<P> The Holographic Versatile Disc (HVD), described in the ECMA - 377 standard, has been in development by The Holography System Development (HSD) Forum using a green writing / reading laser (532 nm) and a red positioning / addressing laser (650 nm). It is to offer MPEG - 2, MPEG - 4 AVC (H. 264), HEVC (H. 265), and VC - 1 encoding, supporting a maximum storage capacity of 6TB . No systems corresponding to the Ecma International HVD standard have been released . Because the Blu - ray Disc format is upgradable it poses challenges to the adoption of the HVD format . 4K Blu - ray discs and players became available in the first quarter of 2016, having a storage capacity of up to 100 GB . </P> <P> Although the Blu - ray Disc specification has been finalized, engineers continue to work on advancing the technology . By 2005, quad - layer (128 GB) discs had been demonstrated on a drive with modified optics and standard unaltered optics . Hitachi stated that such a disc could be used to store 7 hours of 32 Mbit / s video (HDTV) or 3 hours and 30 minutes of 64 Mbit / s video (Ultra high definition television). In August 2006, TDK announced that they had created a working experimental Blu - ray Disc capable of holding 200 GB of data on a single side, using six 33 GB data layers . </P> <P> Also, behind closed doors at CES 2007, Ritek revealed that they had successfully developed a High Definition optical disc process that extends the disc capacity to ten layers, which increases the capacity of the discs to 250 GB . However, they noted that the major obstacle is that current read / write technology does not allow additional layers . JVC has developed a three - layer technology that allows putting both standard - definition DVD data and HD data on a BD / (standard) DVD combination . This would have enabled the consumer to purchase a disc that can be played on DVD players and can also reveal its HD version when played on a BD player . Japanese optical disc manufacturer Infinity announced the first "hybrid" Blu - ray Disc / (standard) DVD combo, to be released February 18, 2009 . This disc set of the TV series "Code Blue" featured four hybrid discs containing a single Blu - ray Disc layer (25 GB) and two DVD layers (9 GB) on the same side of the disc . </P> <P> In January 2007, Hitachi showcased a 100 GB Blu - ray Disc, consisting of four layers containing 25 GB each . Unlike TDK and Panasonic's 100 GB discs, they claim this disc is readable on standard Blu - ray Disc drives that are currently in circulation, and it is believed that a firmware update is the only requirement to make it readable to current players and drives . In December 2008, Pioneer Corporation unveiled a 400 GB Blu - ray Disc (containing 16 data layers, 25 GB each) that will be compatible with current players after a firmware update . Its planned launch was in the 2009--10 time frame for ROM and 2010--13 for rewritable discs . Ongoing development was underway to create a 1 TB Blu - ray Disc . </P>

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