Broadcast Bridge
The Broadcast Bridge assesses how far UHD has come and finds
rollout hindered by being inextricably bound up with the complexities of High
Dynamic Range (HDR). The industry will be hoping for 4K consumer displays sales
to kick off with the UHD HDR broadcast of the FIFA World Cup from Russia this
summer.
“Many consumers have already got 4K TVs in their home, but
are often mainly watching upscaled HD, or even SD, content on it,” he adds. “Many
probably wouldn’t notice a significant difference in quality, as they don’t
necessarily understand picture heights away from the screen, and wouldn’t
necessarily get a huge display to make the difference obvious, but know they
have ‘the latest technology’.
While Sky and BT have launched successful UHD services
without HDR, there is general agreement that 4K needs to be a significant
visual improvement over the current technology (i.e. HD) for customers to pay
more for it.
“This is especially true on the production and professional
facility side of the equation – due to the need to upgrade equipment that can
handle the higher bandwidth required for baseband signals (~12Gbps),” says
Matthew Goldman, svp, Technology, Media Solutions, Ericsson. “Content
providers and operators have therefore been evaluating the ROI on delivering 4K
versus the benefit achieved, and this has delayed some deployments.”
But if, as seems the case, the investment in infrastructure
needed for HDR is relatively minor and can often be handled in the current
equipment, what’s the hold up?
“There are too many different HDR formats being touted,
causing industry confusion about how to proceed, which in turn has delayed
deployments,” says Goldman. “Industry requests and attempts to simplify
offerings (for example along the lines of a ‘grand alliance’ of proposals) have
largely gone unheeded.”
Broadcasters have had to pause to evaluate the merits and
market adoption of multiple HDR formats the leading trio being HDR10, HLG10,
PQ10/Dolby Vision, where 10 reflects 10 bits. It’s assumed that HDR bundles in
Wider Color Gamut/WCG).
“If there are too many formats to choose from, then it
becomes a content management headache, so just like codecs, broadcasters would
prefer fewer, or one, high performance version to work with,” agrees Green.
According to an IABM IBC 2017 survey, approximately 1/3 of
those responding had no intentions of launching UHD delivery, the responses
virtually unchanged from the same question at NAB 2017. Click to enlarge
When even your latest smartphone can shoot and record 4K the
industry must have reached some sort of tipping point. Yet 4K combined with HDR
has long been considered the ‘wow factor’ which will open up the
next-generation TV viewing experience. As such, there is pent up interest –
among broadcasters/producers/operators – to provide and deliver content in this
format, rather than just the higher resolution.
“4K UHD rollout is still in its infancy,” says Rob Green,
senior marketing manager, at Xilinx. “The camera sensor and display
technologies for 4K are readily available, the workflows in more advanced parts
of the world are capable of handling UHD. However, getting it to consumers,
while making money, is presenting a challenge to broadcasters.”
According to Ericsson’s ConsumerLab TV and Media Report 2017,
ownership of HD TVs has increased from around 75 percent in 2012 to almost 85
percent in 2017, and 4K/UHD TVs are now present in over a fifth of all homes.
Consumer demand for 4K content, and the ability for content
providers to somehow monetise that demand, are key. The creation of 4K content
does not appear an issue. A great deal of content is already being captured in
4K even though it doesn’t make it through the rest of the chain. A lot of
YouTube content is being created in 4K for instance, because of phone and
low-cost cameras capable of capturing it.
“Part of the issue holding back widespread 4K TV content
consumption is the encoding and reuse of existing transmission infrastructure,”
reckons Green. “HEVC/H.265 can enable this to some extent and new codecs are
appearing, but you need receivers (set tops and TVs) that can handle decoding,
which, particularly for set-tops, means investment with a clear ROI.
Consumers are buying new TVs with higher picture quality.
Ownership of HD TVs has increased from around 75 percent in 2012 to almost 85
percent in 2017, and 4K/UHD TVs are now resent in over a fifth of all homes.
Click to enlarge. Source: Ericsson, ConsumerLab TV and Media 2017.
“Many consumers have already got 4K TVs in their home, but
are often mainly watching upscaled HD, or even SD, content on it,” he adds.
“Many probably wouldn’t notice a significant difference in quality, as they
don’t necessarily understand picture heights away from the screen, and wouldn’t
necessarily get a huge display to make the difference obvious, but know they
have ‘the latest technology’.
While Sky and BT have launched successful UHD services
without HDR, there is general agreement that 4K needs to be a significant
visual improvement over the current technology (i.e. HD) for customers to pay
more for it.
“This is especially true on the production and professional
facility side of the equation – due to the need to upgrade equipment that can
handle the higher bandwidth required for baseband signals (~12Gbps),” says
Matthew Goldman, svp, Technology, Media Solutions, Ericsson. “Content providers
and operators have therefore been evaluating the ROI on delivering 4K versus
the benefit achieved, and this has delayed some deployments.”
But if, as seems the case, the investment in infrastructure
needed for HDR is relatively minor and can often be handled in the current
equipment, what’s the hold up?
“There are too many different HDR formats being touted,
causing industry confusion about how to proceed, which in turn has delayed
deployments,” says Goldman. “Industry requests and attempts to simplify
offerings (for example along the lines of a ‘grand alliance’ of proposals) have
largely gone unheeded.”
Broadcasters have had to pause to evaluate the merits and
market adoption of multiple HDR formats the leading trio being HDR10, HLG10,
PQ10/Dolby Vision, where 10 reflects 10 bits. It’s assumed that HDR bundles in
Wider Color Gamut/WCG).
“If there are too many formats to choose from, then it
becomes a content management headache, so just like codecs, broadcasters would
prefer fewer, or one, high performance version to work with,” agrees Green.
The ‘wow’ factor of HDR is undeniable and can be achieved by
delivering 1080p50/60 HDR as the UHD format and have the display upconvert
1080p to 2160p (4K). The reasoning for this is that at least for the
foreseeable future the screen sizes used in actual consumer viewing
environments are not large enough to resolve the 4K resolution at the distance
from which the screen is actually viewed.
“Some broadcasters are considering delivering content in
[this format] and if the display supports HDR, then the end result will have a
‘wow factor’ nearly identical to viewing native 4K HDR,” says Hoffman. “As
such, this alternative format is by far the ‘best bang for the bit’.”
With 4K already well-established in consumers' minds, the
next selling technology may be broadcaster-friendly HDR.
Recorded UHD content is increasing in availability. The
content producer will determine the native format and broadcasters (or any
intermediary service providers or operators) are able to perform offline
conversions as necessary. This removes much of the barrier caused by having too
many format options.
Yet this is not the case for live events, due to the need
for everything to work flawlessly in real-time. Including HDR in live is
additionally problematic because of the issues mixing live with pre-produced
content (such as a library of news or sports content, or commercial insertions
where the commercials were produced in standard dynamic range [SDR] or in a
different HDR format).
“The carriage of HDR metadata through the live plant has
some complications as well (although if the hybrid log-gamma [HLG] format is
used, there is no metadata generated),” notes Goldman. “The industry can
certainly define some universal profiles to simplify matters, but that has not
occurred yet. This is partially due to the newness of this technology, but it’s
also partially a result of disagreements over which methodology is the best one
to use.
Using dynamic metadata – or dynamic display mapping - is
also much more challenging to implement in live production. It is therefore unlikely
to be implemented in the near term, except as a pass-through of some premium
pre-produced content.
“4K HFR is extremely unlikely to be used due to its
increased complexity and added baseband bandwidth requirements,” says Goldman.
“As more and more UHD services are launched, then more understanding will
occur, which will hopefully lead the industry to ‘best practices’ and
recommendations.”
The UHD-1 Phase 2 specification also includes Next
Generation Audio (NGA), a technology providing some compelling reasons to
implement. For example, personalisation of audio objects (such as adjusting the
volume of the dialogue track to hear it better), relocatable objects (moving
the location of the source of a particular sound), and a life-like 3D surround
sound field.
“The availability of consumer ‘sound bars’ also makes it
much easier for consumers to realise an impressive 3D sound field without the
need for (or the resulting difficultly of installing) a large number of
speakers in the room,” notes Goldman. “As such, some deployments will implement
NGA, with or following HDR.”
High Frame Rates are a tougher issue because bandwidth and
processing power doubles from 60Hz to 120Hz means that the infrastructure needs
to be replaced, or codecs need to perform better to keep the bandwidth within
current limitations.
“The processing capability is there, and the ability to
carry streams even uncompressed is available for facilities to use (100GbE for
instance) it’s a matter of balancing the cost of investment with the money you
can make from it,” says Green. “HFR seems to be much lower down the list than
4K or HDR at the moment because the visual impact on its own isn’t compelling
enough to make viewers pay more for the content, even though new TVs could
probably quite easily support faster frame rates.”
OTT operators have the advantage of being able to test new
formats over a ‘dumb’ broadband pipe, with the only changes required to process
the signal being in the client device (and software downloadable in many
cases). So, there already are some services up and running using up to
2160p50/60 (4K) with basic HDR (HLG10, PQ10, or HDR10).
Almost surprisingly is the OTT industry which is leading the
UHD service delivery, although the strain it puts on the delivery system, both
at the CDN and end-device level, means services are only available to few.
Service providers such as Amazon, Netflix, Facebook and YouTube have embraced
and promised to offer UHD to their users in an effort to both serve and further
generate consumer demand. This is now driving improvements along the whole
media delivery chain, including the codec of choice for UHD. The discussion on
next generation codec formats, including HEVC, AV1 and PERSEUS, has never been
so intense.
“True bandwidth availability is a key factor that will
influence the widespread development and adoption of UHD services, especially
for connected devices, whether to a mobile or fixed network,” argues Fabio
Murra, SVP Product & Marketing, V-Nova. “The problem is that today’s
networks still struggle to deliver data at the low latency and high bandwidth
required to reliably stream UHD content. This is primarily due both to the
large size of UHD video streams and the overall increased demands placed on networks
following the rapid rise of IP-based video consumption. While telcos continue
with costly and lengthy investments in upgrading and improving their mobile and
fixed infrastructure, compression can help service providers improve the
quality of their services and launch new ones, like UHD, today.”
The issue of severely disparate regional broadband speeds
affects developed countries as much as developing ones. Murra cites Akamai’s
State of the Internet report 2017 into the US which indicated that fixed broadband
video connections ranges from 12 to 28 Mbps on average. “This often diverges
greatly from real bandwidth availability, especially when analysed at peak
times,” he says.
A recent McKinsey report consolidating data analytics from
large video operators found that 32% of video sessions in fixed broadband
households had connections of less than 1 Mbps, with only 10% of video
delivered at more than 3 Mbps. With UHD content requirements being placed
around an average of 25 Mbps, Murra insists more focus must be placed on how
the industry addresses the challenge of real broadband capacity for very high
quality content.
“In mobility the experience is even worse, with hardly any
service offering resolutions higher than 720p today,” he says. “With 4G
networks still falling back onto 3G and EDGE on many occasions and 5G years
away from widespread use, it is only recent innovations in video codecs and
compression technology that can help providers deliver monetizable high-quality
services. We already demonstrated that UHD video can be delivered at 6-8 Mbps,
making it a valuable proposition for the mass-market.”
