In the past few years, 4K video has rapidly moved from concept to everyday consumer electronics. It's now common to find 4K screens on televisions, computer displays, and smartphones. Consumers get their 4K content from new cameras and even Netflix. But, does 4K have a place in your video-ready conference room?
4K and higher resolution solutions are now being touted by video conferencing vendors and providers such as Cisco, Logitech, and Vidyo. Whether there is a need for 4K video conferencing technology is presently creating interest and confusion, but to me the answer is easy -- yes.
A Clearer Picture
First, a little comparative history. Most of us grew up with what's now called standard-definition (SD) analog television. Not long ago the world discovered the benefits of high-definition (HD) digital video. This was at about the same time as new, flat-screen televisions made their debut, and when broadcast stations switched to digital, so there was plenty of incentive for consumers to upgrade their equipment.
The shift from analog to digital meant we moved from counting lines to counting pixels. How many pixels? That's complicated to answer because there's different types of HD. In simple terms, 720 HD is 1280 pixels wide by 720 pixels tall -- that's about twice the detail of SD. 1080 HD is 1920 pixels wide by 1080 pixels tall -- that's about five times the resolution of SD.
While SD lasted for several decades, HD barely made it ten years until even higher-than-HD resolutions arrived. As the case with HD, there's different types of 4K video. It's easy to think of 4K as four times greater than 1K (1080), but it's not like that. 4K video has about 4000 pixels of horizontal resolution. No, that's not a typo - the 1080 in HD referred to vertical pixels, while 4K refers to horizontal pixels.
As mentioned there are multiple types of 4K video. They differ primarily in horizontal lines or aspect ratios. Since they all tend to use around 4K pixels for horizontal, it's easier to refer to this whole class or generation simply as "4K video."
4K in Use
Don't feel bad if you don't have 4K -- it's still new and there's not that much content available yet. YouTube started supporting 4K in 2010, and 4K first appeared in movie theaters in 2011. Reasonably priced 4K televisions and computer displays began showing up on the market about two years ago.
Currently, most video conferencing is done in 720 and 1080 HD formats. A nice thing about modern video conferencing solutions is they adjust quality up or down on a per-site basis, as opposed to a per-conference basis. This means that in a given video conference, two sites can enjoy the highest possible resolution, while a third user sitting in a Starbucks will get by at a lower resolution.
At Enterprise Connect about a month ago, Cisco launched its Room Kit solutions, which tout a 5K camera. Many people wonder, is this a feature or simply marketing hype? To answer this question, it's necessary to move away from discussing the general purpose 4K video, and look more deeply at three separate video conferencing functions: video capture and encoding, transmission, and presentation.
The 5K sensor in Cisco's Room Kits enables the camera to record very high resolution video. This image can now be digitally processed before transmission (in HD). Digital processing, such as digital zoom, results in a loss of resolution. So, if you start at a 5K resolution, there's plenty of room for loss without compromising HD (1080) quality. In this case, Cisco is using a 5K sensor for video capture and encoding, but not for transmission.
Logitech recently launched its BRIO 4K USB webcam. The webcam supports (compressed) 4K video. However, that's unrelated to what your video conferencing software supports.
In addition to video-conferencing, a webcam can be used for a variety of other applications. For example, BRIO could be used to create a 4K training video. With regards to conferencing, the BRIO, like the 5K camera in the Cisco Room Kit, enables advanced digital processing such as its 5X digital zoom while maintaining quality for a 1080 image.
There are not many enterprise video conferencing solutions that offer 4K transmission (yet). However, Vidyo offers 4K transmission with its recently introduced Vidyo.io API service. So, 4K video is available today for use cases that require it.
There are situations where that digital zoom feature needs to be controlled at the remote end of the conversation – often in surveillance, security, and medical applications. For example, a hospital could use 4K video to monitor high-risk patients.
Transmitting 4K video requires a data connection of about 15-20 Mbps. But keep in mind, that's only to the 4K sites. Vidyo.io will send lower HD quality over connections that traverse links with insufficient bandwidth or the public Internet.
The final part of the equation is presentation. Most video conference rooms use a separate display for shared content. It's pretty easy to see the need for 4K support in this area, as laptops that serve/share this information increasingly have 4K video display capabilities.
Video conferencing isn't just about resolution, but motion too. Detailed spreadsheets don't move much, so it's reasonable to transmit 4K video resolution over an HD capable network by sending slower refreshes. This is particularly useful with the detailed images found in architecture and medical applications. It requires coordination between the video service and the endpoints -- Cisco and Vidyo both offer this feature.
So, to reiterate, the answer is yes, 4K is a real thing in video conferencing. Enterprise customers should consider 4K+ cameras, 4K+ displays, and evaluate 4K transmission services if it's justified by the use case.
Dave Michels is a Contributing Editor and Analyst at TalkingPointz.