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  1. I'm having a very frustrating problem with one of my video files. I would like to convert it from mkv to mp4 but it loses audio syncronisation for mysterious reasons. I usually use mkvtoolnix to demux and yamb/mp4box to remux in mp4. I have tried many many builds of both and the resulting video always has sync problem. The sync problems persist even if I just try to remux the extracted streams into a new mkv (using mkvtoolnix for both demux and remux). After further analysis I think the problem lies in the fact that media info reports the initial mkv as having 131090 frames and once I demux the h264 video stream, whether I import it into an mkv or an mp4 it'll always report 131109 frames, with 19 added frames somehow. No version of mkvtoolnix that I have tried could demux that video stream to be 131090 frames. TSmuxer also demuxes it to be 131109 frames...
    Importing the original mkv into avidemux also shows that 131109 number of frames. Does someone know what is going on? Why is there a discrepancy in number of frames? Was the original h264 stream shrunk with the "stretch by" option in mkvmerge? Is there any program out there that can read the "stretch by" and audio delay attributes within an mkv container header?
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  2. Thanks but unfortunately I can't use xvid4psp on my computer, it requires netframework 3.0 and I can't install that on my computer (long story). The poster in that topic said ffrebuilder solved his problem and xvid4psp seems to just be a GUI for ffrebuilder and other tools but I haven't been able to find a standalone version of ffrebuilder.
    Also, does anyone know why the mkv extraction tools would extract a different number of video frames than media info reports the initial video has? I think my problem isn't about stretched audio, but somehow a badly extracted video stream.
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  3. copy and paste the text information from mediainfo back here (view=>text)
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  4. Sure thing, this is the original MKV with 132090 frames: (oops, I just realized I made a mistake of 1000 frames in my initial post but the discrepancy is still 19 frames, 132090 VS 132109)

    General #0
    Count : 178
    Count of stream of t : 1
    Kind of stream : General
    StreamKindID : 0
    Count of video strea : 1
    Count of audio strea : 1
    Count of text stream : 4
    Count of chapter str : 1
    Codecs Video : MPEG-4 AVC
    Video_Language_List : English
    Audio codecs : AC3
    Audio_Language_List : Japanese
    Text codecs : VobSub / VobSub / VobSub / VobSub
    Text_Language_List : English / French / Spanish / Portuguese
    Chapters_Language_Li : English
    Complete name : G:\Tokyo Godfathers.mkv
    Folder name : G:
    File name : Tokyo Godfathers
    File extension : mkv
    Format : Mk
    Format : Mk
    Codec : Mk
    Codec : Mk
    File size : 1005221751
    File size : 959 MiB
    File size : 959 MiB
    File size : 959 MiB
    File size : 959 MiB
    File size : 958.7 MiB
    PlayTime : 5509262.000
    PlayTime : 1h 31mn
    PlayTime : 1h 31mn 49s 262ms
    PlayTime : 1h 31mn
    PlayTime : 01:31:49.262
    Bit rate : 1459682
    Bit rate : 1460 Kbps
    Encoded date : UTC 2008-11-22 03:26:17
    Writing application : mkvmerge v2.4.0 ('Fumbling Towards Ecstasy') built on Oct 11 2008 20:22:12
    Writing library : libebml v0.7.8 + libmatroska v0.8.1
    Cover : Yes

    Video #0
    Count : 77
    Count of stream of t : 1
    Kind of stream : Video
    StreamKindID : 0
    ID : 1
    UniqueID : 1
    Codec : V_MPEG4/ISO/AVC
    Codec : MPEG-4 AVC
    Codec/Info : MPEG4 ISO advanced profile
    Codec/Url : http://ffdshow.sourceforge.net/tikiwiki/tiki-index.php?page=Getting+ffdshow
    PlayTime : 5503750
    PlayTime : 1h 31mn
    PlayTime : 1h 31mn 43s 750ms
    PlayTime : 1h 31mn
    PlayTime : 01:31:43.750
    Width : 688
    Width : 688 pixels
    Height : 384
    Height : 384 pixels
    Pixel Aspect Ratio : 1.000
    Display Aspect ratio : 1.792
    Display Aspect ratio : 16/9
    Frame rate : 23.976
    Frame rate : 23.976 fps
    FrameCount : 132090
    Language : en
    Language : English

    Audio #0
    Count : 62
    Count of stream of t : 1
    Kind of stream : Audio
    StreamKindID : 0
    ID : 2
    UniqueID : 2
    Codec : A_AC3
    Codec : AC3
    Codec/Info : Dolby AC3
    Channel(s) : 6
    Channel(s) : 6 channels
    Sampling rate : 48000
    Sampling rate : 48 KHz
    SamplingCount : 264444576
    Language : ja
    Language : Japanese

    Text #0
    Count : 53
    Count of stream of t : 4
    Kind of stream : Text
    StreamKindID : 0
    ID : 3
    UniqueID : 3673329857
    Codec : S_VOBSUB
    Codec : VobSub
    Codec/Info : The same subtitle format used on DVDs
    Language : en
    Language : English

    Text #1
    Count : 53
    Count of stream of t : 4
    Kind of stream : Text
    StreamKindID : 1
    ID : 4
    UniqueID : 400480429
    Codec : S_VOBSUB
    Codec : VobSub
    Codec/Info : The same subtitle format used on DVDs
    Language : fr
    Language : French

    Text #2
    Count : 53
    Count of stream of t : 4
    Kind of stream : Text
    StreamKindID : 2
    ID : 5
    UniqueID : 2152038064
    Codec : S_VOBSUB
    Codec : VobSub
    Codec/Info : The same subtitle format used on DVDs
    Language : es
    Language : Spanish

    Text #3
    Count : 53
    Count of stream of t : 4
    Kind of stream : Text
    StreamKindID : 3
    ID : 6
    UniqueID : 1174871521
    Codec : S_VOBSUB
    Codec : VobSub
    Codec/Info : The same subtitle format used on DVDs
    Language : pt
    Language : Portuguese

    Chapters #0
    Count : 46
    Count of stream of t : 1
    Kind of stream : Chapters
    StreamKindID : 0
    Language : en
    Language : English
    1 : 00:00:00.000 Start
    2 : 00:08:36.140 Guardians for a Night
    3 : 00:12:04.974 Gin's Past
    4 : 00:14:10.766 Second Thoughts
    5 : 00:16:46.688 The Key
    6 : 00:17:30.507 Something Smelss
    7 : 00:20:50.958 The Cemetery
    8 : 00:23:09.554 Blocking a Public Thoroughfare
    9 : 00:25:33.039 His Daughter's Wedding
    10 : 00:26:47.222 "Her Name's Sachiko."
    11 : 00:27:46.539 Kidnapped
    12 : 00:29:49.496 "We're Not Action-Movie Heroes."
    13 : 00:33:32.760 Last Request
    14 : 00:35:30.002 The Nursing Station
    15 : 00:36:26.809 New Year's Cleanup
    16 : 00:37:58.059 Miyuki's Past
    17 : 00:40:54.827 Lost Children Found
    18 : 00:45:31.078 Hana's Past
    19 : 00:52:02.502 The Neighbors Remember
    20 : 00:54:52.914 A Child Never Forgets Its Parents
    21 : 01:00:33.246 Gin's Daughter
    22 : 01:05:38.142 The Weeping Red Devil
    23 : 01:08:02.703 Sachiko
    24 : 01:10:41.320 Sachiko's Husband
    25 : 01:16:08.080 In Pursuit of Stolen Goods
    26 : 01:22:03.702 "I Want to be Reborn."
    27 : 01:24:32.776 Hana Saves the Baby
    28 : 01:25:29.749 The Final Miracle
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  5. And this is a test remux done with mkvtoolnix, a simple extract of the video and audio stream and a remux (ending with 132109 frames):

    General #0
    Count : 178
    Count of stream of t : 1
    Kind of stream : General
    StreamKindID : 0
    Count of video strea : 1
    Count of audio strea : 1
    Count of text stream : 0
    Count of chapter str : 0
    Codecs Video : MPEG-4 AVC
    Audio codecs : AC3
    Complete name : G:\Tokyo Godfathers_remux.mkv
    Folder name : G:
    File name : Tokyo Godfathers_remux
    File extension : mkv
    Format : Mk
    Format : Mk
    Codec : Mk
    Codec : Mk
    File size : 998438388
    File size : 952 MiB
    File size : 952 MiB
    File size : 952 MiB
    File size : 952 MiB
    File size : 952.2 MiB
    PlayTime : 5510088.000
    PlayTime : 1h 31mn
    PlayTime : 1h 31mn 50s 88ms
    PlayTime : 1h 31mn
    PlayTime : 01:31:50.088
    Bit rate : 1449615
    Bit rate : 1450 Kbps
    Encoded date : UTC 2011-05-22 04:13:23
    Writing application : mkvmerge v4.0.0 ('The Stars were mine') built on Jun 6 2010 16:18:42
    Writing library : libebml v1.0.0 + libmatroska v1.0.0

    Video #0
    Count : 77
    Count of stream of t : 1
    Kind of stream : Video
    StreamKindID : 0
    ID : 1
    UniqueID : 2036307623
    Codec : V_MPEG4/ISO/AVC
    Codec : MPEG-4 AVC
    Codec/Info : MPEG4 ISO advanced profile
    Codec/Url : http://ffdshow.sourceforge.net/tikiwiki/tiki-index.php?page=Getting+ffdshow
    PlayTime : 5504541
    PlayTime : 1h 31mn
    PlayTime : 1h 31mn 44s 541ms
    PlayTime : 1h 31mn
    PlayTime : 01:31:44.541
    Width : 688
    Width : 688 pixels
    Height : 384
    Height : 384 pixels
    Pixel Aspect Ratio : 1.000
    Display Aspect ratio : 1.792
    Display Aspect ratio : 16/9
    Frame rate : 23.976
    Frame rate : 23.976 fps
    FrameCount : 132109

    Audio #0
    Count : 62
    Count of stream of t : 1
    Kind of stream : Audio
    StreamKindID : 0
    ID : 2
    UniqueID : 1673317288
    Codec : A_AC3
    Codec : AC3
    Codec/Info : Dolby AC3
    Channel(s) : 6
    Channel(s) : 6 channels
    Sampling rate : 48000
    Sampling rate : 48 KHz
    SamplingCount : 264484224
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  6. so mkvextract and then mkvmerge back into mkv will show the framecount difference ?

    some encoding options (open gop) are not compatible with current mp4 container specs , but that doesn't explain the frame count discrepancy; it just can cause sync and seek issues. The metadata is missing as well (I'm assuming x264 was used to encode the mkv ?)

    try muxing with ffmpeg without mkvextract

    ffmpeg -i input.mkv -vcodec copy -acodec copy output.mp4


    The other possibility is VFR . You would have to mux in timecodes to the mp4 container, but that doesn't explain framecount difference either
    Last edited by poisondeathray; 24th May 2011 at 13:23.
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  7. Hmm... Here's the command line I used:

    "C:\Documents and Settings\xxx...\FFmpeg\FFmpeg-git-N-30172-g3c20c0e\ffmpeg.exe" -i "G:\Tokyo Godfathers.mkv" -vcodec copy -acodec copy "G:\output.mp4"

    The resulting mp4 took like half a second to "mux" and ended up being 16KB and of course non usable. What's wrong?
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  8. what does the log say ?
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  9. I've never used ffmpeg before and I can't find the log
    I'm suspecting I'm doing something wrong with ffmpeg because I tried on another mkv file I had and a straight mkv to mkv copy done on ffmpeg didn't work either...
    I've cut down the original mkv to a 20MB piece with only the audio and video (no demuxing, a straight edit cut from mkvtoolnix while only retaining the video and audio streams). Media info shows it as having 3043 frames, but again once extracted it shows 3050 frames. The piece is only 20MB, if anyone would like to download it and tell me what they think of that problem, I'd really appreciate it.

    Here's a link:
    http://www.megaupload.com/?d=9YHARLSI
    Alternate link in case:
    http://www.mediafire.com/?2xdp6p2w462hyyt
    Last edited by PlanetIndigo; 24th May 2011 at 14:53. Reason: Alternate Link
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  10. I've tried to use a GUI for ffmpeg (FFE) to try and get a log, but it doesn't allow me to change the extension from mkv to mp4 if I select "copy" for both audio and video streams. Can you only change containers using ffmpeg if you reencode 1 or more streams?
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  11. "The file you are trying to access is temporarily unavailable. Please try again later."

    you can upload it directly to this site if <30MB , or another host e.g. mediafire.com, sendspace.com

    ffmpeg can copy streams, you don't need to encode
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  12. Yeah, for some reason the first link seems to be acting up, it worked at first, then didn't work and now it works again. I uploaded it to mediafire as a backup option.
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  13. eac3to is reporting errors and overlaps in the video stream.

    That's probably why everything thinks there are 3051 frames

    why do you want to re-wrap into mp4 ?

    is it just this file that is the problem ?
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  14. I wanted to remux it into mp4 for my PS3. I've had a couple issues with audio sync in mkv --> mp4 in the past, but I'm not sure if those were caused by a discrepancy in the video frame # as this is the first time I've actually taken notice of this.
    Out of curiosity, are you using a GUI for eac3to? If so, which one would you recommend?
    Also, did you try ffmpeg on that video and did it produce an mp4 with 3050 video frames as well?
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  15. I used command line for eac3to and ffmpeg

    all attempts to demux or re-wrap with multiple programs resulted in 3051, not 3050

    raw elementary stream parsers indicate 3051 frames

    I think the fps is a bit off in that file (it's not perfect 24000/1001) , and the timecodes suggest this as well . But even muxing with timecodes or modified timecodes result in different figures

    Either it's damaged, or the person who made it didn't do a good job . I would leave it as is; I don't see a way around it
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  16. I'm not very familiar with how to read timecodes, for future reference, what made you say in those timecodes that the fps shouldn't be 23.976?
    Also, assuming that the file isn't damaged, how would someone would go at encoding a video file that shows X number of frames once in a container then a different x+y number once the video stream was demuxed? Is it what the "stretch by" field do for a video stream in mkvmerge? (I take it it doesn't modify the fps since it's an entirely different option so it would duplicate or remove some frames maybe?)

    PS: I was saying 3050 frames because when I was extracting the streams from the sample I posted then remuxing them into a a new mkv, media info was reporting the new mkv as having 3050 frames. Now that I paid attention to the number reported in TS muxer when it demuxes the initial track it shows it extracted 3051 frames like you said. The oddities continue...
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  17. Well mediainfo isn't necessarily correct. I wouldn't go by that. It just reads header information and can be wrong.

    A stream parser will examine every frame, and is more accurate




    I'm saying if done properly, it should be 24000/1001 , not 23.976 which is an approximation

    but this video is reported by directshow (in avisynth) to be 1000000/417083 , which is close . This reports 3044 through directshow

    other programs report 3051 frames and fps to be 24101/1001 or fps 24.0799

    Both are probably wrong from the original source that this was encoded from. You can bet money that the original source was 24000/1001




    If you look at the timecodes when demuxed with mkvextract, or use ffms2 in avisynth to print the timecodes you will see irregularities, like repeats

    eac3to also reports errors




    the stretch field won't do anything , because that's a linear stretch, so you make one part in sync, but other parts out of sync.

    You can try those odd values for the fps field, they might work
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  18. Well, I have given up on that video. After tinkering with it and skewing the audio then adjusting the fps slightly up (23.978), I had the beginning and the end synced but the middle was off, so it's definitely not a straight stretch...
    Despite not being successful with fixing this vid, I want to thank you a lot poisondeathray for all your help, much appreciated!
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