A picture might be worth a thousand words, but a high definition display is worth over 8 million pixels in every single frame. Digital Cinema 4K has been in existence since 2003, but recent exposure at headlining events like CES and InfoComm 2015 continues to stir up interest in the display technology. To help bring you up to speed, here’s a 4K Video 101 crash course.
What Is 4K Video?
The answer is, it depends on who you ask. If you are an LED display or TV manufacturer, you will refer to 4K video as 4KUHD video, which is basically a marketing term coined to describe a resolution and refresh rate for displays of 3840 X 2160 @ 30Hz. The moniker “4K” comes from rounding off the number of pixels in the width of the image, a departure from the previous usage of the height of the image in the 1080p HD generation. 4KUHD video is currently what the average person is actually referring to when describing 4k video.
Coincidentally, 4KUHD resolution reflects the hardware limitation of manufactured LCD displays to date. However, before the term 4KUHD video came into prominence, digital cinema described 4K video as 4 X 1080P video, which equates to a resolution and refresh rate of 4096 X 2160 @ 60 Hz. This is now known as “true 4K”. With a resolution of 4096×2160 pixels as established by Digital Cinema Initiatives (DCI), 4K video is the next major step in high definition displays.
Projectors capable of true 4K resolutions have been available for years in digital cinema, but in the AV world 4K video content has been lagging, with most applications resorting to “upscaling a 1080p input image to four times the resolution for screen projection, which is not ideal when compared to “native” 4K content.
Today, both graphics card manufacturers and display manufacturers are driving the “4K revolution.” To enjoy the benefits of 4K video, you need a 4K source and a display to view it on. Graphic cards can currently output 4KUHD resolution or “true 4K” resolutions while utilizing a reduced color space in order to lower bandwidth for transmission, a current technical hurdle. In the near future, upgraded chip sets from manufacturers will enable graphics cards to be produced that drive true 4K resolution with full color space information, allowing for greater perceived image quality.
For Your Viewing Pleasure
The increased pixel density and smaller pixel size of 4k video performs better at tricking your eyes into turning the screen into a single image rather than a collection of individual pixels. The effective result is that you can use larger displays at closer distances than ever before, for a truly “immersive” viewing environment. The difference in image quality experienced when upgrading from standard to HD televisions is as pronounced as “night and day,” while the enhanced picture fidelity and crispness of moving from HD to 4K is less dramatic, more of an incremental advance, but nevertheless desirable. Future 4K advancements will most likely come in the form of color fidelity (for a more realistic and lifelike image) and increased frame rates (which will provide improvements in moving video fidelity and accuracy).
The “Downside” of 4K Video
When you increase the number of pixels in each frame, the information required to create the display scales linearly alongside the rising density. 4K video has 8,847,360 pixels needing data on what colors and brightness levels to use, compared to the 2,332,800 pixels per image—a 400% difference—in a standard 1080p video. This exacerbates the same problem that HD had in its early years: distribution.
With the widespread availability of broadband Internet connections and the market saturation of HD-capable screens, HD video is now widely available on YouTube, Netflix, Amazon, and other major streaming services. This wasn’t the case earlier in its lifespan, when download times went well into hours and days rather than being able to buffer as you watch the video.
At four times the size of the same video in an HD format, a 4K video can weigh in at 100 GB or more. Even with a healthy download speed of 10 Mbps, it will take a 4k video over ten hours to fully download. Because of this, 4K breakthroughs are occurring first in high-end commercial, government, military, medical and live entertainment venues and digital cinema industries, and will eventually make their way down to residential homes as improvements in networking technology standards occur and prices drop on 4K televisions. Morever, the commercial world is moving to a 10GE Ethernet network infrastructure in order to better accommodate moving 4K video around, and fiber optics has been available for some time as an alternative video distribution system.
The Future of 4K Distribution
Much like the adoption of Blu-ray and HD, the prevalence of 4K video starts in the commercial industries. When it becomes the norm for the average consumer depends on the interaction between consumers with 4K-capable sets and producers creating content for dissemination. Cable TV providers are now starting to disseminate in 4K, but this content is still only available to high-end residential customers and early adopters.
That said, filmographers and the new Ultra HD Blu-ray standard are already producing their master copies in the higher resolutions in an effort to prepare for 4K’s surge from the buzzing hype it currently enjoys to its inevitable role as a true market player. Whether you adopt 4K now or later, you can safely expect it to supplant HD television within a few years.
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