The VideoLAN Forums

Hi, here is a possible workflow that would greatly simplify the way to sync subtitles (I know about the existing solutions, but they are difficult to use and an improvement would be welcomed).

Sample use case :
Below is a possible use case, when subtitles are late when compared to the audio.

Step 1 : Detect (“hear and see”) that subtitles are out of sync
(No high tech voice recognition needed here, just let the user detect it)


Step 2 : Press “Ctrl H” when you recognize a sentence you hear on the audio


Step 3 : Press “Ctrl J” when you read the same sentence in the subtitle


Step 4 : Press “Ctrl K” to correct the sync



Technical details

Shortcuts
The proposed workflow uses 3 shortcuts (^H, ^J, ^K) that are inspired by the already existing “J” and “H” shortcuts for subtitles synchronization


Subtitles delay
The result delay would applied as when entering the delay into the “Track synchronization” window (except that this way of calculating it requires much less brain cycles)


Note: as of now, if you enter a delay of 30 seconds in that window, you need to actually wait 30 seconds for the sync to be performed! Could that be improved?

What to do when subtitles are in advance when compared to the audio?
The principle would be the same, except that you would use the shortcuts in the following order :

Step 1 : Press “Ctrl J” --> Save subtitle timestamp when you read and memorize a sentence
Step 2 : Press “Ctrl H” --> Save audio timestamp when you hear the same sentence
Step 3 : Press “Ctrl K” --> Apply the delay

What about subtitle speed adjustments?
This process does not give a solution here.
However, by using the described shortcuts periodically (say, every 5 minutes), it might even still be usable.

Images on my first post have been lost. Here is a working doc with the correct images :
https://docs.google.com/document/d/1v58 ... 8n578/edit#

If you did this at two different points in the video you could even scale up or down the speed of the subtitles ... just saying ...

If you can use Subtitler (lite) to play SRT subtitles (the extension works well with fixed subtitle path), then you can test your idea: viewtopic.php?f=29&t=97791&p=373422#p373422
Hotkeys "Ctrl+h" and "Ctrl+j" are already engaged by VLC. I have defined "Shift+h", "Shift+j" and "Shift+k" instead.

This feature could assist timing dialog box, where you could then perform fine adjustment of acquired numerical values.
Then I would define adjustable time corrections like:
time*factor+delay; for example factor=23.976/25.000

Oops, mederi,

I forgot to post an update to my query on the forum.
I have posted a patch to the devel mailing list that adresses my suggestion, and it has been accepted in the main repo : see the patch at
http://mailman.videolan.org/pipermail/v ... 92671.html

Added the following shortcuts (and made them configurable):
- Shift-H: sets a timestamp bookmark on the audio
- Shift-J: sets a timestamp bookmark on the subtitle
- Shift-K: corrects the delay between both bookmarks
- Command-Shift-K: resets the delay

Many thanks for your kind attention anyway, and I will look at your extension,
since I have other ideas concerning subtitles sync that could be easier done with it

At first you request a new feature, then you provide your own patch. You are from a different class Perhaps you could help to fix/implement also other open issues in VLC. VLC really needs skilled C++ volunteer developers.

At first you request a new feature, then you provide your own patch. You are from a different class

Yes, you are. This is really cool

even in the most difficult case (subs progressively coming earlier and earlier than due time), i managed to synchronize subs in 1 minute, with SubtitleEdit (free GNU program ))

A quick 45 seconds video tutorial that explains how to use this feature : https://www.youtube.com/watch?v=27Kiqu3dZDY

Nice.