I'm desperately trying to sync the audio of this video file...
... with this video file:Code:Format : AVI Format/Info : Audio Video Interleave File size : 451 MiB Duration : 53 min 52 s Overall bit rate : 1 170 kb/s Writing application : Lavf57.25.100 Video ID : 0 Format : MPEG-4 Visual Format profile : Advanced Simple@L5 Format settings : BVOP2 Format settings, BVOP : 2 Format settings, QPel : No Format settings, GMC : No warppoints Format settings, Matrix : Default (H.263) Muxing mode : Packed bitstream Codec ID : XVID Codec ID/Hint : XviD Duration : 53 min 52 s Bit rate : 1 029 kb/s Width : 720 pixels Height : 404 pixels Display aspect ratio : 16:9 Frame rate : 23.976 (24000/1001) FPS Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Scan type : Progressive Compression mode : Lossy Bits/(Pixel*Frame) : 0.148 Stream size : 397 MiB (88%) Writing library : XviD 64 Audio ID : 1 Format : MPEG Audio Format version : Version 1 Format profile : Layer 3 Codec ID : 55 Codec ID/Hint : MP3 Duration : 53 min 52 s Bit rate mode : Constant Bit rate : 128 kb/s Channel(s) : 2 channels Sampling rate : 48.0 kHz Compression mode : Lossy Stream size : 49.3 MiB (11%) Alignment : Aligned on interleaves Interleave, duration : 24 ms (0.58 video frame) Interleave, preload duration : 24 ms
... and I can't seem to figure out what's wrong, despite a lot of attempts.Code:General Format : Matroska Format version : Version 4 / Version 2 File size : 765 MiB Duration : 55 min 10 s Overall bit rate : 1 939 kb/s Encoded date : UTC 2018-09-09 12:19:09 Writing application : mkvmerge v26.0.0 ('In The Game') 64-bit Writing library : libebml v1.3.6 + libmatroska v1.4.9 Video ID : 1 Format : HEVC Format/Info : High Efficiency Video Coding Format profile : Main@L4@Main Codec ID : V_MPEGH/ISO/HEVC Duration : 55 min 10 s Bit rate : 1 740 kb/s Width : 1 920 pixels Height : 1 080 pixels Display aspect ratio : 16:9 Frame rate mode : Constant Frame rate : 23.976 (24000/1001) FPS Color space : YUV Chroma subsampling : 4:2:0 Bit depth : 8 bits Bits/(Pixel*Frame) : 0.035 Stream size : 687 MiB (90%) Default : Yes Forced : No Audio ID : 2 Format : AAC Format/Info : Advanced Audio Codec Format profile : HE-AAC / LC Format settings : Explicit Codec ID : A_AAC-2 Duration : 55 min 9 s Bit rate : 197 kb/s Channel(s) : 6 channels Channel positions : Front: L C R, Side: L R, LFE Sampling rate : 48.0 kHz / 24.0 kHz Frame rate : 23.438 FPS (1024 SPF) Compression mode : Lossy Delay relative to video : 23 ms Stream size : 77.7 MiB (10%) Language : English Default : Yes Forced : No Text ID : 3 Format : UTF-8 Codec ID : S_TEXT/UTF8 Codec ID/Info : UTF-8 Plain Text Duration : 53 min 29 s Bit rate : 92 b/s Count of elements : 1365 Stream size : 36.2 KiB (0%) Language : English Default : Yes Forced : No
- The first audio needs to be slowed down to fit the second video, that's for sure.
- The first video is low-res, and the second one is 1080p.
- So at first I thought it was a mere 25 -> 23.976 fps problem, but it wasn't. The audio shift is much smaller (progressive shift, the max delay is about 6 seconds towards the end for a 55 min video).
- So I also tried 24 -> 23.976, but it wasn't either.
- Some calculations show that the needed duration factor seems to be around 1.002 (the audio should be stretched by that factor), but that factor doesn't match anything that I'm used to. I may be missing something.
I'm not used to reading Mediainfo details, so I don't know what may be wrong nere.
Could you please help ? Many thanks in advance !
PS : please don't mind the total duration of each file, as there are different credits. What matters is that the videos are identical until about 1 min from the end. That's what really matters. That means the audio starts at the same moment (no audio delay at the beginning), and once synced, the audio should remain OK until about 1 min from the end, which would be good enough for me.
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Last edited by Jose Hidalgo; 5th Jun 2020 at 13:45.
If it was just a factor of the audio length, the sync should go out further (either ahead or behind) the further into the
video you go. Sometimes there is a join at a specific point in the video which throws it out right there.
You don't really say what results you're getting but if it's in sync for a passage then suddenly goes out, you may need to divide
it there and work on the pieces separately - then join them together when their done
An alternative is to post the whole of the video and the new audio let somebody else take a look
Thanks for your reply. I really think that it IS just a factor of the audio length, but I'd like to understand what's going on.
I could post the whole audio 1 + video 2 (it's about 800 MB to I could easily give a download link), but would that be allowed?
It's a TV show episode from 1 or 2 years ago. Audio 1 is a french track, and video 2 is a 1080p english version. I'd like to add the french track to the video 2 for personal purposes.
Last edited by Jose Hidalgo; 5th Jun 2020 at 14:26.
Sure, I understand. Well, let's not risk it then.
My GF has the media, but I guess it doesn't count since we live miles apart.
Anyway, thanks for trying to help.
PS : it's not even the show I'm interested in (I've already seen it in english). It's more about the technical mystery of being unable to sync the audio. I don't know where that unusual factor comes from, and the two Mediainfo don't tell me much.
Last edited by Jose Hidalgo; 5th Jun 2020 at 14:51.
Both movies are 23.976 fps, so there is no need to slowing or speeding up anything, but the first has a duration of 53 min 52 s and the second of 55 min 9 s.
So the first audio is to short for the second video.
You can search the correct audio delay with VLC player
Last edited by ProWo; 5th Jun 2020 at 14:57.
ProWo, like I said in my first post, "please don't mind the total duration of each file, as there are different credits".
Anyway, I finally found the problem. One of the videos had a 6-second additional title about 3 min into the video.
Nevermind. You got it already.