Blue-ray disc:
Capacity of one single layer BD is 25 to 27GB which was capable to record one 4 hours high definition movie. Sony group claim that it only takes about 50mins to record it under the 6X speed. And double layer BD’s capacity is 46 to 54GB which was capable to record one 8 hours high definition movie. Other BD-Ray Capacity up to 100GB or 200GB is 4 layers and 8 layers.
There are two forms of BD which are BD-R (Single time writable) and BD-RE (Rewritable)
BD Applications:
High Definition Television Recording
High Definition Video Distribution
High Definition Camcorder Archiving
Mass Data Storage
Digital Asset Management and Professional Storage
The Blue-ray Disc format was designed to offer the best performance and features for a wide variety of applications. High Definition video distribution is one of the key features of Blue-ray Disc, but the format's versatile design and top-of-the-line specifications mean that it is suitable for a full range of other purposes as well.
High Definition Television Recording:
H igh Definition broadcasting is vastly expanding in the U.S. and Asia. Consumers are increasingly making the switch to HDTV sets to enjoy the best possible television experience. The Blue-ray Disc format offers consumers the ability to record their High Definition television broadcasts in their original quality for the first time, preserving the pure picture and audio level as offered by the broadcaster. As such it will become the next level in home entertainment, offering an unsurpassed user experience. And since the Blue-ray Disc format incorporates the strongest copy protection algorithms of any format or proposal to date, the format allows for recording of digital broadcasts while meeting the content protection demands of the broadcast industry.
High Definition Video Distribution:
Due to its enormous data capacity of 25 to 50 GB per (single-sided) disc, the Blu-ray Disc format can store High Definition video in the highest possible quality. Because of the huge capacity of the disc, there is no need to compromise on picture quality. Depending on the encoding method, there is room for more than seven hours of the highest HD-quality video. There is even room for additional content such as special features and other bonus material to accompany the High Definition movie. Furthermore, the Blue-ray Disc movie format greatly expands on traditional DVD capabilities, by incorporating many new interactive features allowing content providers to offer an even more incredible experience to consumers. An Internet connection may even be used to unlock additional material that is stored on the disc, as there is enough room on the disc to include premium material as well.
High Definition Camcorder Archiving:
As the market penetration of High Definition TV sets continues to grow, so does the demand of consumers to create their own HD recordings. With the advent of the first HD camcorders, consumers can now for the first time record their own home movies in a quality level unlike any before. As these camcorders are tape-based, consumers cannot benefit from the convenience and direct access features they are used to from DVD players and recorders. Now, the Blue-ray Disc format, with its unprecedented storage capacity, allows for the HD video recorded with an HD camcorder to be converted and recorded on a Blue-ray Disc. When the HD content is stored on a Blue-ray Disc, it can be randomly accessed in a way comparable to DVD. Furthermore, the disc can be safely stored for many years, without the risk of tape wear.
Mass Data Storage:
In its day, CD-R/RW meant a huge increase in storage capacity compared to traditional storage media with its 650 MB. Then DVD surpassed this amount by offering 4.7 to 8.5 GB of storage, an impressive 5-10 x increase. Now consumers demand an even bigger storage capacity. The growing number of broad band connections allowing consumers to download vast amounts of data. As well as the ever increasing audio video and photo capabilities of personal computers have led to yet another level in data storage requirements. In addition, commercial storage requirements are growing exponentially due to the proliferation of e-mail and the migration to paperless processes. The Blue-ray Disc format again offers 5-10 x as much capacity as traditional DVD resulting in 25 to 50 GB of data to be stored on a single rewritable or recordable disc. As Blue-ray Disc uses the same form factor as CD and DVD, this allows for Blue-ray Disc drives that can still read and write to CD and DVD media as well.
Digital Asset Management and Professional Storage:
Due to its high capacity, low cost per GB and extremely versatile ways of transferring data from one device to another (because of Blue-ray Disc's extremely wide adoption across the industry), the format is optimized for Digital Asset Management and other professional applications that require vast amounts of storage space. Think of medical archives that may contain numerous diagnostic scans in the highest resolution, or catalogs of audiovisual assets that need to be instantly retrieved in a random manner, without the need to "restore" data from a storage carrier. One Blue-ray Disc may replace many backup tapes, CDs, DVDs or other less common or proprietary storage media. And contrary to network solutions, the discs can be physically stored in a different location for backup and safekeeping.
ROM-Mark:
The ROM-Mark is a physical layer technology intended to prevent unwanted reproduction of data on Blue-ray discs. The ROM Mark is a unique identifier embedded in pre-recorded ROM media discs such as movies, music and games. The ROM Mark can be mastered only with equipment available to licensed BD-ROM manufacturers.
Reference Wikipedia:
Calculation of Blue-ray disc & DVD’s capacity:
Normally manufacturers used decimal system to calculate capacity, 4.7GX1000=4.700MB, 4.700MBX1000=4.700.000KB.
But computer used 1024KB as 1 MB. So the effective capacity is 4.700.000÷1024=4589.84375MB,4589.84375MB÷1024=4.48GB.
Although the maximum capacity of DVD & BD are 4.7GB and 25GB.But our suggested recordable capacity are 4.4GB and 22.65GB. Since players access the data from inside of disc to outside. And the vibration rate of outside of disc is higher, so there will be more chances of failure if you record the data volume more than our suggested capacity.
BLUE RAY:
Blue-ray, also known as Blue-ray Disc (BD) is the name of a next-generation optical disc format. The format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data. The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc.
