HD DVD BD9 formats. HD Rec is an extension of the HD DVD format for recording HD content on regular red laser DVD-Rs/DVD-RWs using H.264/MPEG-4 AVC compression. It was approved by the DVD Forum on September 12, 2007 It is comparable to Blu-ray Disc's AVCREC. The China Blue High-definition Disc (CBHD), a high-definition optical disc format, was based upon the HD DVD format. Like the HD DVD, CBHD discs have a capacity of 15 GB single-layer and 30 GB dual-layer and can use existing DVD production lines. Unlike the HD DVD format, industry support for this format has grown steadily. HD DVD
Optical disc a protective layer read by a focused laser beam , filed 1972, issued 1991. Kramer's physical format is used in all optical discs. In 1975, Philips and MCA began to work together, and in 1978, commercially much too late, they presented their long-awaited Laserdisc in Atlanta. MCA delivered the discs and Philips the players. However, the presentation was a commercial failure, and the cooperation ended. In Japan and the U.S., Pioneer succeeded with the videodisc until the advent of the DVD. In 1979, Philips and Sony, in consortium, successfully developed the audio compact disc. In 1979, Exxon STAR Systems in