Speex dev - Sep 2005 - Speex and Builder

> Obviously this is Jean-Marc's decision and I'm not telling
> him not to support this compiler. I am however pointing 
> out that this compiler is yet more work for very little
> payoff. In the case of my project, the proponent of C++
> Builder sent me a huge, monsterously ugly and totally
> unmaintainable patch to add C++ Builder support. Needless
> to say, that patch was *not* applied.
Actually, it used to be that Speex would compile (with a few warnings)
with a C++ compiler. So I'm not against the idea of bringing that back,
as long as the modifications to do so are not too insane.

	Jean-Marc

-- 
Jean-Marc Valin <Jean-Marc.Valin@USherbrooke.ca>
Universit? de Sherbrooke

> 1) May I know how Speex compared with GIPS codec?  It seems that Google,
> Yahoo, and Skype are licensing from GIPS.  Are there any good benchmarking
> or fair comparisons?
I think these two emails sum up my opinion about Speex vs. iLBC:
http://lists.xiph.org/pipermail/speex-dev/2005-June/003410.html
http://lists.xiph.org/pipermail/speex-dev/2005-September/003652.html
> 2) In particular, how is the jitter buffer control for Speex in response to
> intermitent poor connection hiccups?  Is it robust enough to smooth out
lost
> packets (error concealment) and quick enough to recover the live
> conversation smoothly once the packets received are back to normalcy?
There is packet loss concealment in Speex even without using the jitter
buffer (no, error concealment wasn't invented by GIPS). As for the
jitter buffer itself, it's adaptive, so it just keeps the lowest
possible delay that doesn't cause losses.
> 3) Has anyone used Speex for live VoIP application?  Any good references or
> examples to start with? 
I've written a demo application for Linux that uses wideband, echo
cancellation, denoising and the jitter buffer. I'll post it soon.
> 4) Since we are focusing on the user application development, may I know
> what is the highest-level API for Speex that a developer can use such that
> all lower-level issues related to buffering, error concealment, codec, etc.
> are automatically taken care of?
There's only the Speex API, but I think it's simple enough that you
don't need a higher level API (at least not for VoIP).

	Jean-Marc

-- 
Jean-Marc Valin <Jean-Marc.Valin@USherbrooke.ca>
Universit? de Sherbrooke

Hi,

We are planning to use Speex as the speech codec for a VoIP application.

1) May I know how Speex compared with GIPS codec?  It seems that Google,
Yahoo, and Skype are licensing from GIPS.  Are there any good benchmarking
or fair comparisons?

2) In particular, how is the jitter buffer control for Speex in response to
intermitent poor connection hiccups?  Is it robust enough to smooth out lost
packets (error concealment) and quick enough to recover the live
conversation smoothly once the packets received are back to normalcy?

3) Has anyone used Speex for live VoIP application?  Any good references or
examples to start with? 

4) Since we are focusing on the user application development, may I know
what is the highest-level API for Speex that a developer can use such that
all lower-level issues related to buffering, error concealment, codec, etc.
are automatically taken care of?

Thanks,
Joe