Once again poor old Sony has had more documents leaked, just over quarter of a million this time. While that's bad news for Sony it's revealed some good news for home cinema fans – the company looks like it's working on a next-gen 4K and HDR Blu-ray player.

At the moment Ultra High Definition and High Dynamic Range content does not exist in accessible solid state formats. But according to Sony's leaked document it's planning to create a Blu-ray player that can offer both 4K and HDR playback. This would suggest Sony has known about the discs that store this content for some time.

The Blu-ray Disc Associations has announced that it will be introducing 4K Blu-rays before the end of 2015. These will come in two formats: 66GB dual-layer and 100GB triple player discs. This should be plenty for both 4K and HDR movies.

The question is, will people want to buy another Blu-ray player, on top of a 4K HDR television?

Netflix has already announced it can stream 4K with HDR. The difference will occur on the bandwidth level. On the 66GB discs transfer speeds will be 108mbps while on the 100GB discs they should reach 128mbps. The result should be a buttery smooth playback at 60 frames per second.

But with Netflix likely to offer plenty of content by the time these discs launch, it may already be too late for Blu-ray. Especially as a new format always takes a while to adopt for content providers.

But with Sony offering a player, which it detailed as backwards compatible for older discs and TVs, perhaps there will be appeal yet. Sony will almost certainly be releasing all its movies on the new Blu-ray format at least. The format war is about to begin, again.

READ: Netflix announces High Dynamic Range coming soon for compatible HDR 4K TVs