25 March 2014
By Paul Divall, Managing Director: Broadcast and
Managed Solutions, Jasco
Ultra
High Definition (UHD) is here and it is beautiful. At 2160p compared to Full HD’s
1080p – that’s roughly four times the amount of pixels and 60 frames per
second, not 24 -- it’s a “see it to believe it” kind of experience. And to make
the experience fully immersive, UHD also brings us 24-channel sound, the
ability to browse and run applications (NetFlix, Pandora, etc) while you watch.
Is it a good buy right now though? It depends on what you are looking for.
Ultra
HD screens are relatively expensive: a 55-inch UHD TV costs about R60 000,
a 65-inch R90 000 and a 86-inch over R175 000. Unless you have money
to burn and are a videophile, the time may not be quite right. If you do buy, you
may not be able to enjoy all those pixels fully just yet. While standard and HD
grade visuals can be up-scaled for viewing on a UHD screen, the UHD content
production line is in its infancy and broadcasters are unlikely to offer UHD
channels for some time.
While
there are cameras available that are capable of recording UHD footage at 60fps
at resolutions of 3840 × 2160 (8.3 megapixels) for 4K UHD, this puts a lot of
pressure on storage capability - try 4TB of data for 20 minutes of footage. It
makes sense for professionals to use the best cameras they can and capture
footage in the highest resolution possible to ensure the longevity of their
material since the digital images can be downscaled to HD or even standard
definition. However, they will need to adapt their capture and store
strategies.
For
the consumer, there is another challenge. At present, it will take serious
compression to put a UHD quality movie onto any kind of easily portable
physical storage. Consider that a high-capacity Blu-ray disc in BDXL format holds
128GB. Sony and Panasonic are currently teaming up to develop a 300GB disc by
2015, but this is still not enough to hold a full length UHD movie.
Similarly,
streaming UHD format movies would require at least 15Mbps throughput, even at 24fps
compression rates. You would need fibre optic grade throughput to the house to
stream full UHD. In South Africa, many are lucky to get 2-4Mbps, putting this
out of our reach for now.
And
what about broadcasting? At present, an HD channel takes up four times the
bandwidth of a standard broadcast. A UHD channel would take many times more
than that, demanding a new standard in compression. In addition, decoders would
require a new chipset and software to decode UHD. With High Efficiency Video Coding (HEVC),
a new video compression format, only just broadly accepted (October
2013), it’s fair to say UHD broadcasting is in its infancy globally. HEVC is essentially expected to double data compression
ratios to provide better video quality at a low bit rate. It will support
resolutions up to 8192x4320 (8K).
So will you buy into UHD? HD technology in South Africa has
over the past decade seen fair adoption, with HD taking about 20 percent of the
market. UHD is likely to take only 1 or 2 percent of that market in the near
future. For consumers, the cost/benefit equation may not yet make sense when it
comes to buying a UHD TV. For professionals in the film and video production
industry, however, the time may be right – their new investments should
certainly support 4K. 4K UHD cameras are being launched with reasonable price
tags. With the right equipment, professionals can futureproof, or at least
extend the longevity of their outputs.
As to where the future of visual display may lead, perhaps
the only constraint in the future will be the size of your front door and, to
some extent, the size of your wallet.