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  1. Everything I say is false koberulz's Avatar
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    Code:
    General
    Format                                   : MPEG-4
    Format profile                           : Base Media
    Codec ID                                 : isom (isom/iso2/avc1/mp41)
    File size                                : 7.33 GiB
    Duration                                 : 3 h 59 min
    Overall bit rate mode                    : Variable
    Overall bit rate                         : 4 387 kb/s
    Tagged date                              : UTC 2018-11-26 13:49:55
    Writing application                      : Lavf56.19.101
    
    Video
    ID                                       : 1
    Format                                   : AVC
    Format/Info                              : Advanced Video Codec
    Format profile                           : High@L4
    Format settings, CABAC                   : Yes
    Format settings, ReFrames                : 3 frames
    Codec ID                                 : avc1
    Codec ID/Info                            : Advanced Video Coding
    Duration                                 : 3 h 59 min
    Bit rate mode                            : Variable
    Bit rate                                 : 4 284 kb/s
    Maximum bit rate                         : 5 500 kb/s
    Width                                    : 1 280 pixels
    Height                                   : 720 pixels
    Display aspect ratio                     : 16:9
    Frame rate mode                          : Variable
    Frame rate                               : 29.772 FPS
    Minimum frame rate                       : 14.983 FPS
    Maximum frame rate                       : 29.970 FPS
    Original frame rate                      : 29.970 (30000/1001) FPS
    Color space                              : YUV
    Chroma subsampling                       : 4:2:0
    Bit depth                                : 8 bits
    Scan type                                : Progressive
    Bits/(Pixel*Frame)                       : 0.156
    Stream size                              : 7.15 GiB (98%)
    
    Audio
    ID                                       : 2
    Format                                   : AAC
    Format/Info                              : Advanced Audio Codec
    Format profile                           : LC
    Codec ID                                 : 40
    Duration                                 : 3 h 59 min
    Bit rate mode                            : Variable
    Bit rate                                 : 92.8 kb/s
    Maximum bit rate                         : 99.8 kb/s
    Channel(s)                               : 2 channels
    Channel positions                        : Front: L R
    Sampling rate                            : 48.0 kHz
    Frame rate                               : 46.875 FPS (1024 spf)
    Compression mode                         : Lossy
    Stream size                              : 159 MiB (2%)
    Default                                  : Yes
    Alternate group                          : 1
    
    Text
    ID                                       : 1-CC1
    Format                                   : EIA-608
    Muxing mode                              : SCTE 128 / DTVCC Transport
    Muxing mode, more info                   : Muxed in Video #1
    Duration                                 : 3 h 59 min
    Bit rate mode                            : Constant
    Stream size                              : 0.00 Byte (0%)
    Encoded stream size                      : 0.00 Byte (0%)
    CaptionServiceName                       : CC1
    I have other identical files, which all work fine. This one drifts, with the audio finishing a couple of minutes before the video in Audacity, Audition, and Premiere. Plays fine and in-sync in VLC and PowerDVD.
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  2. Frame rate mode : Variable
    Frame rate : 29.772 FPS
    Minimum frame rate : 14.983 FPS
    Maximum frame rate : 29.970 FPS
    Original frame rate : 29.970 (30000/1001) FPS
    Look up "VFR" . Variable frame rate. It's discussed often

    Basically you'd have to convert to CFR to edit it.

    You're missing video frames. Video is shorter than audio , this causes the drift. In a media player, timecodes keep it in sync by displaying certain frames longer than usual. In a CFR version, there would be duplicate "placeholder" frames instead at those spots
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  3. Everything I say is false koberulz's Avatar
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    WTF? All the others are CFR, I have no idea why this one is VFR.

    *sigh*
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  4. Everything I say is false koberulz's Avatar
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    Okay, looks like one other is also VFR, but it works fine in PP. Weird.

    How do I convert this one so it co-operates?

    Also I'm not sure I am missing video frames, as the audio always finishes early which implies added frames, not absent ones does it not?
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  5. Originally Posted by koberulz View Post
    Okay, looks like one other is also VFR, but it works fine in PP. Weird.

    How do I convert this one so it co-operates?

    Also I'm not sure I am missing video frames, as the audio always finishes early which implies added frames, not absent ones does it not?




    If it's minimally variable, or just minor jitter in the timecodes, then you might not detect a sync issue . These aren't truly VFR, and can be treated as CFR. You might be able to remux it and fix those

    Ones that have larger variations, will produce a sync issue for sure in PP or any editor

    Newer versions of PP handle VFR slightly better

    If the "assumed" CFR frame rate in PP is below the actual average framerate, the video might be longer. If the "assumed" CFR frame rate in PP is above, the video might be shorter. But it in both cases, they will still be in/out of sync in sections if you don't have one of the minimally variable cases

    You can do the math. Look at the framecount and calculate the duration based on a FPS. 99% of timecode VFR cases will have missing frames



    Use search, it's discussed often. Search for "VFR to CFR". There are several methods, several variations,none of them perfect, but it will be better than what you have now. For example, you can use avisynth to convert to CFR

    DirectShowSource("video.mp4", fps=29.97, convertfps=true)
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  6. Everything I say is false koberulz's Avatar
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    It's still out of sync after doing that.
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  7. Was the output file in sync in a media player? What format did you use, what does mediainfo say ?

    The minimally variable ones where you can just assume CFR, usually have min/max like 29.95, 29.98 or something (ie. very little deviation, just jitter). But you have min 14.983 . But it might work , you can use mp4fpsmod to patch it to CFR. But I doubt it will work for that one, because it really is variable
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  8. Everything I say is false koberulz's Avatar
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    I just told PP to interpret as 29.97 instead of 29.77, worked out how long that made it, reset it to original, and then used the rate stretch tool on the video. It's now synced at both ends, fingers crossed it's functional across the bit I need (which is only about 30-40 minutes of the four hours).
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