Versatile Multilayer Disc (VMD or HD VMD) is a high-capacity red laser optical disc technology designed by New Medium Enterprises, Inc.. VMD is intended to compete with the blue laser HD DVD and Blu-ray Disc formats and has an initial capacity of up to 30GB per side.
Instead of the blue-laser technology embraced by the Blu-ray and HD DVD camps, the HD VMD format uses the red-laser technology already used to create DVDs, and as a result, keeps the cost of manufacturing discs and drives low, says Eugene Levich, director and chief technology officer of New Medium Enterprises. He said that manufacturing a Blu-ray drive costs ten times as much as manufacturing a DVD or HD VMD drive, because the latter two are essentially the same drive but with different firmware.
Disc Format
Although initial details are sketchy, it appears that the format uses 5 GB per layer, similar to standard DVDs. The larger formats come from adding more layers. Whereas DVDs hold up to 2 layers per side, standard VMDs can use 4 layers, for 20 GB of storage. There are also reports of 8- and 10-layered versions which can hold 40 and 50 GB, respectively.
The Blu-ray Disc and HD DVD formats use blue-violet lasers, rather than VMD's red laser, which means they can store more information per layer. However, those formats have so far announced only 1- and 2-layered versions with experimental 4-layer versions some way ahead. Therefore, a standard 4-layer VMD stores 20 GB which is comparable to a 1-layered HD DVD (15 GB) and 1-layer Blu-ray Disc (25 GB).
Content Format
The HD VMD format is capable of HD resolutions up to 1080p which is comparable with Blu-ray and HD DVD. Video is encoded in MPEG-2 and VC-1 formats at a maximum bitrate of 40 Megabits per second. This falls between the maximum bitrates of HD-DVD (36 Mbit/s) and Blu-ray (48 Mbit/s). There is the possibility that VMD discs may be encoded with the H.264 format in the future.
The HD VMD format supports up to 7.1-channel Dolby Digital, Dolby Digital Plus, and DTS audio output, though it will not offer Dolby TrueHD or DTS Master Audio surround-sound codecs.
