Deliver Optimized Content to Apple TV

Background

Adoption of ConnectedTVs and OTT devices is expanding exponentially. Recent reports estimate that 17% or roughly 20 million households are using some form of streaming media player, and that number is expected to climb to 39% within 2 years. It's no surprise that Apple TV leads the market in these devices with 39%. Right behind Apple is the Roku with a 28% market share. Because of this, the demand to meet OTT delivery requirements is incredible for content creators and broadcasters in the digital age. We've worked closely with Apple to create presets verified by the Apple engineering team specifically for Apple TV. These presets reflect the latest guidelines published by Apple in September 2014. As you would expect, the presets are for HTTP-Live-Streaming, which Apple brought into the mainstream as the de facto standard for media delivery to iOS. Apple is developing an update to the Apple TV spec currently and we are working closely with them to ensure we are the first to support the format upon release.

Audio/Video Requirements

The requirements for the Apple TV presets are extensive. Ten streams should be created, and you must have at least one 720p stream and one 1080p stream as a requirement. The additional recommended HLS streams appear in the table below.

Apple TV 16:9 Presets (more info here.)

DimensionsBitrateProfileLevelAudio

640x360 800 High 4.0 128Kbps

640x360 1200 High 4.0 128Kbps

950x540 1800 High 4.0 160-256Kbps

1280x720 2500 High 4.0 160-256Kbps

1280x720 4500 High 4.0 160-256Kbps

1920x1080 6500 High 4.1 160-256Kbps

1920x1080 8500 High 4.1 160-256Kbps

Audio Only lo-audio 128Kbps

Audio Only hi-audio 256Kbps

Audio Only ac-3 384Kbps

With the tightening of FCC regulations for closed caption delivery, Apple suggests providing caption tracks using WebVTT, but CEA-608 & CEA-708 are also supported. Forced subtitles are preferred to burnt-in subtitles to make language translation easier. When using WebVTT captions must be defined in the media playlist and broken in in 5-10 minute segments. The Closed Caption attribute should always be specified, and if not in use, should be set to none.

While there are no minimums FPS requirements, you can not go over 30 FPS, and a keyframe should be used every 2-3 seconds.

For Audio, AAC should be used, but AC-3 (AKA Dolby 5.1) can be used a an alternate addition. If using both AAC & AC-3 put the audio in a separate stream for efficiency. Do not use multiple audio bitrates for AC-3. Hi-Fidelity surround sound is important in the OTT context because devices like Apple TV are often part of sophisticated home audio systems that support Dolby 5.1 or 7.1 surround sound.

Other Considerations

Media must be contiguous from segment to segment.

Playlists must use floating-point duration.

Ads must be included in the media playlists, and must use the same codecs and aspect ratios as the primary content.

HTTP redirects are not allowed except in the case of dynamically inserted ads.

Video segments must begin with an IDR frame.

Segment duration must be between 5-12 seconds, but 10 seconds is recommended.

For live streams, at least 5 minutes of content must be in the playlist.

If use AC-3, alternate audio (multi-language), or alternate video (multiple angles), audio and video should have separate playlists.

Streams should always specify the codec & resolution attributes.

Bandwidth attribute should be set to the highest bandwidth for a given segment. The average bandwidth should also be specified.

To enable trick play, you must use an i-frame media playlist. It is also suggested for live content.

I-frame playlist should have a density of 2 i-frames per second.

For testing tools and everything else you need to know, please reference Apple's Streaming knowledge base. In addition to the Apple documentation, you can also reference our API Docs and Apple TV streaming presets.

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