[FFmpeg-devel] [PATCH] lavfi: reimplement MPlayer's af_pan filter for libavfilter.

Clément Bœsch ubitux at gmail.com
Thu Nov 17 19:21:36 CET 2011

On Thu, Nov 17, 2011 at 07:04:37PM +0100, Nicolas George wrote:
> Le septidi 27 brumaire, an CCXX, Clément Bœsch a écrit :
> > I think you can just say "ported from MPlayer by Clément, and rewritten
> > from scratch by Nicolas" ;)
> > 
> > You did much more work on this than I do :)
> I am not so sure: I did parsing and numeric manipulations, that is "classic"
> work. You did the integration with lavfi, which involves understanding the
> API.

As you wish :)

> > > +pan=stereo:FL<FL+0.5*FC+0.6*BL+0.6*SL:FR<FR+0.5*FC+0.6*BR+0.6*SR
> > Does the syntax allow some spacing? for instance between the ':'?
> Yes, except possibly before the first one. Do you think it would be better
> to include an example with spacing?

If it actually does support it, I think it would be nice yes. I guess
users will look for something more obvious like:


Even if it's only a space I think it greatly improves readability.

Ideally we would even have:

  pan="stereo : FL  <  FL + 0.5*FC + 0.6*BL + 0.6*SL
              : FR  <  FR + 0.5*FC + 0.6*BR + 0.6*SR"

> > Any reason to go up to 63 ATM?
> Do yo see any reason not to? SWR_CH_MAX=16 was too low anyway, as we have
> named channels up to id #30.

No no, I was just curious why we should have various max channels mismatch
we have all over the code, but I have my answer for this one now :)

Clément B.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 490 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20111117/336f5b0e/attachment.asc>

More information about the ffmpeg-devel mailing list