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  1. Been trying to convert a true 24fps video, that shows as variable 29.970fps, with no luck for hours.
    1. Tried Hybrid. Everything seemed normal, the program automatically enabled IVTC, which changes the framerate to 24fps, even when deinterlacing is set to: None. But, when the file is exported, the colors are off, just as with any other SD encode using this software. ColorMatrix and TimeCube doesn't solve the color problem, it's still incorrect + the video becomes stuttery for some reason.
    2. Used AviSynth+ and VirtualDub with this command:

    SetFilterMTMode ("QTGMC", 2)
    FFMPEGSource2("cut.mkv")
    AssumeTFF()
    LoadDll("..\fftw-3.3.5-dll64\fftw3.dll")
    Blur(0, 1.0).Sharpen(0, 1.0)


    I don't want to use QTGMC in that command, I just need the command to combine both fields, but without it the code just doesn't work. Is there a command that could replace it?


    But after exporting the Virtualdub file, it's completely out of sync with audio. Mediainfo shows a proper 24fps framerate, but the video is a few seconds longer, and not even audio delay can fix it, or changing the video speed to 23.976 or 29.970.

    3. Used HandBrake. But, again a dumb problem showed up. Constant framerate makes the video stutter, no matter the framerate set. Variable fixes it, but it creates a weird 24.*** rate, and I just want a stable 24fps video.

    It's almost 4am and my head hurts from reading info on plugins, color matrixes and whatnot. If Avisynth wouldn't've broken the sync, it would be amazing. Is there anything to fix it? I'm completely out of ideas now.
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  2. Member
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    Assuming you have the DVD ripped to your HDD along with the associated IFO files, etc,
    give VidCoder a go
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  3. This works and colors are all good, but now I'm realizing that the regular HandBrake is working as well for some reason. Something was glitched, or I did something wrong the first time, even though I remember selecting the same settings. Either way sorry for my mistake and thanks for recommending the program, it seems useful!
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    FYI, Vidcoder is based on Handbrake,
    some find it easier to use
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  5. Realized that, as it seemed to have the same settings as handbrake. But interestingly this also shows the real framerate of the video. I thought the vid was 24fps because MediaInfo showed that, when in reality it's 23.976. At least now it doesn't have a small frame freeze at one place like with 24fps.
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  6. Originally Posted by Hajker View Post
    SetFilterMTMode ("QTGMC", 2)
    FFMPEGSource2("cut.mkv")
    AssumeTFF()
    LoadDll("..\fftw-3.3.5-dll64\fftw3.dll")
    Blur(0, 1.0).Sharpen(0, 1.0)
    First, with mixed hard and soft telecine you should use rffmode=1: FFMPEGSource2("cut.mkv", rffmode=1).

    Second you shouldn't use FFMPEGSource2() at all for MPEG 2 video. Demux the MPEG 2 video to an MPG, M2V, or VOB file and use DgIndex to build an index file (with Honor Pulldown Flags mode) then use Mpeg2Source() to open the video via the index file.

    Third, bluring the two fields is a bad way of deinterlacing. Use TFM() and TDecimate() to field match and remove duplicate frames. That will leave you with a 23.976 fps video which will match the original audio.

    Unless your video has other problems. Post a sample of the source. Use DgIndex, mark a section, export with File -> Save Project and Demux Video. Upload the resulting M2V file.
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  7. Tried Hybrid. Everything seemed normal, the program automatically enabled IVTC, which changes the framerate to 24fps, even when deinterlacing is set to: None. But, when the file is exported, the colors are off, just as with any other SD encode using this software.
    Wild guess: source isn't properly flagged, Hybrid guesses the input color matrix wrong, thus sets the color output matrix wrong.
    If you change the color matrix, you also need to make sure the output color matrix is set properly.
    Also, Hybrid will apply deinterlacing&ivtc if the source is not progressive, but the output is.

    Cu Selur
    users currently on my ignore list: deadrats, Stears555
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  8. Originally Posted by jagabo View Post
    First, with mixed hard and soft telecine you should use rffmode=1: FFMPEGSource2("cut.mkv", rffmode=1).

    Second you shouldn't use FFMPEGSource2() at all for MPEG 2 video. Demux the MPEG 2 video to an MPG, M2V, or VOB file and use DgIndex to build an index file (with Honor Pulldown Flags mode) then use Mpeg2Source() to open the video via the index file.

    Third, bluring the two fields is a bad way of deinterlacing. Use TFM() and TDecimate() to field match and remove duplicate frames. That will leave you with a 23.976 fps video which will match the original audio.

    Unless your video has other problems. Post a sample of the source. Use DgIndex, mark a section, export with File -> Save Project and Demux Video. Upload the resulting M2V file.
    The video isn't telecined, it's just a telecine flag. Rendering the vid in HandBrake while deinterlacer is disabled all together renders out the video perfectly. But I'll keep this in mind for other stuff!


    Originally Posted by Selur View Post
    Wild guess: source isn't properly flagged, Hybrid guesses the input color matrix wrong, thus sets the color output matrix wrong.
    If you change the color matrix, you also need to make sure the output color matrix is set properly.
    Also, Hybrid will apply deinterlacing&ivtc if the source is not progressive, but the output is.

    Cu Selur
    I've never able to find the option to change the input color matrix manually. Is there a way to do so? Interestingly this is the only program that assumes rec709 for SD videos.
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  9. Interestingly this is the only program that assumes rec709 for SD videos.
    only on specific formats.
    iirc. Hybrid would only assume bt.709 if the source is MPEG-2 and has no flag.
    That assumption was rooted in https://forum.doom9.org/showthread.php?t=131571

    I've never able to find the option to change the input color matrix manually.
    don't think there is one, since I never had any need for it
    (I'll add an option for it in the next version.)

    Cu Selur
    Last edited by Selur; 26th Jan 2023 at 11:43.
    users currently on my ignore list: deadrats, Stears555
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    Originally Posted by Selur View Post
    Interestingly this is the only program that assumes rec709 for SD videos.
    only on specific formats.
    iirc. Hybrid would only assume bt.709 if the source is MPEG-2 and has no flag.
    That assumption was rooted in https://forum.doom9.org/showthread.php?t=131571
    This is the first time I see a case where for MPEG2 the program assigns BT709. VDub and MPC-HC assign BT.601 (AFAIK).
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  11. You can also make your life easier.
    Use clever FFmpeg-GUI, load your 29.97 fps Video, click main, click encode Video Stream, click keep resolution (in case you want mantain it), set the IVTC Box, you'll see the fps field is changed to 23.976, click encode. Done.

    Image
    [Attachment 68908 - Click to enlarge]


    You'll find your new 23.976 fps progressive Video into the target folder.
    If your source file is interlaced, yadif deinterlacing is applied. The colorspace is not changed.
    Last edited by ProWo; 27th Jan 2023 at 10:37.
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