Re: [orca-list] [ANNOUNCE] libao (new audio driver for speechd including working pulseaudio support).

I had the chance to test this earlier today. It works very well as far as I can tell.  Great job.

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On Mon, 2009-12-21 at 12:18 -0500, Bill Cox wrote:
I've rewritten the speech-dispatcher pulseaudio driver, based on Lukes
libio driver and what I saw in the ao source.  My new pulseaudio
driver is only 177 lines, or about 1/10th of the old one.  It uses the
pulseaudio "simple" interface, just like libao.

The reason wrote this has to do with how ao sets up default buffering
parameters.  By default, pulseaudio buffers up to two seconds of audio
before beginning to play.  This is fine for playing music, but a
disaster for a screen reader, where key echos are often too short to
cause pulseaudio to start playing.  Unfortunately, the ao library is
meant to be simple, and doesn't have low-level controls on things like
how buffering works.  So, I rewrote pulse.c to link directly to the
pulseaudio "simple" interface, where I was able to properly set
buffering parameters for use with speech-dispatcher.

I think this should become the default speech-dispatcher driver for
Vinux/Lucid.  I've attached the pulse.c file, which should replace
src/audio/pulse.c.  If you get a chance to test it, please let me know
how it performs.  I know of no bugs when used with espeak for now.

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