Two new connectivity standards recently launched point to an 8K HDR future. Are you ready? Paul Milligan finds out all you need to know.
There are tech updates in the AV market that feel seismic at the time and will go on to have a significant impact on the industry for years afterwards. And then there are others that have a far more subtle effect on how integrators go about their daily work. The issue of connectivity, especially when a new format is introduced into the market, can often go unnoticed with little initial fanfare, but the long-term impact can be wide-ranging and write its own page in AV history.
When changes in connectivity become widespread, when the move from VGA to DisplayPort took place for example, it affected millions of AV devices.
New products simply have to feature the new connectivity, otherwise they run the risk of not being futureproof in a way that could prevent sales, and old products (or more likely the integrators that look after them) have to find a way to accommodate the changes.
This article will look at two brand new forms of connectivity we think could have a big impact on the AV world, in the form of HDMI 2.2 and GPMI. It may seem strange to talk about HDMI as new, considering its first iteration (1.0) was launched back in 2003.
With the rise of HD technology in the early 00s, HDMI came along to largely replace older analogue video standards such as composite video, S-Video, and VGA, and was backed by the biggest big names in electronics at the time – Sony, Panasonic, Hitachi, Toshiba, and Phillips (amongst others). Its success has been impressive, by 2013 more than 3 billion HDMI devices had been sold, by 2021 this number was up to 10 billion. HDMI 2.0 was released in 2013 to meet the demands of UHD technology.
First announced at CES in January this year, HDMI 2.2, was released in June. Why should we care about an update? Well, this one was significant. HDMI 2.2 doubles the potential bandwidth of current HDMI 2.1, taking it from 48Gbps to 96Gbps. This also goes beyond the bandwidth of DisplayPort 2.1 which can support up to 80Gbps. What is interesting is that even though the early headlines around HDMI 2.2 were dominated by the biggest number (96), it can support 3 bandwidths; 64 Gbps, 80 Gbps and a top speed of 96 Gbps.
HDMI 2.2 provides options for uncompressed and compressed video and chroma sampling, and compression and chroma subsampling can enable higher resolutions and refresh rates including 4K@480, 5K@240, 8K@240, 10K@120 and 12k@120.
It can also handle uncompressed full chroma formats such as 8K60/4:4:4 and 4K240/4:4:4 at 10-bit and 12-bit colour. Doubling the bandwidth from 2.1 to 2.2 is not just a quest for greater and greater numbers says Brad Bramy, vice president, marketing and operation, HDMI Licensing Administrator (HDMI LA). It’s about what you can do. “It’s not so much that people need this gigantic bandwidth. It gives people a lot more options for how content is going to be created or how it’s going to be distributed, processed, and how it’s going to be consumed when it reaches a consumer or commercial user. It allows for higher frame rates, which is really noticeable when you go from 30fps to 60fps for much smoother pictures.”
It also supports next-gen HDMI Fixed Rate Link technology, so that when you use a HDMI 2.2 certified (and compatible HDMI cable) device, your display will show a native video format without any errors.
The benefits are not just for consumers, but for the proAV space too. Bramy adds: “The higher bandwidth is going to be really needed for some commercial spaces, whether it’s for esports arenas or digital signage or mega signage installations at stadiums. It will be useful for VR, where people have goggles and have two individual displays that need to deliver a signal to both of them, the higher bandwidth lets each one get higher resolutions and much better frame rate.” Because of the extra clarity and higher resolutions, HDMI 2.2 could provide real benefits for the medical imaging sector too.
Is part of the push for HDMI 2.2 to get everyone 8K ready? “People say there’s no [8K] content. We demonstrate 8K all the time, and I talk to TV manufacturers all the time. The upscaling is amazing, and there’s a real difference [between 4K and 8K], but it’s a choice and people aren’t clamouring to get it. Right now, it’s about delivering a better 4K experience. Because I’d rather have 4K 10-bit colour than 4K 8-bit colour.”
How will it work in principle? Well, HDMI 2.2 will require a new cable, officially called an Ultra96 cable. Ultra96 is the name manufacturers are being encouraged to use to indicate a product supports a maximum of 64Gbps, 80Gbps or 96Gbps bandwidth. The physical connector is the same, and these cables will be backwards compatible with previous HDMI versions. Users will need an Ultra96 cable to support the new spec and speeds if connected between end-to-end HDMI 2.2-compatible devices.
The new Ultra96 cables (pictured below) will be a part of the HDMI Cable Certification Program which requires each length of a cable offered by a company to be tested in order to carry the certification badge. Not only will that test look for bandwidth compatibility, but it will also be tested and certified to ensure low EMI, to reduce the possibility of interference with wireless networks, streaming media players, Bluetooth devices and mobile phones. How long will Ultra96 cables run for? Well, we don’t know that yet.
The HDMI-forum website states: “The specification does not indicate a cable length. Cable length depends on many factors including cable type and construction.” With that amount of data to carry it’s not unrealistic to think the cables will be two- or maybe three metres in length maximum.
GPMI (General Purpose Media Interface) was launched in April this year when chipmaker HiSilicon published the standard in a whitepaper on its website. It has been created by the Shenzhen 8K UHD Video Industry Cooperation Alliance, a consortium of more than 50 (all) Chinese technology companies including Huawei, Hisense, HiSilicon and TCL. Other big Chinese brands such as Huawei and Xiaomi, while not part of the Alliance, have said they will support GPMI as a standard.
It has already obtained official approval from the USB Association, according to Hong Kong’s HKEPC, which should remove any potential compatibility issues with hardware already in use. “GPMI is an innovative achievement and a core technological breakthrough in the audio and video industry,” said HiSilicon, when setting out the goals behind the launch. “It integrates the functions of video transmission, data interaction, network connection and power supply, and realises that one interface can support the full business needs of ‘audio and video + data + network + control + power supply’.”
GPMI is designed to transmit UHD video, high-fidelity audio, data, control signals, and power through a single cable. Why should we care? Well, it can reportedly support up to 192 Gbps of video and audio (through a Type-B connector), twice that of HDMI 2.2, and four times that of HDMI 2.1 and DisplayPort 2.1. GPMI Type-C version will use the existing USB-C connection, which is the same as Thunderbolt 5 (used on Apple Macs and some high-end Windows PCs). Both Type-C and Type-B will be capable of supporting 8K UHD video transmission. In terms of power, GPMI can deliver 240 watts of power through a Type-C connector, enough to run a laptop, or up to 480 watts of power through a Type-B connector, which can cope with a large 8K display, or a powerful esports gaming setup.
In an article entitled ‘GPMI Explained: The Future of AV Connectivity?’ by John Berkovich published on the AVIXA website, he puts GPMI in context with HDMI and USB-C. “Unlike HDMI, which is primarily focused on video and audio transmission, GPMI expands its scope to include data networking, device control, and power delivery. While HDMI 2.1 supports 8K video and eARC for high-quality audio, it lacks native networking and significant power capabilities. GPMI, on the other hand, is designed to be a complete AV-over-IP-ready solution.
Compared to USB-C, which does offer power, data, and video in one connector (primarily through Thunderbolt 4 or DisplayPort Alt Mode), GPMI differentiates itself by being purpose-built for high-bandwidth AV systems and larger-scale commercial deployments. USB-C is more consumer-oriented and constrained by cable length, whereas GPMI targets enterprise-grade infrastructure with greater power delivery and longer cable runs. In essence, GPMI combines the strengths of HDMI, USB-C, and PoE (Power over Ethernet) into a single, scalableinterface - potentially redefining how AV systems are connected and controlled.”
In addition, GPMI also features the ability to control equipment similar to the way HDMI CEC can do, so one GPMI-enabled device, such as a TV, would be able to power a connected device such as a console or amplifier, eliminating the need for multiple cables.
Berkovich’s article looked at the potential applications of GPMI in pro-AV projects, and found there to be many. For example, “In large-scale display environments such as videowalls, control rooms, and public-facing digital signage, GPMI’s unified cable architecture eliminates the need for separate power lines, control interfaces, and signal extenders. By delivering high-resolution video, network control, and substantial power through a single cable, GPMI enables cleaner, faster installations with fewer points of failure.
Its daisy-chaining capability is especially advantageous in tiled LCD or LED videowalls, where multiple displays can be linked directly without the need for external switchers or repeaters. This not only reduces hardware costs
but also enhances reliability and scalability for integrators managing multi-display systems.”
Conference rooms, meeting rooms and collaborative spaces will benefit because GPMI can meet the demands for minimal cabling and BYOD workflows as it can handle high-bandwidth video and deliver power and control peripherals, cameras, microphones, and touch displays. “GPMI’s ability to support real-time collaboration tools and interactive systems makes it especially well-suited for hybrid meetings, where participants need smooth, low-latency video and device interoperability across physical and remote spaces,” says Berkovich.
Industrial applications can also benefit from GPMI says Berkovich because cable reliability is so vital in factory automation, robotics, and mission-critical control systems. “One GPMI cable can power sensors, actuators, or embedded controllers (up to 480W), stream high-resolution imaging or real-time video feeds, and transmit bidirectional control signals for programmable logic controllers (PLCs) or SCADA systems. For example, one GPMI cable can simultaneously power a laptop, transmit presentation content to a display, carry back touchscreen data, and maintain a secure network tunnel without the need for adapters or separate cables.”
So far so good, eh? Well yes, but a few areas of concern have also arisen on GPMI. It only features Chinese companies so far, so will it expand beyond the domestic market? Or stay just in Asian markets? Other concerned voices have enquired because this is a solely Chinese initiative so far, is this an attempt by the Chinese government to create IP of its own, so it’s not dependent on other parts of the world? The China 2035 plan, published in 2020, outlined an ambitious plan for the country to write global standards for the next generation of technology, a move that could have enormous implications for technology industries globally. It’s perhaps no surprise that China’s share of patent applications is more than a quarter of all applications filed for example. GPMI could be another piece in this puzzle.
With any evolution in connectivity, there’s always a significant portion of the AV world happy to play ‘wait and see’. And that’s perfectly understandable, it’s a significant upheaval to move from one connectivity standard to another after all, given the sheer number of devices (and time and inconvenience) involved. Even in that ‘wait and see’ period some will move across early, and others will wait till they have to respond, the only guarantee is that moving to a new connectivity standard will be a gradual process.
There are clear benefits to both HDMI 2.2 and GPMI, both point the way towards an 8K HDR future. Will we be talking about both of these technologies in 10 years’ time? No one can really answer that with any certainly, but it’s something the industry has to be aware of, so we can offer the best available technology to clients at all times.
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