[MPlayer-DOCS] Draft for -af ladspa manual page entry

[Diego Biurrun]

Ivo writes:
> On Monday 20 December 2004 06:09, Ivo wrote:
> >
> > This is a draft for the manual page entry describing the pending LADSPA
> > plugin audio filter. Like Diego put it on IRC, a rough draft that you
> > guys can work from :-) Seriously, I did my best to describe it, but from
> > previous experience, I know a lot can probably be improved!
> 
> I updated the patch. It now uses the new Audio Filters section Diego created 
> today.

:)

> --- DOCS/man/en/mplayer.1	20 Dec 2004 22:34:47 -0000	1.827
> +++ DOCS/man/en/mplayer.1	21 Dec 2004 00:12:34 -0000
> @@ -3631,6 +3631,39 @@
>  Maximizes the volume without distorting the sound.
>  .RE
>  .
> +.TP
> +.B ladspa=file:label[:controls...]
> +Load a LADSPA (Linux Audio Developer's Simple Plugin API) plugin.
> +This filter is re-entrant, so multiple LADSPA plugins can be used at once.

reentrant

> +.PD 0
> +.RSs
> +.IPs file\ 
> +Specifies the LADSPA plugin library file.
> +If LADSPA_PATH is set, it searches for the specified file.
> +If it is not set, you should supply a fully specified pathname.
> +For example, for the Computer Music Toolkit you can specify 'cmt' if
> +LADSPA_PATH is set correctly; if it's not set, you must

it is

> +specify '/usr/lib/ladspa/cmt.so' (or wherever cmt.so is located on your
> +system).

IMO this example is a bit redundant as I find it quite obvious.  Keep
it if you wish, though.

> +.IPs label
> +Specifies the filter within the library.
> +Some libraries contain only one filter, but others contain many of them.
> +Entering 'help' here, will list all available filters within the specified
> +library.
> +This eliminates the use of LADSPA SDK's listplugins.

use of 'listplugins' from the LADSPA SDK

> +.IPs controls
> +Most plugins have controls.
> +Zero or more floating point values control the behaviour of the loaded plugin.
> +Controls might correspond to gain, threshold, delay, et cetera.

I'd suggest:

Most plugins have controls for things like gain, threshold, delay,
etc.
These controls are set through floating point parameters.

> +You can use LADSPA SDK's analyseplugin to determine how many controls there

.. use the analyse plugin from the LADSPA SDK to determine ..

> +are and what values are valid.
> +You can also add -v to MPlayer's command line.

to the MPlayer command line

> +This will make the ladspa filter more verbose.

Also sounds redundant to me.

> +It will print all available controls to standard output, including the valid
> +ranges for each control.

Hmm, no, not redundant, just maybe shorten it a bit.  "In verbose mode
.. are printed."

Diego