[FFmpeg-devel] [PATCH v3 00/18] Subtitle Filtering

[Hendrik Leppkes]

On Sat, Sep 11, 2021 at 8:02 AM Soft Works <softworkz at hotmail.com> wrote:
>
> At a future point in time, it might make sense merge AVSubtitle into
> AVFrame. I haven't done that yet to avoid cluttering the patchset with
> too much distraction and keep focus on the relevant changes.
>

Actually I would want to see subtitles to fully move into AVFrames
before any filtering, if at all, and not half-assed. That means fully
convert avcodec, deprecate AVSubtitle entirely (and not just shove it
into AVFrame->data), and make them a first-class citizen inside
AVFrame.
Doing it half-assed just for filtering now binds us into that chosen
API for years, and thats something we should try to avoid when we can
do it properly right from the start.

This can (and should) be done independent of filtering (in other
words, avfilter doesn't necessarily need to accept subtitle frames
yet), but it needs to be done *before* filtering, because you would be
fundamentally re-defining the subtitle storage for years to come.
Some developers have started work on this before, but due to time
constraints it mostly got stuck in WIP phases.

- Hendrik