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

[Stefano Sabatini]

On date Saturday 2010-12-04 16:17:27 +0100, Stefano Sabatini encoded:
> 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

> From 3c9f6d109bd45ef20f90061b5314d8e02822c741 Mon Sep 17 00:00:00 2001
> From: Stefano Sabatini <stefano.sabatini-lala at poste.it>
> Date: Sat, 6 Nov 2010 03:04:43 +0100
> Subject: [PATCH] Add section describing the filtergraph.
> 
> ---
>  doc/filters.texi |   92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 92 insertions(+), 0 deletions(-)

I'll apply in few days, then feel free to fix it in SVN (especially if
you're a native English speaker and the docs look weird to you).
-- 
FFmpeg = Funny Fierce Moronic Purposeless Egregious Gem