aRts in trunk

Gary Cramblitt garycramblitt at comcast.net
Fri Jul 29 22:32:53 BST 2005


On Friday 29 July 2005 10:14 am, Scott Wheeler wrote:
> Coolo asked me earlier about the fate of aRts in trunk (which just switched
> over to KDE 4).  I suggested at this point that I didn't see any reason to
> keep a copy there; there's essentially no work being done on it and we plan
> on dropping it as a dependancy in KDE 4.
>
> Does anyone have an objection to aRts being removed from trunk?  If not
> I'll give him the "ok" in the next day or so.

By way of feedback, let me tell you of the current state of sound support in 
the KDE Text-to-Speech System (KTTS).  KTTS currently supports 4 audio 
plugins.  aRts is the only one which is fully satisfactory.  Here are the 
problems with the other 3:

1.  ALSA.  Problems with device contention.  Some users are unable to open 
multiple PCMs.  It appears this is a configuration problem with dmix 
compounded by terrible documentation on the ALSA website (The dmix wiki talks 
about OSS emulation.  Why must I deal with OSS emulation if I'm trying to 
solve PCM mixing problems?)  If your sound card has hardware mixing, you 
generally don't have a problem.  If not, there's a good chance you'll have 
this problem.  If anyone can shed better light on this problem, I'd be 
grateful.  My system doesn't exhibit the problem (my soundcard has hardware 
mixing), but lots of users have reported it.  (I am also seeing some things 
that suggest threads and alsalib don't get along but haven't been able to 
fully put my finger on the problem.  It doesn't help that the ALSA 
documentation is pretty poor.)

2.  aKode.  aKode does not offer a true pause() function.  The net result in 
KTTS is you must let the current sentence finish speaking when attempting to 
pause.  I realize aKode's primary purpose is decoding, not playback, but I 
mention this anyway.  See wish #107135.

3.  GStreamer.  As of GStreamer 0.8.10, it still can take up to a second for 
sound to stop playing when pausing or stopping.  Versions of GStreamer prior 
to 0.8.7 had major issues playing .wav files.  I still haven't figured out a 
reliable way to detect the minimum version of GStreamer in configure.in.in, 
since the core library is 0.8.7, but the wav plugins are 0.8.5.  Any help 
from autoconf/GStreamer experts would be welcome.   GStreamer with the alsa 
sink also exhibits PCM contention problems; probably ALSA config problem 
again.

I understand that aRts is unsupported, nobody wants to do the maintenance (I 
certainly don't have the expertise or time), and getting rid of it in KDE 4 
is desirable.  My concern is that I'll be left with no good solution, when 
all is said and done.

-- 
Gary Cramblitt (aka PhantomsDad)
KDE Text-to-Speech Maintainer
http://accessibility.kde.org/developer/kttsd/index.php



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