CD-ROM developed by Japanese company Denon in 1982. It was an extension of Compact Disc Digital Audio, and adapted the format to hold any form of digital data, with a storage capacity of 553 MiB. CD-ROM was then introduced by Denon and Sony at a Japanese computer show in 1984. The "Yellow Book" is the technical standard that defines the format of CD-ROMs. One of a set of color-bound books that contain the technical specifications for all CD formats, the "Yellow Book", standardized by Sony and Philips in 1983, specifies a format for discs with a maximum capacity of 650 MiB.
Philips PM5544 the most commonly used test cards, with only the SMPTE bars, the BBC Test Card F and the Snell & Wilcox Zone Plate coming close to its usage. The Philips Pattern was later incorporated into other test pattern generators from Philips themselves, as well as test pattern generators from various other manufacturers. The BBC occasionally used a slightly modified version called Test Card G from 1971 until the late-1990s in conjunction with Test Card F, and although it was also used by the IBA in the 1970s it eventually abandoned the Test Card G and developed its own test card