[Gnash-dev] Another go at configuring the mediahandlers/decoders

[Tomas Groth]

Hi all,

It's once again time to reconsider the way the media handlers are chosen...
At the moment I'm doing some work on the NetStream and Sound classes, and the
soundhandlers, and while I'm at it, why not change the configuring as well?
The goals are:
 * Make it possible to have 2 soundbackends in 1 gnash-setup.
 * Minimize the use of the ffmpeg mp3-decoder, since it is known not to be the
best around, so we want to use madlib whenever possible.

How to do it:
Get rid of the --enable-media=x, and instead use --enable-gst, --enable-ffmpeg
and --enable-mad. To disable a backend just use the corresponding --disable-x.

When gst is enabled, the backend for it will be compiled, and if chosen at
runtime it will be used to decode and play all media.

When ffmpeg is enabled, the backend for it will be compiled, and if chosen at
runtime it will be used to decode and play all media, except if mad is enabled,
in which case mad will do the mp3-decoding.

When mad is enabled, the backend for it will be compiled, and if chosen at
runtime it will be used to decode and play all mp3-audio. If mad is enabled and
ffmpeg is not, only audio will be available when playing video from sites like
youtube.

ffmpeg and mad uses the same SDL backend for audio output, and are therefore
tightly connected. 

At runtime or in .gnashrc a default soundhandler should be selected, perhaps
using "set soundhandler sdl" and "set soundhandler gst" in .gnashrc, and -snd
<sdl|gst> on the commandline.


Feel free to comment, and make suggestions on how this should be done!

cheers,

Tomas