Optical disc the DataPlay format, can have capacity comparable to that of the larger, standard compact 12 cm disc. Third-generation optical discs are in development, meant for distributing high-definition video and support greater data storage capacities, accomplished with short-wavelength visible-light lasers and greater numerical apertures. Blu-ray Disc and HD DVD uses blue-violet lasers and focusing optics of greater aperture, for use with discs with smaller pits and lands, thereby greater data storage capacity per layer. In practice, the effective multimedia presentation capacity is improved with enhanced video data compression codecs such as H.264/MPEG-4 AVC and VC-1. The following formats go beyond the
The Hitchhiker's Guide to the Galaxy Tertiary to Hexagonal Phases released on 2 October 2006 in the UK. This marks the first commercial release of any BBC radio programme in a 5.1 surround mix. The disc contains as extras: the full version of the Krikket Song, a photogallery, the original online and radio trailers, the appearance of the series on Pick of the Week, and thirty minutes of behind the scenes video in five short segments. Note that while the BBC online shop is still listing the disc as a DVD-Audio disc, their own image confirms that the disc is a lower-definition standard DVD-Video. . Since the opening of the