Reining in the Bits and Bytes

Virtual-reality apps and the growing mix of 360-degree video experiences are designed as immersive experiences that wrap a digital world around the viewer. And while apps and offerings alter the landscape that users see as they look up, down and all around them, this sphere of digital imagery can also represent a big bandwidth challenge if that content is being streamed at a high enough bit rate so as not to appear as a pixelated mess.

While the bandwidth requirements for 4K video gets knocked because the format packs in four times the pixels of an HD image, it’s got nothing on VR.

In an interview earlier this year, CableLabs CEO Phil McKinney estimated that a good VR experience requires at least 120 frames per second and a resolution of at least 4K in the user’s “viewing space.” If that kind of resolution and performance is to be applied to a 360-degree environment — not just a flat, two-dimensional rectangle — that could push streaming requirements into the lofty heights of 150 Megabits per second to 250 Mbps.

That isn’t very bandwidth-efficient and it’s downright wasteful, because it implies that the same bit rate and resolution would be used in portions of the 360-degree sphere that isn’t being viewed at a given moment.

A company that’s helping to address and fix this is a startup called Visbit, a VR and 360-degree video-streaming company that is coming off a $3.2 million seed round from several investors, including Presence Capital, ZhenFund, Colopl Next, Amino Capital and Eversunny Ltd.

It’s tackling it with a technology it calls View-Optimized Streaming (VVOS). Rather than using a uniform bit rate and resolution for the full 360-degree view, VVOS automatically ratchets up the bandwidth of the images appearing in user’s current field of view, the company said.

VR and 360 video simply “needs more pixels than regular video,” Dr. Changyin Zhou, Visbit’s cofounder and CEO, said, noting that it presents a “big gap” between network and content requirements.

In Visbit’s view, 4K is the lowest quality acceptable for 360-degree videos, holding that the best quality will require 6K, 8K, or even 12K resolution.

Visbit’s current platform supports up to 8K resolution, but is predicting that by about 2020 consumers will be watching video in 12K or 16K. Last year, Samsung announced it was working on an 11K mobile device, with VR its most obvious use case.

Zhou, who started up Visbit after serving as a software engineer and scientist at Google X, estimates that the company’s VVOS technology, which handles the transcoding and streaming of the content in the cloud, can cut bandwidth requirements by 50% to 80%. To complete the technology chain, Visbit has also developed a software development kit (SDK) that its partners can weave into their VR applications.

That combo, he said, will ensure that the content can be delivered wirelessly to VR headsets using WiFi and LTE technologies without too many worries about buffering and other streaming-related ailments.

Visbit’s platform is currently in closed beta trials ahead of a commercial rollout slated for some time in 2017. But is already working with several VR content companies, including Primacy, Variable Labs, Cloudwave, Fluidcast and Realiteer, a maker of VR psychotherapy apps.

Visbit’s initially focused on platforms such as the Oculus-powered Samsung Gear VR and Google Cardboard, but expects to support more mobile and tethered VR platforms in the coming months.

“We are device-agnostic,” Elaine Lu, Visbit co-founder and chief operating officer, said.

However, she said she also expects Visbit to focus more heavily on mobile VR systems because consumers tend to use them more often to watch 360-degree video.

That appears to be the case with the Samsung Gear VR, which must be paired with a smartphone. In an interview earlier this year, Nick DiCarlo, vice president of immersive products and virtual reality at Samsung Electronics America, said that video usage on the platform early on had surprised the company, and that only about 40% of the apps for Gear VR are for games.

Founded in 2015, Visbit is based in Sunnyvale, Calif.