With AV still trying to decide what compression levels are best, Hurrairah bin Sohail finds out how QVC studios in Tokyo, Japan have moved to uncompressed 4K transmission over IP.
The appearance of 4K on the tech landscape has caused significant disruption. Higher resolutions mean that larger amounts of data
need to be transmitted from one point to the other.
Without an accompanying shift to higher bandwidth IP networks, 4K video content transmission requires the use of compression. At present, this is the exact solution that the AV industry is providing with a range of different products based on different codecs battling it out in the market.
However, compression has always been regarded as a dirty word among purists. Does
the technology to transmit uncompressed 4K video signals exist and is it ready to be put to use and deployed?
These were exactly the questions that QVC, an American broadcaster, wanted answers to.
As an organisation, QVC made the decision to start broadcasting completely in 4K resolution.
Its studios in Tokyo, Japan were to serve as the first test-bed for QVC’s efforts with its other operational locations to follow suite. To help with the project, American integrator Diversified was brought on.
Jay Park, director of international projects at Diversified, talks about the collaboration between the client and the integrator: “From the start, we knew that QVC wanted to shift to 4K video broadcast and that the client did not want to use compression. Quality was the key criteria for QVC. Luckily, QVC has an extremely strong engineering team and we also have a strong design team with previous IP experience. We both put our heads together and started to work on how to make QVC’s requirements come to be
at its studio in Tokyo.”
Park continues: “Our task was
complicated by the fact that the broadcast industry had yet to catch up with what we wanted to achieve. Manufacturers
were building products for the transmission of uncompressed 4K video but some were in the testing phase and some were not ready. The industry itself was still working and deciding on the standards that would make this possible so getting these different products to work together was also a challenge.”
At the NAB 2018 exhibition, SMPTE introduced the ST 2110 professional media over managed IP networks suite of standard. This was a major step towards a common internet protocol-based mechanism
for the broadcast industry
and enabled the transport of synchronous 4K video signals over asynchronous IP networks.
The introduction of the ST 2110 standard guided QVC’s and Diversified’s decision to opt for IP network based transmission. Park details: “With the introduction of ST 2110 we had
a framework which could be implemented and this led us to choose the IP solution.”
With IP networks being selected for 4K video, QVC
made a significant investment
to make sure that the network infrastructure was up to scratch to handle the traffic. The network topology features an Arista 100Gb network switch at its core while 25Gb Arista network switches are used at the edge for transporting uncompressed 4K video signals and 10Gb Arista network switches are employed for transporting uncompressed HD video signals.
Grass Valley Vision Mixer units serve as switchers for the broadcast equipment and reduce the complexity of production workloads with support for multi-format production.
As Diversified proceeded with integrating the systems for QVC, the integrator came across an interesting puzzle. Park explains: “The backbone of the broadcast system is the IP network. But a lot of broadcast equipment still uses copper for transmission. We needed a way to link these two
systems together.”
This puzzle was solved with the use of cross converters from copper to IP and vice versa.
The downstream kit for the broadcasts systems at QVC are based around the Harmonic Spectrum X media server system which is used for ingest and for the purpose of recording and playing content. Tektronix monitoring and Sony Up/ Down convertors also make up the downstream kit.
With this equipment an overall workflow for the uncompressed 4K video broadcast system at QVC begins to take shape. IP cameras are used to record video content which is fed directly into the Arista network switches. From here, the signals are sent
to the Imagine SNP units for conversion to copper so that
they can be fed to the Harmonic Spectrum X media servers and the larger downstream system.
At the end of the cycle, the signals are returned to the Arista network to be transmitted.
Blackbox KVM is used to manage the AV systems, AVID units are used for editing while EMC Islion units are used for storage.
Regarding the challenges faced by Diversified, Park says: “We were charting new waters with the
QVC project. Deploying an uncompressed 4K video signal transmission system over IP is something that was new to us. Designing the entire system was crucial. Moving on, integrating the different products together was also a challenge. We had to be extremely mindful of all the components and spent a lot of time de-bugging and making sure we were using the right firmware versions because there wasn’t a reference or a rulebook that we could easily consult.”
In conclusion, Park says: “In the broadcast world, we are not at
the stage where all installations select IP networks for signal transmission. It says something about the commitment of QVC to quality that it was willing to make the investment and take the leap to create an uncompressed 4K video system over IP.
“We learned a lot working
on this particular project. The deployment for the systems was different. Traditionally, you have all these patches and a tried and tested method of getting the systems up and running. But commissioning for QVC in Tokyo, Japan was almost entirely via programming. If you have this skill, it is much easier to deploy systems and troubleshoot them."