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

Just managed to get this working and, wow, it's very fast. Looking forward to installing it on my netbook to see just how much faster I'll perceive that to run. It's already somewhat slower, and speech latency makes it seem more sluggish than it actually is.

I was pretty happy with the latency I received with the original patch, but I tried dropping the below #define to 32. It's even faster now. :) Might be worth giving this change a bit more testing and, assuming no one else reports problems with it, making it the default. Even if the original works better than any other Pulse solution out there, I doubt anyone would mind if it worked even better. :)

Thanks for this.

On 12/17/2009 09:23 AM, Marco Skambraks wrote:
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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