DVD MEDIA DUAL LAYER
DVD media dual layer require players to spin the disc in the opposite direction in order to read the specially encoded information. This data exists on a second physical layer that is semi-transparent, but older players are not always able to pick up on it, and even those that do will exhibit a slight pause or "hiccup" at the moment of transition, confusing consumers so much that many companies have actually resorted to printed and even onscreen advisories for their DVD media dual layer discs, with the intention of pre-empting any worries by informing viewers that such incidents are entirely normal for DVD media dual layer playback.
That, unforunately, is not the only instance of consumer confusion when it comes to the DVD format. DVD media dual layer discs are just the latest in a long parade of quirky incidents that could have inhibited the widespread adoption of the DVD. For even though they have been around for well over a decade now, DVDs still occasion some confusion for the common consumer of home electronics. Within only three years of their debut a challenge arose to threaten the format’s very survival. Today’s situation is somewhat similar, what with the introduction of extensions such as Blu-ray DVD and HD-DVD. Third in a series that will survey everything related to DVDs, this article will examine one of these competing formats, Blu-ray.
Blu-ray DVD, or Blu-ray Disc (BD), is a next-generation technology for optical discs that was developed by a consortium of industry leaders made up of a range of companies from computer heavy-weights like Apple and Dell to consumer electronics giants such as Sony, Samsung, and Philips. The format was invented to allow for the recording, rewriting, and of course playback of high-definition video, defined as either 720p or 1080i/p. Blu-ray Discs can hold up to 25GB on a single layer, or 50GB on dual-layered discs, some five and ten times the capacity of a standard DVD. Advanced audio and video codecs provide for better, more intelligent processing of signals to present an unprecedented experience.
This format was dubbed “Blu-ray” because of the blue-violet laser used to read and write data; traditional optical disc technologies from CDs to DVDs±RW have employed red lasers with longer wavelengths instead. The shorter wavelength of Blu-ray makes it possible to focus the laser much more accurately, thus allowing for ever-smaller pits of data to be physically encoded into the surface of the disc. More tightly packed data means increased storage efficiency. Indeed, Pioneer has even been able to push the technological envelope with a 400GB disc!
However, Blu-ray products can be easily rendered backwards-compatible through the use of a combination pickup unit. The format is supported by almost two hundred of the world’s top technology and entertainment companies. It is the widely recognized successor to today’s standard DVD format, after Toshiba bowed out of the competition and formally withdrew support for HD-DVD. Toshiba had been the biggest promoter of HD-DVD, but its hand had been forced by the earlier withdrawal of support by industry titans like Warner Brothers, Netflix, and Wal-Mart. With so many big names switching allegiances, the would-be format wars never really materialized. Ironically, the first HD-DVD discs available in the United States were released by Warner Brothers a month after the formal end of their support for HD-DVD.