[FFmpeg-devel] lavfi: expected behavior for multiple filter?definitions
Mina Nagy Zaki
mnzaki at gmail.com
Fri Apr 1 20:39:56 CEST 2011
On Thursday 31 March 2011 17:04:05 Stefano Sabatini wrote:
> On date Thursday 2011-03-31 15:21:19 +0200, Mina Nagy Zaki encoded:
> > On Wednesday 30 March 2011 13:09:24 Michael Niedermayer wrote:
> > > On Wed, Mar 30, 2011 at 07:30:32AM +0200, Mina Nagy Zaki wrote:
> > > > What is the expected behavior of:
> > > > ffmpeg -i in.mp3 -af aresample=8000 out1.mp3 -af earwax out2.mp3
> > >
> > > it should behave the same as with video filters.
> > >
> > > [...]
> > They are both equally broken (IMHO) in that only the last -vf/-af is ever
> > evaluated and the rest are discarded.
> Can you verify with the latest git (and corresponding audio branch),
> this should be already fixed.
> For example this works here:
> ffmpeg -i slow.flv -vf scale=200:-1 slow1.mov -vf scale=300:-1 slow2.mov
My bad, it's only audio filters that's broken. -af param is not stored for each
output stream, unlike -vf.
> > Actually each -af could simply add on to
> > the filter graph definition, inserting new links/filters, and then when
> > an output file is specified a new aout/vout is created and linked to the
> > last available open output. This way multiple output files can be
> > inserted easily at different parts of the graph, or even multiple
> > independent chains (and hence independent outputs) can all be connected
> > to a single src.
> This is actually the last design we'll implement, but one step at a
> time, since this will possibly require a major revamp of the ffmpeg.c
Well, I suppose yes. I guess then leave this bug if it's all going to be
redone later anyway.
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