[MPlayer-dev-eng] [PATCH PROPOSAL] -vf option, or soon no more scanf in the vf's

[Alban Bedel]

Hi D Richard Felker III,

on Fri, 14 Mar 2003 12:56:23 -0500 you wrote:

> On Fri, Mar 14, 2003 at 06:01:11PM +0100, Alban Bedel wrote:
> > 
> > Hi,
> > 
> > I wrote the needed stuff to have something better to configure the
> > vf's. That is the vf will be able to just define their options and get
> > a pre-filed struct at open.
> > How it work : The vf_info struct is extended with a new field (it's
> > shit i know but that's really needed) wich (optionaly) contain a
> > pointer to a description of the filter parameters. The config parser
> > use these descriptions to check that all options for each filter are
> > valids. If all options are valids a list of the wanted filters and
> > their options is build. Then when the filter chain in build a config
> > struct is created for each filter and setted like needed. Finnaly the
> > filter get the config struct filled with all users settings at the
> > open call.
> > 
> > Now we have 2 ways to pass the config struct to the vf : either via
> > the arg param of the open call or make the filter describe it's
> > private struct and create it for him. The former seems more logical
> > but it conflict with the current system (ie we can't sanly use the
> > same params with completly differents arguments). Also most of the
> > time the priv struct contain not much more than the users options, so
> > most vf will end up in just copying it in their priv struct. So i
> > choosed to create the priv struct for the vo as it also keep the
> > changes small atm (ie. a vf that have an option description should
> > check to see if the priv field is not NULL).
> 
> I'm not sure yet if this is a good idea. Comments, anyone?
> 
> > The syntax now ;) The list is now in the right order, otherwise it's
> > the same syntax. But you can also put the parameters inside [] or {}
> > and use  the same syntax as the suboptions. ex :
> > -vf scale=[h=500:chr-drop=2],flip
> 
> What are [] or {} needed for? And does the old in-order params syntax
> still work, i.e. scale=640:480 rather than scale=[w=640:h=480]?
The [] or {} are needed to distinct with the old syntax wich work.
> 
> > Also giving help as parameter will display a list of all options.
> 
> This is total nonsense, since you have to run a dummy movie to get
> help. Even more nonsense if it exits mplayer and leaves the terminal
> screwed up like the old -vop pp=help.
No, it's run at the option parsing level, so before getch2. No problems
with that.
> > PS: These 'new' things only work for vf that support it (with this
> > patch only scale). Others can only use the old syntax.
> 
> They also work with -vop detc since it already works that way. :)
I have to take a look this filter.
	Albeu