Bluray and HD DVD Technologies Main Topics Current

Blu-ray and HD DVD Technologies

Main Topics • • • Current Media Format Theory of Blu-ray Technology Integration of Blu-ray Theory of HD DVD Technology Integration of HD DVD Comparison - Which is better? Which one is more likely to catch on?

Current Media Format • CD’s – Consist of pits and lands stamped out in a spiral pattern on the disc. – A laser then reads the pits and lands. – The change from a pit to a land or a land to a pit indicates a one while no change indicates a zero.

Current Media Format Cont. • CD-RW’s – Consist of a metal phase change alloy which when heated can be to change to reflectivity • CD-R’s – Consist of a dye that is applied to the disc. – When a writing laser is shined it changes the reflectivity.

Current Media Format Cont. • DVD’s – Also contain pits and lands. – Are more highly compact than a CD. – Special laser is needed to read them.

High Definition • To better understand the need for media formats with greater storage lets briefly describe what High Definition is. • Your regular TV signal has about 480 pixel lines, but HD has about 1280 pixel lines that go across your TV • Because of this difference the bandwidth of HD is about 5 times greater than standard video. • Currently a standard movie takes up almost an entire DVD so we need something that’s almost 5 times that. • Enter Blu-ray and HD DVD technologies….

Blu-ray Technology • Name – Derived from the blueviolet laser used to read and write data. – Developed by the Bluray Disc Association with more than 180 members. • Dell • Sony • LG

Blu-ray Technology Cont. • Data capacity – Because Blu-ray uses a blue laser(405 nanometers) instead of a red laser(650 nanometers) this allows the data tracks on the disc to be very compact. – This allows for more than twice as small pits as on a DVD.

Blu-ray Technology Cont. • Data Capacity Cont. – Because of the greatly compact data Blu-ray can hold almost 5 times more data than a single layer DVD. Close to 25 GB! – Just like a DVD Blu-ray can also be recorded in Dual-Layer format. This allows the disk to hold up to 50 GB!! – Because the polycarbonate layer of the Blu-ray disc is so much larger than a DVD because the recording layer is so much smaller it can have even more than two layers.

Blu-ray Technology Cont. • Writing Data – Blu-ray uses a combination of two lenses to greatly shrink the laser to read the data. – This also allows for higher data rate transfer close to 36 mbps. • It could record 25 GB of data in an hour an a half.

Blu-ray Technology Cont. Formats • BD-ROM (read-only) - for pre-recorded content • BD-R (recordable) - for PC data storage • BD-RW (rewritable) - for PC data storage • BD-RE (rewritable) - for HDTV recording

Blu-ray Integration • Blu-ray discs are able to record HD without any signal loss. – Single layer up to 2 hours of HD video – Dual layer up to 4. 5 hours of HD video

Blu-ray Integration Cont. • Security – Blu-ray discs are better armed than current DVDs. They come equipped with a secure encryption system -- a unique ID that protects against video piracy and copyright infringement.

HD DVD Technology • Name – Obviously comes from the term High Definition – Developed by Toshiba and NEC

HD DVD Technology Cont. • Data Capacity – HD DVD uses close to the same blue laser that the Blu-ray disc does. It is also 405 nanometers wide. – Thus allows for data to be greatly compressed.

HD DVD Technology Cont. • Data Capacity Cont. – Single Layer Disc • 15 GB – Dual Layer Disc • 30 GB

HD DVD Technology Cont. Formats • HD DVD (read-only) - for pre-recorded content • HD DVD-R (recordable) - for PC data storage • HD DVD-RAM (rewritable) - for HDTV recording

HD DVD Integration • Compatibility – Because a lot of homeusers don’t yet have a high definition Television the makers of the HD DVD disc made it backwards compatible by using the twin format scheme.

HD DVD Integration Cont. • Compatibility Cont. – But what about dual layer? ? – In order to accommodate for the needs of the storage capacity of the dual layer format the makers designed the combination format.

HD DVD Integration Cont. • Security – Uses the same security feature as Blu-ray. – Both Blu-ray and HD DVD makers said would be extremely hard to pirate with this security feature. – Eight days after HD DVD discs hit the market a hacker called muslix 64 reportedly cracked the security feature.

HD DVD vs Blu-ray • Both formats use blue lasers rather than red. • Both have the same options for video and audio compression. • Blu-ray offers significantly more storage space -- 50 GB on a dual-layer disc versus HD-DVD's 30 GB. • The DVD Forum, which creates DVD standards, has approved HD-DVD and has not approved Blu-ray. • HD-DVD is less expensive than Blu-ray. • HD-DVDs can be produced on existing equipment, and Blu-ray discs can't.