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Video CD (abbreviated as VCD, and also known as Compact Disc digital video) is a home video format and the first format for distributing films on standard optical discs. The format was widely adopted in Southeast Asia instead of VHS and Betamax systems. The format is a standard digital format for storing video on a compact disc. VCDs are playable in dedicated VCD players, most DVD and Blu-ray Disc players, personal computers, and some video game consoles. The Video CD standard was created in 1993 by Sony, Philips, Matsushita, and JVC and is referred to as the White Book standard. Although they have been superseded by other mediums, VCDs continue to be retailed as a low-cost video format. ==Brief history== In 1979, Philips introduced the optical LaserDisc, which was about in diameter. This disc could hold an hour of analog video along with digital audio on each side. The Laserdisc provided picture quality nearly double that of VHS tape and audio quality far superior to VHS. Philips later teamed up with Sony to develop a new type of disc, the compact disc or CD. Introduced in 1982 in Japan (1983 in the U.S.), the CD is about in diameter, and is single-sided. The format was initially designed to store digitized sound and proved to be a success in the music industry. A few years later, Philips decided to give CDs the ability to produce video, just like its Laserdisc counterpart. This led to the creation of CD Video (CD-V) in 1987. However, the disc's small size significantly impeded the ability to store analog video; thus only 5 minutes of picture information could fit on the disc's surface (despite the fact that the audio was digital). Therefore CD-V distribution was limited to featuring music videos. By the early 1990s engineers were able to digitize and compress video signals, greatly improving storage efficiency. Because this new format could hold 83 minutes of audio and video, releasing movies on compact discs finally became a reality. Extra capacity was obtained by sacrificing the error correction (it was believed that minor errors in the datastream would go unnoticed by the viewer). This format was named Video CD or VCD. VCD enjoyed a brief period of success, with a few major feature films being released in the format (usually as a 2 disc set). However the introduction of the CD-R disc and associated recorders stopped the release of feature films in their tracks because the VCD format had no means of preventing unauthorized (and perfect) copies from being made. However, VCDs are still being released in several countries in Asia, but they recently had means of copy-protection. The development of more sophisticated, higher capacity optical disc formats yielded the DVD format, released only a few years later with a copy protection mechanism. DVD players use lasers that are of shorter wavelength than those used on CDs, allowing the recorded pits to be smaller, so that more information can be stored. The DVD was so successful that it eventually pushed VHS out of the video market once suitable recorders became widely available. Nevertheless, VCDs made considerable inroads into developing nations, where they are still in use today. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Video CD」の詳細全文を読む スポンサード リンク
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