[FFmpeg-devel] [PATCH 2/3] Add section describing the filtergraph.

[Stefano Sabatini]

On date Friday 2010-12-03 00:35:46 +0100, Michael Niedermayer encoded:
> On Thu, Dec 02, 2010 at 11:43:28PM +0100, Stefano Sabatini wrote:
> > On date Thursday 2010-12-02 23:07:37 +0100, Michael Niedermayer encoded:
[...]
> > > > + at section Filtergraph syntax
> > > > +
> > > > +A filtergraph can be represented using a textual representation, which
> > > > +is recognized by the @code{-vf} and @code{-af} options of the ff*
> > > > +tools, and by the @code{av_parse_graph()} function defined in
> > > > + at file{libavfilter/avfiltergraph}.
> > > > +
> > > 
> > > > +A filter in the graph is called filternode.
> > > 
> > > why?
> > 
> > That was to keep a consistent terminology:
> > filternode
> > filterchain
> > filtergraph
> 
> not consistent at all.
> consistent is either
> filter, filterchain, filtergraph
> or
> filternode, filternodechain, filternodegraph
> but later is just a hard to read mess
> 
> 
> > 
> > if you have a better suggestion you're welcome. Basically I'm
> > preferring this term in favor of "filter" (which is more related to
> > the "class" concept of filter) and "filter instance" (which would be
> > too long and not consistent with the other terms and less expressive).
> >  
> > > > +
> > > > +A sequence of connected filternodes, each one connected to the
> > > > +previous one in the sequence, is called a filterchain. A filterchain
> > > > +is represented by a list of ","-separated filternode descriptions.
> > > > +
> > > 
> > > > +A sequence of filterchains completely describe a filtergraph. A
> > > > +filtergraph is represented by a list of ";"-separated filterchain
> > > > +descriptions.
> > > 
> > > What is a sequence of filterchains
> > 
> > What is a sequence of pigs?
> 
> a ordered n-tuple of pig elements
> but applied to a filterchain this says nothing its just a space filler
> sequence is too generic without further explanation
> 
> 
> > 
> > Rephrased:
> > 
> > |A filternode is a filter instance which is a node of a filter graph.
> 
> uhm, we are back to square one.
> we do not have 3 different kinds of filters in this text so the use of
> 3 different terms to refer to a filter instance is just confusing

New attempt:
* removed the confusing term "filternode", replaced by "filter"
* added explanation of the relationshop between a filter and its
  filter class
* removed the graph2dot mention (incoming patch for that)
* misc minor changes

And since this is sucking from me a lot of time and effort, I'm
tempted to just commit it and then let you fix it on SVN.
-- 
FFmpeg = Forgiving Funny Martial Patchable Elitarian God