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

cool feedback - thanks
if you want to try different settings for latency etc.
you can change the define in speechd/src/audio/libao.c
#define AO_SEND_BYTES 256

if you reduce this value 128,64,32 ... and re-compile speechd
you can generate a faster resonse play/stop

the reason for me to create the patch was the alsa echo problem
if speech-dispatcher gets new strings very rapidly
the sound-output was a kind of a mixed speech output
sounds lke an echo
with libao and alsa there is no echo anymore :-)

happy testing


On Thu, 17 Dec 2009, Hammer Attila wrote:

Dear List,

Halim, this driver is fantastic my machine.
I tested the new driver.
Before with this testing driver is publicated, Pulseaudio doing 2-3 second latency when Speech-dispatcher is running in Ubuntu Karmic my notebook sound card and my desktop computer sound card.

I need remove Pulseaudio and coming back with alsa and do lot of workarounds to solving problems (volume increase/decrease workaround with custom keybinding command with amixer, remove unneed pulseaudio packages if I would like listen musics, videos etc).

Now when I testing the new driver, I am try the driver with Ubuntu Lucid system.

What can I see after when all required steps I doing the driver installation?
I get back my fast speech navigation when Pulseaudio is running my notebook.
Only a very minimal latency I see when I typing, but this is not matter (not 3 second latency). :-):-) Alsa is possible very little faster. But the new testing driver is very stable. Tomorrow I testing longest time.

What can I do when I would like compile and install the new driver?
Halim and me wroted 2 or 3 priwate letter, final, following simple method is working my machine. Note: Please, ewerybody try this method with only your risk! Important, following method working with Karmic and Lucid only. Halim, if I any step writing incorrect, please complete. Excuse me my bad english:

1. In Lucid, I downloaded speech-dispatcher source code from following command with a directory:
sudo apt-get source speech-dispatcher

2. Please do following commands:
sudo apt-get install libao-dev (this is important)
sudo apt-get build-dep speech-dispatcher

3. I navigate the speech-dispatcher source directory.

4. Applyed the new patch:
patch -p1 <../speechd-libao.diff
Please replace the patch path if you storing Halim sent diff file with another place. :-):-)

5. I run dpkg-buildpackage command.

6. I installed with following packages with prewious directory (need do a sudo cd .. command):
speech-dispatcher, python-speechd, libspeechd2.
Possible your system needs another packages, but you found with rebuilded packages with your needs. Possible the version number is change with your system.

7. I change the /etc/libao.conf with default_driver=alsa to default_driver=pulse.

8. Final, reconfiguring speech-dispatcher with using libao audio output module. Don't worry, my machine spd-conf ask me the suggested way is Alsa, Pulse, Oss, but don't need correct your answer. :-):-)

Enjoy, the new driver working my machine.

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