Blu-ray Disc
AVCREC
- See also: HD REC
AVCREC is an official[87] lower capacity variant of the Blu-ray Disc used for storing Blu-ray Disc compatible content on conventional DVD discs. It is being promoted for use in camcorders, distribution of short HD broadcast content and other cost-sensitive distribution needs. It is similar to HD REC for HD DVD.
Note that AVCREC is not the same as AVCHD content stored on DVD. The latter is a media independent format and is used presently in tapeless camcorders that record onto DVD and Blu-ray disks, as well as onto SecureDigital and MemoryStick memory cards. Playing back AVCHD content on a Blu-ray player may require modification of AVCHD directory structure, but does not require re-encoding of video files themselves.[88]
[edit] Blu-ray Disc recordable
Blu-ray Disc recordable refers to two optical disc formats that can be recorded with an optical disc recorder. BD-R discs can be written to once, whereas BD-RE can be erased and re-recorded multiple times. The theoretical maximum speed for Blu-ray Discs is about 12× as the speed of rotation (10,000 rpm) causes too much wobble for the discs to be read properly, similar to the 20× and 52× respective maximum speeds of DVDs and CDs.
Since September 2007, BD-RE was also available in the smaller 8 cm Mini Blu-ray Disc diameter size.[83][89]
On September 18, 2007, Pioneer and Mitsubishi co-developed BD-R LTH ("Low to High" in groove recording), which features an organic dye recording layer that can be manufactured by modifying existing CD-R and DVD-R production equipment, significantly reducing manufacturing costs.[90]
In February 2008, Taiyo Yuden, Mitsubishi and Maxell released the first BD-R LTH Discs,[91] and in March 2008, Sony's PlayStation 3 gained official support for BD-R LTH Discs with the 2.20 firmware update.[92]
Unlike the previous releases of 120 mm optical discs (i.e. CDs and DVDs), Blu-ray recorders hit the market almost simultaneously with Blu-ray's debut (at least in Japan).
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