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Copy Control was the generic name of a copy prevention system, used from 2001 until 2006 on several digital audio disc releases by EMI Group and Sony BMG Music Entertainment in several regions (Europe, Canada, United States, and Australia). It should not be confused with the CopyControl computer software copy protection system introduced by Microcosm Ltd in 1989. Several types of protection existed. While basically intended as a means of copy-protecting compact discs, Copy Control discs cannot properly be referred to as CDs because the system introduces incompatible data, making the discs non-compliant with the Red Book standard for audio CDs. The system is intended to prevent digital audio extraction ("ripping") from the protected discs, and thus limit the file sharing of ripped music. The techniques used are: * Multisession (Blue Book) information is included which effectively hides the audio tracks from most CD-ROM drives; * Error-correction codes for the audio data are corrupted, which may introduce audible errors to ripped copies. * The data area of the disc usually includes DRM-restricted copies of the audio content, for which a player only exists on the dominant PC operating system, Microsoft Windows. In the Netherlands, the record labels Sony and Universal experimented with copy control until 2004. EMI kept using it until June 2006, when they dropped it. In the United States, Universal Music Group experimented with copy control on a few soundtracks in 2001 and 2002, but abandoned it afterwards; Warner Music Group has only used it in Europe on such releases as Red Hot Chili Peppers' ''Greatest Hits''. As of September 2006, Cactus Data Shield, the Macrovision technology behind Copy Control, is no longer listed as a product on Macrovision's website and has completely been abandoned in countries such as Australia.〔(Macrovision - Copy Protection, Software Licensing, and Digital Rights Management )〕 A December 2006 issue of ''Billboard'' magazine announced that EMI had decided to abandon Copy Control worldwide. Until then, it had been unclear whether EMI had completely abandoned it. There was no press release. == Background == The Copy Control protections were devised in response to the file sharing and casual CD copying that has become commonplace in recent years, allegedly causing the music industry significant losses, or "ungained" revenues. Neither issue was particularly relevant when the CD standard was introduced in the early 1980s, and thus, unlike the more recent DVDs, the CD standard specifies no inherent form of copy protection or other digital rights management. Copy Control is one of a number of attempts to apply copy protection on top of the CD standard, but since it is merely a modification of the already unrestricted standard which must still yield usable results in most CD players, the efficacy of the system varies significantly. Nevertheless, EMI's labelling of some Copy Controlled discs attempted to override consumers' statutory rights with the disclaimer "except for defective product resulting from the manufacturing process, no exchange, return or refund is permitted".〔(【引用サイトリンク】title=Campaign for Digital Rights - Corrupt audio disc information )〕 As the Copy Control discs do not conform to the requirements of the CD standard, they are not labeled with the CDDA logo, which is trademarked by Philips. A Copy Control "CD" which would not play in a car CD player was deemed "defective" in a French 2003 lawsuit, and every recent Copy Control released disc carries visible Copy Control notices stating merely compatibility with CDs and the possibility of playback problems "on some equipment, for example car CD players". Nevertheless, the discs are frequently referred to as CDs or "copy-protected CDs" in music stores and in colloquial language. 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「Copy Control」の詳細全文を読む スポンサード リンク
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