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Re: SourceForge CVS




For the record, the alsa config code in the emacspeak server is
taken from the examples that are in the doxygen directory of
alsa-lib --- so any bugs there are not mine but directly
descended from Alsa

>>>>> "Lukas" == Lukas Loehrer <listaddr1@gmx.net> writes:
    Lukas> Hi Tim, A utility for checking out card parameters
    Lukas> will certainly be useful to many peaple here.
    Lukas> 
    Lukas> I believe that the apparently superfluous tests in
    Lukas> alsa_configure are to do automatic parameter selection
    Lukas> by default and if that fails, the user can initialize
    Lukas> some of the variables to a non-zero value and the
    Lukas> automatic setting will be skipped. The use of the
    Lukas> snd_pcm_get_period_time function in the place it is
    Lukas> currently used is most likely a bug however.
    Lukas> 
    Lukas> I also have one machine where the period size is by
    Lukas> default 16, which is far too low for a buffer size for
    Lukas> the eci callback (chunk_size). Choosing chunk_size as
    Lukas> a multiple of the cards period size and about a
    Lukas> quarter of the alsa buffer size has given me good
    Lukas> results. As we ar using interlieaved mode, I believe
    Lukas> that the actual value of the period size is not that
    Lukas> important.
    Lukas> 
    Lukas> By the way, I believe that most crashes I see are due
    Lukas> to bugs in the ViaVoice speech synthesis code. I have
    Lukas> been recording the communication between emacspeak and
    Lukas> outloud to see what could trigger the crashes but have
    Lukas> not yet been able to draw any meaningful conclusions.
    Lukas> 
    Lukas> Best regards, Lukas
    Lukas> 
    >> Hi Lukas, > >
    Lukas> Thanks for that, you saved me a bit of time. In fact,
    Lukas> after a little > thought and a bit of judicious
    Lukas> scanning of the alsa docs (I'm new to > alsa), plus a
    Lukas> little very simple utility program I wrote to dump out
    Lukas> > my cards hw parameters, I've managed to get things
    Lukas> working really well
    >> in just over an hours work over lunch.  > > Here is what
    >> I've
    Lukas> discovered: > > The snd_pcm_hw_params_get_buffer_time
    Lukas> will work if you have saved your > earlier settings
    Lukas> prior to calling it. I believe what is happening is >
    Lukas> that once you have selected the mode, format, rate
    Lukas> etc, then the call > will work. I guess by the time
    Lukas> you have selected the other parameters, > the possible
    Lukas> buffer size choices have been constrained enough for
    Lukas> the > function to identify a specific size.  >
    >> I guess we could do one of two things. Put a call to set
    >> the >
    Lukas> parameters prior to calling this function or test the
    Lukas> return code from
    >> snd_pcm_hw_params_get_buffer_time and if its less than 0
    >> then call >
    Lukas> snd_pcm_hw_params_get_buffer_time_max. The problem
    Lukas> with the second > solution, as you pointed out, is
    Lukas> that you may end up with an overly > large buffer and
    Lukas> get underruns etc. However, I did notice the result >
    Lukas> from calling the function after having set and saved
    Lukas> the earlier > values seems very small (16), especially
    Lukas> when compared tot he max value.  > > Something I did
    Lukas> notice when looking at the code is there are a couple
    Lukas> > of if statements which don't appear to be really
    Lukas> doing anything - I'm > guessing they are an artifact
    Lukas> from when Raman was developing the code.  > For
    Lukas> example > > if (buffer_time == 0 && buffer_frames ==
    Lukas> 0) { > > both buffer_time and buffer_frames are
    Lukas> initialized to 0 and this is > the first time they are
    Lukas> referenced, so the test is always true. I've > not
    Lukas> removed them yet, but unless I'm missing something,
    Lukas> there doesn't > seem to be any reason for them to be
    Lukas> there.  > > I wrote a very simple utility which dumps
    Lukas> out my cards hardware > settings. Using the values
    Lukas> from this, I created a new .asoundrc file > which
    Lukas> appears to have fixed all my underrun problems. I'm
    Lukas> going to > clean it up a bit and send it to the list
    Lukas> just in case someone else > finds it useful.  > > One
    Lukas> very good thing about the new atcleci.cpp code is that
    Lukas> it seems *a > lot* more stable. In fact, rather than
    Lukas> the server dying every few > minutes, it has not died
    Lukas> for me in nearly an hour so far. I'm thinking > this
    Lukas> could be due to your suggested additions to add the
    Lukas> functions to > free up resources correctly - the
    Lukas> crashes could have been due to > resource
    Lukas> limitations. At any rate, its working remarkably well
    Lukas> now.  >
    >> Another interesting discovery I made is that the ViaVoice
    >> eci.ini
    Lukas> file > appears to be slightly different in current
    Lukas> versions than the older > one. I decided to generate a
    Lukas> new one using the initgen utility just to > check
    Lukas> there had been no changes in later versions of
    Lukas> ViaVoice. The one > generated by initgen has some
    Lukas> extra header fields not in the original > i.e.  > >
    Lukas> [1.1] > Path=/opt/IBM/ibmtts/lib/eng50.so >
    Lukas> Version=5.0 > Concatenative=1.0 > CallbackFlag=0x3f >
    Lukas> ...  > ...  > > regards, > > Tim > >
    Lukas> -----------------------------------------------------------------------------
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    >> "unsubscribe" or "help" >
    Lukas> 
    Lukas> -----------------------------------------------------------------------------
    Lukas> To unsubscribe from the emacspeak list or change your
    Lukas> address on the emacspeak list send mail to
    Lukas> "emacspeak-request@cs.vassar.edu" with a subject of
    Lukas> "unsubscribe" or "help"

-- 
Best Regards,
--raman

      
Email:  raman@users.sf.net
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