[FFmpeg-devel] [PATCH] lavfi: add aconcat variant for the concat filter

Nicolas George nicolas.george at normalesup.org
Fri Sep 7 11:52:19 CEST 2012

Le primidi 21 fructidor, an CCXX, Stefano Sabatini a écrit :
> This usually takes around ~40/50 lines of dummy code.

Precisely: ~40/50 lines of code for a dubious benefit.

> The ideal solution would be to make the filter autodetect the
> input/output types and reconfigure itself accordingly.
> For example:
> unsharp,showinfo
> will make showinfo work like a video filter:
> atempo,showinfo
> will make it work like an audio filter.

Of course. Note that this is not so easy, because several undetermined
filters may be connected together. But there is nothing impossible here. It
just requires someone with the time and motivation to make the change.

> Right now the filter type is checked when building the graph, we could
> leave the type unset (or specify a set of recognized types,
> e.g. audio+video), and setup the filter link during the configuration
> stage.
> So yes in the long run this would be the better approach.
> In the short term it is still useful to specify:
> aconcat
> rather than:
> concat=v=0:a=1
> but I won't insist on this if you disagree.

Useful, maybe (actually I am not really convinced), but at the cost of 40+
lines of code, I really do not think so.


  Nicolas George

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