The development of standards for ultra high definition television (UHDTV) offers tremendous promise for enrichment of the in-home viewing experience. Adoption of such standards, and the subsequent rollout of UHDTV services, is becoming increasingly attractive with the ongoing evolution of imaging, processing, and transport technologies, as well as the near completion of the HD migration in many areas.
Manufacturers of display systems rightly see ‘beyond HD’ standards and services as drivers for consumer adoption of premium next-generation products. At the same time, pay TV operators and even streaming video service providers understand the standards’ potential to support their launch and delivery of premium programming and channels.
How exactly can UHDTV standards move the industry forward and facilitate provision of better-quality content? The standard for true UHDTV that is defined in ITU Recommendation BT.2020 and SMPTE ST 2036-1 incorporates parameters for higher resolutions, with UHD-1 specifying 4K and UHD-2 specifying 8K, and also for higher frame rates (HFR) and bit depths, with a wider colour gamut.
UHDTV standards dictate frame rates of up to 120 frames per second (fps), compared with the current standard of 50 or 60 fps that ultimately could yield much smoother movement and better detail during camera pans. With this increase in frame rate, which is perceptible at up to six times the picture height, the UHD-1 and UHD-2 standards stand to add significant visual value for the consumer.
By defining a much higher bit depth (the number of bits used for each color component of a single pixel) of 10 or even 12 bits rather than the 8 bits specified in the HDTV standard, UHD-1 and UHD-2 pave the way for two key gains: much better colour precision and the ability to express a broader range of colours. At the same time, the higher dynamic range (HDR) indicated by UHDTV standards ultimately has the effect of making the differences between light and dark areas of an image much more perceptible for the viewer. Together, these enhancements hold out the possibility for more realistic colours and better visibility of elements within the image.
There is no question that UHDTV’s combination of higher resolution, HFR, higher dynamic range, and wider colour gamut promises significant improvements to the quality and impact of moving images. Other cited benefits include a stronger sense of ‘realness’, in addition to the larger field of view that brings the cinema experience to the home, and these gains are complemented by enhanced audio specifications and technology. For many broadcasters and other content providers, however, a number a critical questions persist. Among these is whether to embrace UHD-1, which would indicate a commitment to 4K resolution, or to wait and go with UHD-2, which would require the leap to 8K.
A broader palette
This is a nontrivial matter, given that the move from HD to 4K alone requires significantly more data. With the shift to 8K resolution, demanding many times that yet increase in pixel resolution, as opposed to the other factors examined here, offer the least perceivable impact for viewers positioned more than a couple of yards from the screen.
That said, the growing volume of content acquired at higher resolution and in higher-quality formats is providing value to broadcasters long before delivery. In practical terms, they offer a broader palette with which to work, and this is particularly valuable for premium programming such as live events, which often are characterised by unpredictable lighting and speed of movement within the frame.
Considering future plans for UHDTV from the business side, UHD content creators and distributors will likely need to address factors such as an initial scarcity of content, the higher costs involved in creating and delivering content, the limited number of consumer displays equipped to receive and display UHD video, and the impact of UHDTV on the services they currently provide.
Questions on the technical side include standardisation — or at least minimisation — of different profiles used to set parameters for frame rate, resolution, and bit depth, as well as how best to optimise the end-to-end chain (whether streaming, satellite, or OTA) for a UHD format and maximise efficiency. The technical and practical aspects of delivering UHD content to home viewers requires the attention of standards bodies worldwide, and also of platform and network operators, the professional production industry, and consumers.
Produced in association with the Society of Motion Picture and Television Engineers (SMPTE), the ‘Go With UHD-1 or Wait for UHD-2?’ session on Sunday 14 September 2014, at 16:00, IBC2014 brings together major players in the international broadcast industry to discuss UHDTV challenges and opportunities and to outline their strategies for moving toward UHDTV.
Speakers will consider the adoption of UHDTV technology from the points of view of content creation, asset management, and delivery to the consumer. Their presentations will be followed by an informative discussion in which they will review professional industry and consumer roadmaps for the two phases of UHDTV and the requirements for standards. The large investment in product development for UHDTV and its speed of acceptance in some areas promise to make this session both controversial and educational.
The fact of the matter is that true UHD is a long-term goal. Many broadcasters have small budgets, and those limited resources are currently focused on finalising the HD shift and on establishing trimedia operations — taking an integrated approach to radio, broadcast, online, and streaming media. Though the move toward UHDTV will take an extended effort, activity across the industry is looking very promising.