Delivering high resolution live television
By Karl So, Caton Technology
Broadcasters in many parts of the world are now promoting 4k Ultra HD. They use it as a market advantage, a differentiator which audiences recognise and which boosts viewing figures and potentially revenue.
In Japan and China, 8k Ultra HD is now on air. Receivers are readily available across the Far East, at price points equivalent to around US$5000. According to researchers Strategy Analytics, one million 8k televisions were sold globally in 2021. The forecasters predict that about 72 million households worldwide will have an 8k receiver in 2025, although to put this in context there are 1.7 billion homes with television in the world.
Ultra HD – 4k and particularly 8k – is seen as a premium service, something that is reserved for key content where it will make the most impact. Japanese broadcaster NHK produced 200 hours of 8k video during the Summer Olympics in Tokyo held in 2021, and a Chinese broadcaster went live with 8k for the Beijing Winter Olympics earlier this year.
The FIFA World Cup, to be held in Qatar late in 2022, will be covered in 4k throughout, with some additional 8k shoots for key games. The BBC coverage of this year’s Glastonbury Music Festival was in 4k Ultra HD from the Pyramid Stage.
All these and more are high profile, live events, where absolute security of delivery and superior quality is essential. The challenge for engineers is to get the signals from the venue to the rights-holding broadcasters, wherever they are.
With the best HEVC encoding available, contribution quality 4k demands a minimum of 50 Mb/s. Add in ancillary services and overheads and you need 60 – 70 Mb/s to be sure. A leased line with that capacity would probably cost around $100k to establish plus a hefty monthly rental. And you would probably want two geographically diverse routes for redundancy, doubling the cost.
Satellite capacity, if available, is priced at around $1500 per megabit per month, so again in the $90 – 100k region. But satellite capacity is constrained, not least because the spectrum for C-band satellites is being taken over by 5G (and future 6G) cellular services.
These numbers are for 4k Ultra HD. The situation for 8k is more complex because there is no finalised and agreed codec. VVC/H.266 is currently in development, but it could be five years before there are production chips to do it. At the moment there are a handful of hand-crafted coders and decoders in the world: the services at the Beijing Olympics used these rare resources at a reported 85 Mb/s.
For practical 8k contribution circuits today, the solution is to split the signal into four quadrants and treat it as four 4k streams. We need H.266 to be standardised as soon as possible!
What is clear from this analysis is that delivering Ultra HD on contribution-quality circuits is a very expensive business. The pressure is on to find a way to cut costs as live productions become a routine matter.
We see the solution as a format-agnostic transport layer built on the public internet, for at least part of the circuit. But, as we are all aware, the internet is far from deterministic, so any scheme has to build in extensive protections to deliver the security broadcasters expect.
This is why we developed the Caton Transport Protocols (CTP). These implement more than 30 algorithms, including machine and deep learning approaches, along with our unique dynamic forward error correction. Security is guaranteed through AES-265 encryption. CTP is designed for high quality, low latency contribution video at scale, over any IP network, including the public internet as needed.
To this we add the Caton Video Platform (CVP), ultra-low latency, high availability dedicated interconnectivity network with points of presence in more than 60 countries worldwide. Together, we package the video stream, in any format (including NDI for dynamic production) into CTP, route it over the public internet or locally available circuits to the nearest point of presence, then deliver it to one or many remote points and, if necessary, over local circuits again to the destination.
Users have access to management tools to establish and monitor the connection, and routinely expect up to five nines stream availability, secured end to end. This is provided at significant cost savings over “traditional” routing – 50% or more – and is available as required, rather than subject to expensive minimum rentals. If you only need the circuit for three hours, why pay for a month?
Broadcasters around the world now see 4k Ultra HD over CTP and CVP as routine. We first demonstrated 8k more than two years ago, and we have delivered circuits, to our high standards, as our users have requested them.
Broadcasters want to deliver the best quality to their audiences, and to use new offerings like Ultra HD as a means of standing out in competitive markets. Budgets are always tight, while the prospect of black screens is what keeps chief engineers awake at nights.
CTP and CVP provide the SLA, the simplicity of use and the cost-effective solutions which allow broadcasters and production companies to unlock the full potential of IP connectivity, anywhere in the world.