HD DVD

What is an HD DVD? An HD DVD or the High Definition Digital Versatile Discs, are actually those high-density optical disc formats that are designed primarily for storing data and other high-definition videos. The HD DVD discs are designed as successors for the standard DVD formats. These discs can store three times more than its predecessors. While the standard DVD formats can store at least 4.7GB for a single layer, the HD DVD can store up to 15GB per layers. The HD DVD standards were jointly developed and designed by Toshiba and NEC. DVD Forum voted the HD DVD in November 19, 2003 as the predecessor of the standard DVD. Currently, the specific versions for both the HD DVD-Rom and the HD-DVD Rewritable are the version 1.0. For the HD-DVD-R, its specification is version 0.9, while the HD DVD-RAM is not yet finalized. The very first HD DVD-ROM drives were launched later part of 2006. However, there are still no HD DVD recorders that are for sale.

Disc Structure of the HD-DVD- The HD-DVD has a single and dual layer capacities, 15GB and 30GB respectively. Likewise, the DVD-RAMs have single-layer capacities of 20GB, while the dual-layer capacities are still undecided. Similar with the original DVD formats; data layers of HD DVD discs are 0.6mm below the main surface, protecting physically the data layers against damages. The numerical apertures of an optical pick-up head are generally 0.65, compared from the 0.6 from DVD. All the HD DVD players likewise, are said backward compatible with the DVD and the CD.

Hybrid Formats- There are generally two main types of hybrid formats that contain standard DVD-Video formats for playback on regular DVD players as well as the HD DVD videos for those high definition playbacks of DVD Players. The combo discs, usually dual sided discs with one side a DVD and the other an HD DVD, each of the side can have up to two layers. The twin discs, which are single sided discs, contain three layers, the two layers of which are dedicated for the DVD or the HD DVD. These types of hybrid discs make shelf space managements and retail marketing easier.

The HD DVD formats are also applied to the current red laser DVDs that offer lower-cost options for the distributors. These types of discs are called the “3x DVDs” because they are capable of storing three times more than the bandwidth of those regular DVD-videos. A 3x DVD is physically similar to a regular DVD, which perhaps explains why its cost is lower for a physical media. While a 3x DVD provides similar high definition contents, playbacks are somewhat limited. For example, the 8.5GB DVD can easily fit approximately eight five minutes of videos that are encoded with the VC-1 and the AVC at average bitrates of 13Mbits per second. This means to say that they are suitable for those subjects like home movies and training videos, but not fir for those conventional wide release studio movies. Technically, it is possible for users to create an HD DVD compatible disc using affordable DVD-R and DVD+R media. At least, one guide has already been written that can help users through authoring these said discs.

Thought the HD DVD standards are not yet finalized, engineers have continued working for more advanced technologies. During the annual Consumer Electronics Show last January 7,2007, Toshiba has announced that they have designed HD DVDs that has 17GB layers. They also demonstrated triple layers of 51GB discs. The company aims to secure final approvals of these new discs anytime this year. However, there is no guarantee that those triple-layer formats can work well with the existing players today.

As far as digital technology is concerned, it is pretty obvious that it is definitely improving. With the birth of the latest devices and gadgets, no wonder more and more people are trying to learn more about the latest technologies.