[FFmpeg-devel] [PATCH] Port gradfun to libavfilter (GCI)

[Stefano Sabatini]

On date Wednesday 2010-12-01 17:37:39 +0100, Michael Niedermayer encoded:
> On Wed, Dec 01, 2010 at 12:07:22AM +0100, Stefano Sabatini wrote:
> > On date Monday 2010-11-29 21:48:18 -0500, Nolan L encoded:
> > > On Mon, Nov 29, 2010 at 7:18 AM, Nolan L <nol888 at gmail.com> wrote:
> > > 
> > > > As part of a GCI task, I've ported the gradfun debanding filter from
> > > > mplayer to libavfilter.
> > > >
> > > > The patch includes changes to the build system to account for CPU
> > > > optimizations that weren't present previously.
> > > >
> > > > There is a SSE2 method that remains unported due to lack of SSE2 detection
> > > > in the configure script that I wasn't quite sure how to add.
> > > >
> > > 
> > > Here is the resulting patch from the first round of feedback. Things that
> > > still need to be addressed (mostly with the asm):
> > >     -Factoring the asm; I don't have enough asm experience to do this.
> > >     -alignment issues with the asm code. (hopefully someone more experienced
> > > can take care of this.)
> > >     -gpl vs lgpl
> > 
> >  
> > > I looked at direct rendering, and decided that it would be simpler to keep
> > > it as is. If someone could point out a quick way to implement this without
> > > almost rewriting the filter I'd be happy to oblige.
> > 
> > Direct rendering in this context simply means that the filter doesn't
> > request a new buffer for the picture, but will directly write in the
> > buffer passed by the start_frame function (check the drawbox filter
> > for an example).
> > 
> > Note that this isn't generally possible, in the case you process the
> > neighborhood of each processed pixel like you're doing in this filter
> > (so you need those values not be altered). Point filters (e.g. the eq
> > filter) only process the pixel so they can don't need to write the
> > output in a separate buffer.
> 
> it sounds like you confuse direct with inplace rendering

yes, it was improper terminology but that was what I believed Baptiste
was meaning.
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