[Enhancement]: Fix _Slightly_ misplaced chapters via silence detection

[samosbor]

Fix Slightly misplaced chapters via silence detection

I find that often, the chapter matching feature gets very close to the correct timestamps for chapter marks. However, usually there is a slight offset by a few seconds. Sometimes the offset is consistent, sometimes it is not (maybe due to encoding at slightly different speed).

M4B-tool has a feature to adjust chapters via silence detection. With the current chapter fix features getting us most of the way there, I think the silence detection would work very well.

[advplyr]

That silence detection for chapters is a good idea. I can see how to detect the silence using ffmpeg and grab those timestamps, but I think the difficult part here will be the UI/UX.

Do you have a UI in mind for how this would be done?

There are a lot of edge cases I can think of, like you may not find matching chapters from audible but you still want to detect the chapter timestamps using silence. The number of silences might not match up with the chapters from audible.
Like how it was done in m4b-tool, we will probably want to add some way for the user to adjust the length of the silence.

On a similar note, the chapter editor was planned to have the ability to shift all chapter times X seconds. That would be separate from silence detection but seems relevant to mention here.

[SpeakingOfBrad]

I know this is an older request, so I hope it's okay to add my thoughts here.

For the UI aspect I imagine a simple "Adjust via silence detection" button near the top of the chapter edit page that will do its best to adjust the chapter timestamps to the end of the nearest silence of at least 1.5 seconds (or whatever you decide the default should be).
That would probably be enough for most use cases where the chapters are just slightly off.

[ZLoth]

This is one of serveral improvements that need to be made to the Chapter Editor.