Streaming Media

 
Streaming Media on Facebook Streaming Media on Twitter Streaming Media on LinkedIn Streaming Media on Google+ Streaming Media on YouTube
Sponsors

Apple TV Goes 4K
Company finally catches up with Roku, hints that the new video encoder for iPhone 8 and iPhone X is HEVC

At an event today at Apple's new Steve Jobs Theater, the company's CEO, Tim Cook, announced the new Apple TV 4K.

"There's an even bigger advancement than 4K, and it's called high-dynamic range," said Eddy Cue, Apple's senior vice president of internet software and services, while detailing the fact that the Apple TV 4K has a redesigned user interface to take advantage of the significantly higher number of pixels.

The new Apple TV has the A10X chip, also used in the Apple iPad Pro, which more than quadruples the graphics delivery on the new Apple TV 4K.

Cue also announced a partnership with major studios that will benefit those customers who bought an HD version of a movie from the iTunes Store: Those movies will be automatically updated to 4K HDR versions for viewing on the Apple TV 4K.

Cue also mentioned the fact that Apple is driving towards the goal of offering live sports on the Apple TV, alongside on-demand 4K content from Apple, Netflix, and (in a few months) Amazon Prime.

Cue used the example of a basketball game to illustrate ways that Apple TV can prompt users to watch their favorite team's game that's about to start, or even prompt the user to "tune in" to a game that's particularly close.

Finally, Cue mentioned that Apple TV 4K will be able to AirPlay 4K photos, or even standard photos, which typically are shot in a bit-depth expanded to a color gamut equal to or better than HDR.

The company was short on other technical details, but several industry experts have already delved into betas of the Apple operating systems—including the Apple TV's tvOS, as well as the iPad and iPhone iOS 11—and come up with some surprising details around minimum bandwidth requirements for 4K.

To best understand the changes required to stream 4K to an Apple TV 4K, consider the minimum requirements to watch today's Apple event on a pre-4K device. Live streaming of the event uses Apple's HTTP Live Streaming (HLS) technology.

"HLS requires an iPhone, iPad, or iPod touch with Safari on iOS 9.0 or later," Apple noted on its special events page, "a Mac with Safari on macOS v10.11 or later, or a PC with Microsoft Edge on Windows 10."

"Streaming via Apple TV requires an Apple TV (2nd or 3rd generation) with software 6.2 or later or an Apple TV (4th generation)," Apple noted.

What about the minimum requirements for 4K (Ultra HD, or UHD) content?

According to a Tweet by Steven Troughton-Smith, an app developer who dove deep into the codebase of Apple's iOS 11, there will be a minimum requirement for 4K on the Apple TV.

Troughton-Smith found a code line labeled "NetworkNo4KForYou" and noted in a Tweet earlier this week: "Apple's 4K streaming on the upcoming 4K Apple TV requires a 15Mbps connection."

Troughton-Smith also noted that native 2160p, which is 2 times the vertical height of 1080p, will also support a number of color and bit-depth resolutions. Some of these will include 10-bit video, known to consumers by the moniker of high-dynamic range (HDR).

These HDR standards include HDR10 and DolbyVision, but Troughton-Smith also highlighted the fact that 4K can be delivered in standard dynamic range (SDR) as well.

The iPhone X, part of Cook’s “one more thing” teaser in an homage to the late Steve Jobs, will also be the first iPhone to offer HDR with both HDR10 and DolbyVision.

What's interesting about Apple's choice to require a 15Mbps minimum bandwidth connection for Apple TV to be able to deliver 4K is that Apple has yet to define whether the minimum bandwidth requirement will be for standard or high-dynamic range.

Since both SDR and HDR will be available in a range of color subsampling depths—the low-end 4:2:0, mid-range 4:2:2, and high-end 4:4:4  (see code here) —it is quite possible that a 4:4:4 subsampled 4K video could require a significantly higher data rate than the 15Mbps that Apple TV 4K requires to deliver even a minimum 4K viewing experience.

Which leads to an interesting question. Will all this 4K be in HEVC (H.265)?

Apple did not provide technical details as part of today's event, but Apple's Phil Schiller, the company's senior vice president of worldwide marketing, gave a bit of a hint.

Schiller announced, as part of the new iPhone 8 and the new iOS 11, that the company has built its own video encoder for use with the iPhone 8/s new camera—one that appears to support HEVC.

Schiller highlighted the fact that the new Apple encoder breaks the image down in to "tiles" during the acquisition and encoding time, to analyze up to 2 million tiles per second. HEVC allows for smaller or larger pixel block (or tile) sizes than does AVC. Since this occurs in real time as a part of image frame analysis, Schiller claims this will optimize video shot on the new iPhone 8 or iPhone X, at either 4K at 60 frames per second (fps) or up to 240 fps at 1080p, perfect for slow-motion capture.

The Apple TV 4K will ship on September 22, 2017. The iPhone 8, available in 64 GB to 256 GB sizes, will also be released on September 22, with upgrades to iOS 11 available on September 19.

Related Articles
In a software-heavy WWDC keynote, Apple announced several improvements to the Apple TV tvOS, but hardware with 4K video support was nowhere to be seen.
According to unnamed industry sources, Apple is working with publishers and broadcasters to create a universal online TV directory.
Trying to remember where a streaming show is located can be a pain. Apple takes the sting out of video apps by creating one app to rule them all.
There may be peace in our time between Amazon and Apple. While that's good news for home streamers, it suggests Apple is no longer interested in creating a skinny bundle.
While Apple hasn't updated its TV streaming device in two years, an update could be only weeks away. Is 4K finally coming to the Apple TV?