPG and the m1k file over the course of the video will slowly pass and finish before the the MPG file. The audio's time is the same as the original MPG, so this means that the video gets ahead of the audio. I've been looking around, but haven't found anything so far to correct this issue or I'm simply not smart enough to figure it out. I opened the ac3 files and the mpg files in GSpot and they are CBR, but the MPG files say VBR in the container information.

    They are all MPEG-1 video 1150kbps, MPEG-1 Layer 2 Audio 224kbs 44100Hz CBR, System Bitrate 1412kbs VBR

    Any help would be appreciated. If I posted in the wrong forum, I am sorry. It's probably something simple I'm not doing.
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  2. hi and welcome to the vh forums!

    when you demux something it means to separate the the video from the audio. so if you had de-muxed the mpg. the video file wouldn't have any audio at all.

    what you are starting with is a vcd. mpeg1 video with mpeg2 audio, no ac-3.

    it's not really up to dvd quality, but if you look through the guides for a vcd to dvd guide and foolow it you should be able to put them on dvd.
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  3. Member AlanHK's Avatar
    Join Date: Apr 2006
    Location: Hong Kong
    Search Comp PM
    SVCD2DVDMPG (free version) does it: demuxes video, resamples audio to 48k MP2.
    You can author this using GuiforDVDAuthor.
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  4. Member
    Join Date: Dec 2008
    Location: United States
    Search Comp PM
    I can put them on DVD....
    It just comes out as having:

    1hour 48sec audio
    1hour 28sec video

    or a similar mismatch.

    The DvD plays fine, just it starts to go out of sync as the video plays, and the video runs ahead of the audio.
    I traced this back by watching each portion of the video I could during the whole process of making it to dvd.
    It starts doing this at the demuxing point.

    I demux it, then use an audio extractor to get the audio out into ac3 format, since my demux-utility apparently doesn't make audio streams or I just can't locate them. Then I author the video and audio with DVDAuthorGUI

    *edit*
    SVCD2DVDMPG acts like its working and demuxes the video, after this it pops up a screen that says:
    Filename is a layer II Stereo MPEG-1 audio stream without checksums.
    The sample frequency is 44.1kHz at a bitrate of 224 kbit/s

    At that point CPU usage goes to 100% and stays that way. I've let it sit there for an hour so far, and nothing happens.
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  5. Member AlanHK's Avatar
    Join Date: Apr 2006
    Location: Hong Kong
    Search Comp PM
    Originally Posted by VJep
    SVCD2DVDMPG acts like its working and demuxes the video, after this it pops up a screen that says:
    Filename is a layer II Stereo MPEG-1 audio stream without checksums.
    The sample frequency is 44.1kHz at a bitrate of 224 kbit/s

    At that point CPU usage goes to 100% and stays that way. I've let it sit there for an hour so far, and nothing happens.
    This is simply a shell for a number of command line programs you will find in the folder you installed SVCD2DVDMPG. You should see each open a command window as it operates.

    The steps are:
    1) demux with mpgtx, create a M1V and MP2 (seems OK for you)
    2) convert the MP2 to WAVE with maplay (seems to be where you're stuck)
    3) resample the wave at 48k to a new wave with ssrc
    4) convert the WAVE to new MP2 with mp2enc

    This should be very quick. Less than 5 minutes to convert a 30 minute video.
    If not...?
    Do you have enough disk space in the working directory? The wave files will be a few hundred MB at least.

    Otherwise, if you can demux the original MPEG, you can resample the MP2 with, say, BeSweet.
    Another way is to use TMPGEnc -- it will do operations on MPEG1 in demo mode.
    Open your MPEG, resave, changing the MPEG audio setting to 48000 sample rate.

    I don't know if this will solve your sync problem, but these methods have always worked for me.
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  6. Member
    Join Date: Dec 2008
    Location: United States
    Search Comp PM
    I'm not sure what was happening with it.
    Sometimes it would get stuck on maplay, sometimes it wouldn't.
    However i found that it was demuxing the videos correctly, which my old demuxer wasn't.
    I used my audio extractor to get the audio off the MPGs into the format needed, and now I've got them burned to DVD like I want them. It's not perfect quality since they were VCD MPGs, but it will do for what I need. Can't improve much on source?

    I have about 50 gigabytes on that drive left, and I'm not sure why it was giving random stops/freezes on maplay.exe.
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