Alternative HD disc formats
HD-DVD and Blu-ray aren't the only HD disc formats out there; there's a handful of alternative formats (mostly based on red lasers) that have tried, or are still trying to get a space on that home entertainment shelf.
Forward Versatile Disc (FVD) This is a format created by Taiwan's Industrial Technology Research Institute and Taiwan Advanced Optical Storage Research Alliance. It uses a red laser, just like DVDs, but can hold up to 6GB on a single disc layer. It uses the Windows Media Video 9 and Windows Media Audio 9 Professional codecs, which allow up to 135min of HD video to be stored on each layer. You can get more information here.
HD Versatile Multilayer Disc (HD VMD) Yet another format that uses red laser technology, HD VMD has been created by a London-based company called New Medium Enterprises. HD VMD packs more layers into a DVD-sized disc than normal – three or four – with 5GB per layer. The company says it has the ability to place up to 20 layers on a single disc, to reach a potential capacity of 100GB. Current HD VMD discs use four layers and support a wide range of codes, including H.264. This is the most recent HD disc format to emerge and HD VMD products are already available on Amazon.
Enhanced Versatile Disc (EVD) This format was born in China as a way to play HD-quality content, essentially, from a DVD disc. But, supposedly, EVD players were also to be a way of bypassing licensing fees for DVD players at the time and reducing China's reliance on foreign technology. To pack HD data onto it, it was to use codecs from On2 and Coding Technologies, but later reports suggest that MPEG-4 was also considered. It was said that China wanted to switch from DVD to EVD by 2008, but that hasn't happened yet.
HVD (Holographic Versatile Disc) While it's not exactly a technology that will strictly be used for HD movies, holographic storage might be the next big thing in storage, period. By using holograms to store data on optical discs, up to 2TB of data can be stored on a single disc. And the HVD Forum's roadmap indicates that products with this capacity might be seen as early as the year 2010.