4K Blu-ray could be on track for Christmas 2015 release
4K has been a long time coming; Ultra HD video represents the next big jump in image quality since TVs switched from cathode ray tubes to pixels, but the huge file sizes, lack of content and expensive TVs have meant we've been stuck with Full HD. That looks set to change next year, as the Blu-ray Disc Association has finally revealed the first prospective details for a 4K version of the format.
The 4K Blu-ray standard (the name has yet to be finalised) is fast approaching the licensing stage, with all BDA members aiming to have the specification finalised by Spring or Summer next year in order to begin licensing it out to manufacturers. Rather than roll 4K into the existing specification, it will form an entirely new standard, although the BDA is aiming for backwards compatibility with existing Blu-ray discs. This would be similar to how current Blu-ray players are able to play DVD discs, but your old DVD player can't read Blu-ray discs.
Although many of the technical details have yet to be finalised, the BDA plans to support Ultra High Definition 3,840x2,160 resolution video at up to 60fps frame rates. Content will be encoded with the HEVC codec, mastered using the rec2020 colour grading format and 10bit colour depth.
The Blu-ray discs themselves will need to have larger capacities to accommodate UHD video files. Current dual-layer discs can manage 50GB, but 4K discs will aim for 66GB and then 100GB further down the line. That's about as future-proof as it's currently possible to be, which hopefully means there won't be any need for version revisions, software upgrades or new disc formats while 4k is the accepted video standard.
More excitingly, the specification will make allowances for an expanded colour gamut and high dynamic range (HDR) video. Although HDR has yet to be standardized, with companies including Dolby working on its own technologies, many TVs are already capable of massively higher brightness images than the 100nit, rec709 broadcast footage currently being used. By the time the BD4K standard is finalised, we could be seeing significantly brighter, more natural images on future 4K TVs.
The bad news is that you'll need a new player in order to watch 4K Blu-rays. The BDA spokesperson we talked to wouldn't be drawn on whether Sony and Microsoft would be able to update the PS4 or Xbox One , but it's looking increasingly likely that it won't be possible to add in support with software alone.
The association is still deliberating on a name, logo and branding for the upcoming standard, but it should be obvious to customers that the new format will provide much greater detail than existing Blu-ray discs. It has a little over a year to nail down the specifics; if everything stays on track, the BDA hopes that 4K Blu-ray discs and players will be on the market in time for Christmas 2015.
