Sometimes, when you download a subtitle and try use it while watching a video, you will realize that the subtitle is not synchronized with the video - the text either starts after or before the characters start speaking, or even starts ok but then after a few minutes it starts 'drifting' out of sync with the spoken part. 

There are many reasons why a subtitle may seem out of sync with your video, even though the file itself might be perfectly fine.

 

Here are some of the reasons:

  • Different sources
  • Advertising or commercial cuts
  • Different versions of the video
    • Extra scenes, cut scenes
    • Another intro
  • Badly converted subtitle

Different Sources

A video might come from different places. It can be ripped from a DVD, from a VHS, digitally recorded from a TV and maybe even recorded in a cinema. Sometimes, due to early recording or a missing part of the intro, the subtitle might turn up constantly delayed or advanced.
The origin of the video is one of the most common reasons for what we call "constant displacement", where every line is evenly delayed or advanced. It can be easily corrected with the Basic Synchronizer.

Advertising and commercial ads

Tv recorded videos often include advertising in the middle.
Therefore, any subtitle created for an ad-free version of the video will become desynchronized when the first advert starts.

There are 2 ways of solving this problem. You can either edit the video file and remove the adverts with video editing software, or you can correct the subtitles to accomodate the advertising in the middle. This scenario is rare although it might happen.

To make this kind of correction you need an advanced subtitle editing program, such as Subtitle Workshop.

Different versions of the video (extra scenes, cut scenes, another presentation)

Releases such as extended versions or Director's Cuts of films will often result in unsynchronized subtitles, as the subtitle file may have been made for the standard length version of the film. The same issue occurs in films where some scenes are cut to make the film more available to a wider audience.

Also when some TV series are released in DVD format their length may change, usually due to a change in the length of the introduction to the show. An example is the series 'The Simpsons'. In the original, long intro, Bart travels through Springfield on his skateboard – in the short intro this is cut and he simply arrives immediately home after leaving school.

In this case the solution is much like that for adverts – you need to edit the contents of the subtitle file, usually with a program like Subtitle Workshop.

A badly converted subtitle

The last reason why a good subtitle might not work as expected is a bad format conversion.
All subtitle formats use one of 2 ways to track the passing of time: the number of frames in the video, or the elapsed time.
To convert a frame-based format (example: MicroDVD) into a elapsed time format (example: SubRip), you need the exact frames-per-second rate. Even the slightest error could cause the subtitle to become desynchronised. This type of de-synchronisation is called 'variable displacement' and can be fixed using the Advanced Synchronizer.

A piece of advice: is far easier to use the Search Function to find the correct version of a subtitle for a specific video rather than adjusting the subtitle, even if you have the suitable tools. The worldwide community of subbers is doing a great job, providing excellent quality subtitles. It's very likely that the subtitle you are looking for has already been submitted by someone else.