[vlc-devel] [RFC]: Reworking the metadata listener API => writting a proper filter API

Thomas Guillem thomas at gllm.fr
Mon Mar 8 13:14:17 UTC 2021

On Fri, Mar 5, 2021, at 17:25, Rémi Denis-Courmont wrote:
> Le perjantaina 5. maaliskuuta 2021, 17.48.24 EET Thomas Guillem a écrit :
> > Comments are more than welcome!
> There are two major issues here.
> 1) Changing settings in one (or several) filters, as opposed, or in addition 
> to, adding and removing filters to the list, seems to be missing.

Indeed, I was focused on the audio meter usecase, forgetting dynamic filters.

The vlc_filter_entry API could propose a way to change some key/value and forwarding to the correct actual filter on the correct output. What do you think ?

> 2) Changing the filter chain aehad of time while there is zero outputs is 
> impossible. Changing the filter chain while there are more than one outputs 
> will in practice not work either.
> I think both of those are pretty much mandatory to support at least at the 
> LibVLC level.

It will work for VLC Core since all output are exposed, and you able to configure the aout and the vout before the first run.

What do we do for LibVLC, that is an excellent question:
 - Don't expose aout/vouts, only allow the modification of the primary aout/vout (in use) via the libvlc_media_player API.
Advantage: easy to do, cons: we will need to adapt the API again in VLC 5.0 or later when we add multiple output support (I guess it's the plan)
 - Expose the main aout, and all vouts via the libVLC API: adapt the Core API to LibVLC. It was not really in the 4.0 milestone (what about the filter API rework ?). Maybe we should do it now in order to don't change the API again in 5.0.

> -- 
> 雷米‧德尼-库尔蒙
> http://www.remlab.net/
> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel

More information about the vlc-devel mailing list