As streaming becomes a more popular delivery mechanism for live-event video viewing and customers increasingly become used to high picture quality - including 4K - the twain are destined to meet. When they do, the definition of a channel, as viewers know it today, could change, said Eric Grab, CTO of DivX.
Utilizing HEVC compression and MPEG-DASH (Dynamic Adaptive Streaming over HTTP), which aims to standardize adaptive bitrate streaming, DivX recently helped deliver live coverage of a basketball game over the Internet in 4K.
"This is disruptive," Grab said. "It was the highest quality sports event done through the Internet to a device. People asked what cable channel it was playing on, but it wasn't going through a cable channel. The new definition of what is meant by channel and how video is deployed through cable will be a new set of Internet technology."
The basketball game took place in London at the O2 arena. The video was delivered via the Internet and watched in New York City on a big screen TV, hooked up to a PC. The test was limited to a single 4K stream, and the decision was made not to reduce the resolution at any point during the game.
Compared to an HD broadcast, 4K is four times the resolution and has a higher frame rate (50 frames per second) than typical sports coverage. Even with the use of HEVC compression technology, bandwidth requirements are greater for 4K. To replicate the 4K streaming on a larger scale, this additional capacity requirement must be supported down to the last mile. No bottlenecking allowed, Grab said.
In a typical streaming scenario, if someone is watching something in HD, but congestion occurs, the resolution drops to SD. 4K, however, is something being talked about as a premium service. The question becomes, if a consumer is paying for 4K, is going down to HD OK? "Some people might prefer quality over continuous play, but most respond that they don't want interrupted critical moments," Grab said.
Local caching could be a way to help maintain 4K quality, but utilizing caching for a real-time event is difficult. Also, in general, since a 4K broadcast involves more data, if the cache hit works, there is better success; but if it doesn't, there is a larger failure. "The video may stop playing if the cache is not right in 4K," Grab said. "There is two times the data rate in most cases, so there is different tuning happening and different buffering."
Another challenge to 4K streaming on a larger scale is the number of production cameras needed. A typical football game utilizes 30, while an event the caliber of the Super Bowl might have 60 cameras. And of course the chicken-and-egg scenario of getting 4K devices in the home vs. the value of producing 4K content comes into play.
Yet Grab says it is feasible to think that next year's Super Bowl could be streamed in 4K. "The pace at which technology is being updated is quick. It is much faster than when (the industry) was moving from SD to HD."
At consumer electronics stores, "almost everything you find" in the way of TV sets is 4K-capable already, Grab said. "Once a consumer sees 4K, it sells itself. This is not 3D. When you see good 4K at a high-frame rate, (you say) 'I've got to have one of those.' 4K TVs are selling. That is what is in the stores, and that is what people are buying. The quality is good, and (it even) makes HD resolution look a little better."