[FFmpeg-devel] [PATCH 0/5] Properly handle CEA-708 caption data when transcoding

[Devin Heitmueller]

On Wed, Mar 29, 2023 at 8:46 PM Andreas Rheinhardt
<andreas.rheinhardt at outlook.com> wrote:
>
> Devin Heitmueller:
> > This patch series is intended to address long-standing known issues where
> > CEA-708 caption data is either duplicated or corrupted (i.e. 50% of the data
> > is lost).  We employ an intermediate queue, which is available to filters that
> > change the frame rate of the video, which stashes the 608/708 data and
> > reconstructs properly formed 708 tuples on the output side (injecting
> > appropriate padding as needed).
> >
> > The common functions are implemented in libavutil, but I am open to
> > suggestions.  While all the users in this patch series are within
> > libavfilter, there are use cases where this functionality would
> > be useful within libavformat (which is why libavutil was chosen).
> >
>
> If it is not used now outside of lavfi, it should be in lavfi to allow
> to change it when it turns out that changes are needed.

So I was thinking along the same lines.  This would allow the API to
mature and change as needed without worrying about ABI breakage, which
would be useful since the API is relatively new and might need
tweaking.

Thanks for the suggestion.  I'll move it into libavfilter in the next
patches I submit (pending any other feedback/comments).

Devin

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Devin Heitmueller, Senior Software Engineer
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