Coming to a TV Set Near You: Artificial Intelligence
If it wasn’t clear to us before NAB 2015 started, then what Positive Flux would cover in this year’s NAB report was instantly apparent the minute we walked onto the show floor. From the banners outside the building to the booths of every major vendor and hundreds of smaller ones, the buzz was unmistakable:
Video over IP is not a concept that is in our distant future, but a technology that is coming very, very soon.
Before we explain what Video over IP is, let us tell you why we are excited. Video over IP relates to something Positive Flux has been saying for several years: the broadcast production/distribution model needs to become more flexible–in a hurry–if it is even going to just keep up with the rapid changes underway in the consumer electronics space. A consumer can already buy equipment for a reasonable price that exceeds the best quality and viewer experience than any traditional media company currently provides to the home.
We are talking about UHDTV (Ultra High Definition TV). Positive Flux believes that, unlike 3D, UHDTV is going to become attractive to consumers. This is because UHDTV supports HDR (High Dynamic Range), which provides significantly improved contrast between brights and darks and delivers the improved colorimetry supported by modern display devices. It is a difference consumers can see and respond to instantly. (Read our analysis at http://www.positiveflux.com/flux-reports-uhdtv/)
Video over IP is needed now because UHDTV requires at least four times the bandwidth of HDTV. This means that the signals being sent around production facilities, commercial insertion systems, and distribution paths today will not work with previous generations of equipment.
The higher bandwidth could be met by improvements in SDI (Serial Digital Interface Technology) over serial video cable and BNC connectors, but right now it takes four 3Gigabit/second HDSDI cables to connect just a single, full resolution UHDTV signal between devices. That’s not practical for many environments.
Improvements to SDI are coming. Devices with 6Gigabit per second interfaces are starting to be shipped and standards have been adopted for 12Gb/s SDI and higher. The catch is that speed increases for SDI historically have been linear. Nevertheless, companies like Genum are doing yeoman’s work pushing SDI technology forward and there has been extensive testing to show compatibility with existing cables and connectors. There is no doubt that there are those who feel passionate about the plug and play nature of SDI and it will remain a preference for some vendors and broadcast plants.
Figure 1: Commonly available bandwidth per single link, SDI vs Ethernet.
So, what is Video over IP?
Ethernet offers compelling benefits for the delivery of high-bandwidth signals that can’t be matched by SDI. Part of that development success has been driven by sheer scale–there are way more customers and money spent for network switches than there ever has been for broadcast routers. The IT industry has responded with logarithmic improvements in the speed capacity of Ethernet, versus the linear improvements for SDI. Ethernet also offers flexibility. Putting video signals on an Ethernet connection via an RJ-45 connector means that a variety of signals could eventually go on the same cable. Video over IP will let us reduce connectivity and switching costs while simultaneously opening up tremendous opportunities to take advantage of the more rapid pace of innovation in the computer industry.
Of course it is not as simple as just switching to computer networking technologies. Every frame of a television signal needs to be re-created in order and cannot be skipped. Computer networks are notoriously bad at this because they are not designed for such “deterministic” delivery, but some exceptionally clever work is being done to keep the timing correct and to permit clean switching of the streams at the end point. One example, and a highlight of NAB 2015, was a UHDTV mobile unit made by GameCreek using Video over IP for connectivity. It’s a very good start for the Video over IP path.
Haven’t we seen this movie before?
As far back as fifteen years ago we saw the beginning of digital audio networks and AoE (audio over Ethernet). This technology remains powerful and, in theory, hundreds or thousands of audio signals can be sent over a single network cable. But adoption has been erratic, mainly because there are so many incompatible standards. MADI (Multichannel Audio Digital Interface, or AES10) is over twenty years old and is considered the most mature and reliable, but it does not use Cat-5 connections, is point to point, cannot be switched and does not carry any informative data. There are scores of other standards, seemingly one for each manufacturer. Early attempts at more flexible networking included CobraNet and EtherSound from the 1990s. Newer technologies such as DANTE (developed in 2006 by Audinate) and RAVENNA (2010, open standard) can be routed over modern networks, but they are not only incompatible with each other, they seem to be at war. (If you are lover of history or literature you will know Ravenna was the city in which the famous poet Dante died.) Luckily the AES (Audio Engineering Society) has begun the peace process with their (2013) standard AES67, so industry-wide adoption may become possible in the future.
SMPTE to the rescue
Video over IP could be hampered by similar conflicts and incompatible formats that have confounded the audio industry unless our vendors take measures to avoid those problems. The truth is that early implementations are largely incompatible. This happened because several forward-looking vendors anticipated the pivot point we illustrated above and began development long-before standards were available. We are now seeing efforts to connect those systems to equipment from other vendors. SMPTE has released a number of standards including SMPTE-2022 (switching) and SMPTE-2059 (Timing and Synchronization) which lay the groundwork for compatibility.
There’s still significant work to be done, but we can see that a future utilizing Video over IP is in sight. In conversations during NAB 2015 with the CTO of a major switcher vendor Positive Flux asked if that company’s next generation of behemoth live production switcher will have BNC connectors, RJ-45s, or a choice of either. His answer was very revealing. Let’s just say that they believe in Video over IP.