feature request: enhance disposition management (add options to remove specific disposition & set multiple dispositions)

[droid-xx]

Right now, unless I'm mistaken, we can only 1) set/alter a single disposition per stream, and 2) remove all dispositions from a stream.

It would be nice if we could set multiple dispositions for a stream, for example like this:

ffmpeg -i input.mkv -map 0 -c copy -disposition:s:0 forced,hearing_impaired output.mkv

And also to be able to remove a single or multiple (but not all) dispositions, for example like below:

ffmpeg -i input.mkv -map 0 -c copy -disposition:s:0 forced=0,hearing_impaired=0 output.mkv

[mkver]

You can already do this: Remove forced and hearing impaired: -disposition:s:0 -forced-hearing_impaired. Set multiple dispositions (without unsetting what was set before (i.e. logical OR)): +forced+hearing_impaired

[droid-xx]

Good to know, thanks