progressive audio sync issues with multiple-chapter MKV H.264 output

ianbtv

New member
Hi all -

I am a new user of VRD products ... just bought TVSuite 5

My primary need is for an editor of TiVo H.264 files. I use kmttg to download from my TiVo Roamio. I'm not doing any conversion - am outputting into MKV H.264

My first edit worked well, except that during playback (with VLC), at each cut point (and new chapter creation) there is a progressive audio sync issue - after 5 chapters it looks to be around 100ms.

If it were constant, I would be able to accommodate for it with playback hardware settings, but a progressive issue is not workable.

I can provide a Dropbox link if anyone wants to see this effect.

Has this been discussed in the past, or do any seasoned users have ideas?

Thank you in advance -

ianbtv
 

jmc

Active member
"Tools">Adjust Audio"

If progressive you may have to split the video into small enough segments and adjust each one.
Then join them back together.

EDIT...
Or adjust a segment and save it to the "Joiner".
Then "Create Video" after all segments are adjusted and in the "Joiner".
 
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Danr

Administrator
Staff member
First off, try Version 6 it's just been released. You can download it from our website. Then if you still have sync issues send us the videoredo log file to support AT videoredo.com. You can access our log files from the help menu.
 

ianbtv

New member
First off, try Version 6 it's just been released. You can download it from our website. Then if you still have sync issues send us the videoredo log file to support AT videoredo.com. You can access our log files from the help menu.
Hi DanR -

I redid the editing using v6. Instead of a progressive audio sync issue, now there is a constant but significant audio sync issue of all material after the first scene. I have played-back with VLC and WMP, plus my Samsung TV's native player, and see this with all of them. Curiously, if I playback the edited video in TVS v6 itself, there is no sync issue.

I'm uploading the log file here and also sending it to support. Also, here is a Dropbox link to a folder containing the test material for anyone to peruse - it contains the original .ts file, the edited .mkv file I created from it, vprj file and aforementioned log file:


Thanks to all for your advice and help -

ianbtv
 

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tobyW

Member
Curiously, if I playback the edited video in TVS v6 itself, there is no sync issue.
Hi ianbtv, I'm another user. If I recreate and playback your "edited video in TVS", my eagle eye can detect sync issues near the end.
The clue to the cause is in the message that pops up when you create the edited file, telling you it has removed 58 video frames (to correct for transmission errors).

You might like to try the following experiment, on the "Apollos Moon Shot - Rocket Fever (07_07_2019) .ts" file in your dropBox:-
- Load your source .ts file, and run VRD's QuickStreamFix (under the Tools menu). Apply your edits to the resulting qsf'd .ts file, and save it as a .ts file.
- Load this new edited file into an instance of VRD, and go to time code 00:30:23:55 (a scene change, easy to find).
- Load your old edited file into another instance of VRD, and go to time code 00:30:24.25 (the same scene change).
- Inspect them side by side, play them around that point, and see how the QSF'd file plays correctly!

Therefore, to overcome transmission timing problems, it's best to ALWAYS run QuickStreamFix on your source file BEFORE editing the file.

You might discover that transmission errors are not the only source of problems. For example, if I push my video compression settings too far my Samsung TV will lean over. In the end, the trick is to make the lipsync error unnoticeable, by making sure the audio is always later than the video, never earlier. You can delay the audio in VRD, either in an output profile, or in the editor's "Adjust Audio" under the Tools menu as jmc mentioned earlier.

Welcome to the VRD user community, and I hope this helps,
tobyW
 

ianbtv

New member
... The clue to the cause is in the message that pops up when you create the edited file, telling you it has removed 58 video frames (to correct for transmission errors).
...
Therefore, to overcome transmission timing problems, it's best to ALWAYS run QuickStreamFix on your source file BEFORE editing the file. ...
Thank you, tobyW - that did the trick! Using QSF on the TS file before editing eliminated dropped frames in the final product (and thus the equivalent time of audio delay).

Much appreciated!

ianbtv
 
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