Automatically change playback speed by subtitles

[ThomasArdal]

Hi. I'm using VLC to play pretty much all my video-files. I usually playback stuff like tv-series at 1.5x or 2.0x speed and I find it to work great. My problem is, that I constantly need to change up and down in speed, to be able to have time to read the subtitles. When a lot of stuff is going on, the optimal speed for me is 1.5, where in the boring scenes, I can watch and understand everything fine on 2.0 speed.

I was thinking if there's an extension for VLC, which analyzes either the video or alternative the subtitles file for the density of speech in the current video. The extension could then turn the speed up and down, depending on how much is going on. If the extension isn't available, how hard is it to develop one?

[Rémi Denis-Courmont]

Quite hard, unless you'd already know the maths behind such a detection.

[ThomasArdal]

Agreed, it would be very hard to analyze the video. But the subtitle files contain start times for all lines. It should be pretty simple to analyze the density of speech by the start times, right?

Example:

00:00:00 "Hello"
00:00:05 "World"

The "Hello" text is visible for five seconds. It takes like 1 second to read it, so the video could be played at double speed until 05 seconds.

[Rémi Denis-Courmont]

Maybe. But that would feel rather awful when constant changes in speed.

And anyway, the only way to determine the answer is to try to implement it.