name Opus has been visible of late in codec circles, and Tieline has been a
particular proponent, adding the Opus codec to its arsenal of algorithms last
December. I asked Charlie Gawley, VP of sales for Tieline, to give us a bit
more background on it.
Gawley: Opus incorporates
technology from the well-known SILK and CELT codecs to create a low-latency
speech and audio codec. It is a variable bit-rate algorithm ideal for live
broadcast situations because of its capacity to deliver high quality, real-time
Audio over IP (AoIP) at low bit-rates and equally extremely low delay 2.5 ms at
higher bit rates.
As an example, if we look at G.711, a
1970s codec, and the latest in coding the “Opus” codec. In listening tests,
there was imperceptible difference between G.711 transmitting 64 kbps telephony
audio and Opus at approximately 10 kbps. Even more interesting with blind
listening tests it outperformed AAC ELD. So when we look at it from two
perspectives it takes six times less data to transmit with providing the same
quality and it provides better quality.
So why did we
adopt it? Tieline has always been at the forefront for delivering innovative
broadcast solutions, and we are the first to enable broadcasters to use Opus.
With its ultra low delay, low bit rate and high audio quality, we see Opus as
being a game changer for the industry just like MP3 did in the ’90s.
Following the validation of Opus by the EBU not long after it
being ratified by the IETF in September last year, we were approached by a
number of large European broadcasters requesting that we integrate Opus into
our hardware codecs, as they have recognized as we did the exceptional
qualities of this new codec. We also decided to implement it in ReportIT our
unrivalled smartphone codec for remotes on iOS and Android in terms or quality,
delay and, most importantly, stability.
The Opus website
includes graphics depicting the promised benefits.
“StreamGuys Adds Ogg Opus”