The specs for Ultra HD  Blu-ray  have been revealed; here's what to expect from the next generation of optical discs and players.

One of the most eagerly anticipated developments in the world of 4K/UHD is a next-generation optical-disc format that will deliver the best-quality video and audio to consumers. At CES 2015, I learned that the specification for this format is nearly complete, and I'm happy to report the confirmed details here.

First, the official name of the new disc format is Ultra HD Blu-ray—not Ultra  HD Blu-ray Disc  and not UHDBD, UHD BD, or UHD-BD (though I'm sure many will use one or another of these abbreviations). Licensing is expected to begin mid-year, which means the spec will be completely finalized by then.

Speaking of the spec, it's pretty much done, defining what a player and disc must support as mandatory and optional. The goal is to make the format as future-proof as possible so that new capabilities can be accommodated as they are developed.

Discs will be available in two varieties—66 GB dual layer and 100 GB triple layer with data-transfer rates up to 108 Mbps from a 66 GB disc and up to 128 Mbps from a  100 GB disc . The laser system is roughly the same as the current  Blu-ray  spec tuned for the new higher-density disc structure. Obviously, the pixel resolution will be up to 3840x2160, and players will have  HDMI 2.0  outputs with HDCP 2.2 copy protection. Finally, HEVC encoding will be used.

Ultra HD Blu-ray players must be able to read both of the new formats as well as HD Blu-ray discs. Other mandatory features include support for high dynamic range in the form of SMPTE ST 2084 and 2086, which are open standards that include PQ gamma. The HDR info is encoded as metadata so the content can be played on a non-HDR display. Also, players must support frame rates up to 60 fps and color gamuts up to BT.2020 with 10-bit resolution. Finally, they must decode all the current audio formats and provide passthrough for all immersive-audio bitstreams.

Optional features that manufacturers can choose to implement or not include support for Dolby Vision and Philips HDR as well as DVD and CD playback. Another optional feature is called Digital Bridge, which will let the player copy Ultra HD  Blu-ray  content from the disc to internal storage if available. It also allows you to export an HD or SD copy of the content to an external device for portability. (The rep I spoke with didn't know if Digital Bridge would let you export full-resolution UHD content.)

The discs themselves support all these features, but none are required—studios can choose what they want to put on the discs. It's a blank canvas, and content creators can include what best serves their artistic intent. For example, some discs might include high frame-rate content, but others might not based on the director's preference.

The official logo has not been finalized yet—the graphic at the top of this post is just something I threw together—and there are a few other minor details to work out, but I'm delighted to know what to expect from the next-generation optical-disc format. With licensing scheduled to begin mid-year, I suspect there might be actual product in the market by CES 2016.