The DVB has given itself a new mission on behalf of the broadcast industry – preparing for the inevitable transition from broadcasting to streaming and creating a standards-based, best-of-breed ecosystem for the delivery and presentation of something that looks like television in that environment. If you want a simple analogy, think DVB-T for the post-broadcast age.
At IBC this year the standards forming organisation, which drove the analogue-to-digital transition in Europe, showed the world its starting point. It demonstrated a multi-vendor solution that combined the new DVB-I media layer and service discovery specification (including a DVB-I Service List) with DVB-defined approaches to multicast ABR (mABR), and low-latency streaming with DASH (the forthcoming LL-DASH standard).
A dozen DVB members were involved in what was a world-first demonstration of this next-generation television delivery ecosystem. These were ATEME, Broadpeak, ENENSYS Technologies, Harmonic, ITV, Kineton, Newtec, RAI, Rohde & Schwarz, SES, TPV Technology and ViaccessOrca.
The demonstration used two client (receive) devices, the first featuring an Android TV environment (or to be precise, an Android mobile client that had been ported to television). The second client was running an HbbTV application. These clients discovered the streaming services they needed using DVB service information and were delivered DVB-DASH unicast streams (DVB-DASH builds on the MPEG-DASH adaptive bit rate streaming standard with additional requirements to improve interoperability and help implementation).
The clients then switched seamlessly to a shared multicast ABR stream, thus halving the total bandwidth used. Low-latency was demonstrated at the same time, with a three-second delay evident. Crucially, the key technology pieces in the delivery chain, like encoder, server and client, were made by different companies.
The technical specs have already been approved for LL-DASH and the DVB-mABR specification will be ready by February. By the end of this year, the DVB will unveil a proof of concept for this Internet-era TV delivery solution, with 100 services running on it.
Although there are mobile clients that accommodate the DVB-I specification, the main focus of this initiative today is streaming to the television set. And while the demonstration at IBC covered live streaming, where the DVB has focused its efforts until now, Peter MacAvock, Chair of the DVB, said the next step will be taking the DVB-I concept into the on-demand universe.
DVB-I differs from HbbTV, the hybrid broadcast broadband standard that is widely supported by European broadcasters, in one crucial respect. Whereas HbbTV is a broadcast-first concept that enables the seamless incorporation of IP-delivered applications, DVB-I takes an IP-first approach. In fact, it is envisaged as an IP-only solution in the long-term.
The distinctions are not clear cut, though. The DVB and the HbbTV group are working closely on applications that will run over both standards, and many of the DVB-I concepts are being built into HbbTV.
DVB-I features include integrated channel lists, interactive content guides and simple lean-back channel selection. It means streaming services can be presented more like broadcast television today, like in a programme guide, with up-down remote control navigation and without the need for an app, although it can also be harnessed within apps (where the specification could be used for sub-UX layer activities).
The second key part of the IBC showcase was multicast ABR, which has the potential to solve the capacity issues for live streaming. mABR means that if one person is watching a linear/live video stream and others then request the same content, they will join the same stream. Effectively, unicasting is replaced with something that looks a lot like broadcasting – the chief benefit being that bandwidth remains steady no matter how many people are watching.
The DVB is creating standards-based interoperability for mABR that allows different manufacturers to make the server, the client and the encoder, giving vendor choice to service providers. The DVB believes this approach, which contrasts with end-to-end single vendor solutions, will be welcomed by the market.
The DVB has been struggling to find a role for itself in recent years and even held an inconclusive, public ‘What are we for’ debate at one recent IBC. But this year was a very different story.
The organisation is working on the basis that terrestrial broadcasting will become extinct in Europe in the years after 2030, by which point streaming over fibre or HFC will be the dominant method of delivery. It believes that the current approach to streaming will not suit the broadcaster community as they come to rely on it. The delivery chain is too proprietary and there is not enough interoperability between the key technologies, it argues.
“There is a cry from the industry, ‘Please, let’s standardise some of these elements so we can have a more economic solution across all the different platforms,” MacAvock says.
The DVB used its IBC showcase to test sentiment in the marketplace, given that there are viable solutions for streaming (regardless of any flaws). The feedback was positive.
MacAvock cannot say whether DVB-I will get the kind of backing that DVB-T enjoyed. “It is a more crowded marketplace and we are not the only game in town,” he admits. “But this has landed very well with broadcasters who are thinking about a future beyond broadcast distribution. The impression we were given is that we are on time, or slightly ahead of time, with what they need.”
The DVB is confident that broadcasters will support DVB-I for service discovery and not view it as a threat to their app empires. Currently, they can expand the content contained in their app, draw us into their world and hope to keep us there for longer than they might on a TV channel, which is so easy to navigate into and out of.
But apps come with pain – the need to create different apps for different environments, and there is a limit to how many devices most broadcasters can afford to get on. Dedicated apps, even for the largest broadcasters with the deepest pockets, cannot reach every consumer and DVB-I offers the enticing prospect of being able to stream to every device without dedicated integrations.
Of the IBC demonstration, MacAvock says: “This was our first toe in the water, showing how we replicate the DTT experience on a fibre connection, first in a hybrid broadcast broadband environment and then in broadband only.” Within the next year the specifications will be mature enough to implement, and we will know then what the real support is for the initiative, MacAvock forecast.
The technologies on the DVB stand represent a viable, working solution today but the standards-making organisation stressed that this is just a start and they are “absolutely not the finished product”. And now that you can develop specifications in software and do not have to lock your standard into silicon, developments can happen faster than they used to, of course.
Highlighting macro-trends that could increase demand for DVB-I, MacAvock noted that terrestrial spectrum is becoming scarcer and the requirements to access it are becoming harder. The television industry is in the process of a managed transition from full broadcast to a point where IP is the primary delivery mechanism. “That is a more significant change than we have ever seen before – more than the transfer from analogue to digital,” he points out.
At IBC, the DVB was showing what it believes television will look like when it is only delivered via the Internet. The combination of media layer, service discovery paradigms, multicast ABR and low-latency amount to a next-generation TV delivery solution. Whether this collection of standardised technologies gets the same backing as the preceding broadcast standards, like DVB-T, remains to be seen. But the technical offer is a DVB-T for the Internet era, if the market wants it.