Poor Voice Quality on Windows Mobile 6 (with Codecsother than G711)

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Thanks Benny, I will try to use latest SVN version which has WSOLA disabled to see if at least GSM works fine.

As I understand, PJSIP is using Speex 1.2 Beta 1 version. Is there any work going on for incorporating latest version 1.2 Beta 3 of Speex into PJSIP which may give much better performance as the basic Speex Codec library has been separated out of non-codec components and can be built without Floating point support. FPU is missing in Win CE which may have been a significant factor in its poor performance on mobile.

~Girish

-----Original Message-----
From: pjsip-bounces@xxxxxxxxxxxxxxx [mailto:pjsip-bounces at lists.pjsip.org] On Behalf Of Benny Prijono
Sent: Thursday, April 24, 2008 6:09 PM
To: pjsip list
Subject: Re: Poor Voice Quality on Windows Mobile 6 (with Codecsother than G711)

On Thu, Apr 24, 2008 at 10:43 AM, girish_kumar <girish_kumar at infosys.com> wrote:
>
>
> Hi,
>
> We have built PJSIP for wince platform and deployed it on to Windows Mobile
> 6 based device without exploring any media optimizations.
>
> The Voice quality is fine with both variants of G.711 codec and CPU
> utilization is observed at around 50%. However, if try to use iLBC or Speex
> (Narrow-band) codecs, the voice quality drops drastically to an
> unrecognizable level and CPU utilization shoots into 90-100% range.
>

Hi Girish,

the CPU usage for G711 looks too much, it shouldn't be that high for
G711 IMO. If you're using relatively latest SVN version (the one with
WSOLA in it), please update again to the very latest SVN version. In
current SVN, WSOLA is disabled on both WinCE and Symbian (via
config_site_sample.h) since it seems that it's a bit too much for
these devices.

Having said that, I've never heard people successfully use Speex on
PDA/mobile devices. IMO Speex is just too demanding for these devices.
And probably iLBC is too. But GSM should work, and if you can afford
the bandwidth, G.722.


>
> Has anyone used PJSIP on Windows Mobile 6 and can verify if these
> observations on Voice quality are justified? Please suggest some
> optimizations to improve the quality of voice.
>
>
> Also, the Echo Cancellation is resulting in Jittery Voice (for G.711 codec)
> while Echo Suppression works fine. Any suggestions.
>

The EC is probably too much for mobile devices too, hence it's
disabled by default.

Cheers
 Benny


>
> Thanks
>
> Girish
>
>
> **************** CAUTION - Disclaimer *****************
>  This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended
> solely for the use of the addressee(s). If you are not the intended
> recipient, please notify the sender by e-mail and delete the original
> message. Further, you are not to copy, disclose, or distribute this e-mail
> or its contents to any other person and any such actions are unlawful. This
> e-mail may contain viruses. Infosys has taken every reasonable precaution to
> minimize this risk, but is not liable for any damage you may sustain as a
> result of any virus in this e-mail. You should carry out your own virus
> checks before opening the e-mail or attachment. Infosys reserves the right
> to monitor and review the content of all messages sent to or from this
> e-mail address. Messages sent to or from this e-mail address may be stored
> on the Infosys e-mail system.
>  ***INFOSYS******** End of Disclaimer ********INFOSYS***
>
> _______________________________________________
>  Visit our blog: http://blog.pjsip.org
>
>  pjsip mailing list
>  pjsip at lists.pjsip.org
>  http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org
>
>

_______________________________________________
Visit our blog: http://blog.pjsip.org

pjsip mailing list
pjsip at lists.pjsip.org
http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org



[Index of Archives]     [Asterisk Users]     [Asterisk App Development]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Security]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [Linux API]
  Powered by Linux