
High-definition audio cell phone system deployed in Moldova - rms
http://www.forbes.com/forbes/2009/1116/technology-cellular-wireless-get-ready-for-hi-def.html
======
chrisbolt
12 kilobits per second is high definition?

~~~
nitrogen
In the voice world, they call anything above an 8kHz sampling rate "HD audio."
It's the next big thing in voice conferencing: 16kHz sampling rate! The
comfort noise (noise played by a phone so you know it hasn't disconnected)
never sounded so clear! Naturally, it's all patented and proprietary.
Meanwhile there are open source systems capable of CD quality audio at speech
latencies (<http://www.celt-codec.org/>), but why use that when you can pay
for an AMR-WB license?

Actually, I set up an Asterisk PBX once for a demonstration of an HD voice
system with a 48kHz/24-bit AEC system that was shown at Infocomm, and it does
sound nice.

~~~
DarkShikari
_CD quality audio at speech latencies_

Don't exaggerate so much. Celt is good, but it's not magic. It certainly won't
even be as good as something like AAC-HE -- which of course is intentional,
since Celt's target is ultra-low-latency situations, which inherently results
in worse compression. It also has to be relatively loss-redundant without the
use of forward error correction, which introduces even more constraints on
inter-frame prediction.

And of course one may note from <http://www.celt-codec.org/comparison/> that
it doesn't actually compete with AMR; it's easily 5-10 times lower latency
(and higher bitrate as well). It's really just a totally different use-case.

 _proprietary_

However crappy it is, I'm pretty sure I recall AMR being an open 3GPP spec.
There's even a free software implementation (under Apache v2).

~~~
ZeroGravitas
The CELT developers themselves say _"CELT brings CD-quality sound to VoIP-
style low-delay applications"_ but it would be easy to get into an argument
about what "CD-quality" means.

On another note, as the other poster stated, AMR is patented. Not everyone
includes that in their own personal definition of "proprietary", but the two
words are synonyms.

~~~
DarkShikari
If being covered by software patents made something proprietary, the entire
world would be proprietary, nearly every single open source project included.

~~~
ZeroGravitas
After I wrote that I recognised the ambiguity and I was going to go back and
edit it to say something like "actively enforced patents to generate licence
fees", but I thought it was obvious enough as it was, given the context.

~~~
DarkShikari
I still don't like that definition, since it confuses the vast majority of
multimedia formats with formats that are actually proprietary.

I prefer to reserve the word proprietary for formats where the specification
is either secret or does not exist and any free implementations were reverse-
engineered, e.g. RealVideo, Windows Media Audio, and so forth.

It doesn't make sense IMO to simply call 98% of everything proprietary; it
sort of weakens the meaning of the word to overuse it as such.

