Wednesday, July 13, 2005

High Definition DVDs: a Beta vs. VHS Redux?

In the 1980's two competing video formats fought it out in American living rooms. Betamax, released by Sony in 1975, was arguably the better technology. In fact many musicians used the technology to create digital recording a decade before digital recording became commonplace. However VHS, released by JVC in 1976, allowed significantly longer recording times (the original Beta format was limited to one hour, VHS could record 6).

A new war is looming between two incompatible types of high-definition video discs scheduled to hit the market later this year. Hollywood studios have committed to releasing scores of high-definition DVD movies later this year. Two camps backing incompatible next-generation technologies, led respectively by Sony and Toshiba, have as yet failed to agree on a way to unify their products.

The two technologies are known as HD DVD and Blu-Ray. The core difference between the two formats lies with a single aspect of the disc — a thin layer of plastic that sits just above the metal surface on which data is written. An HD DVD disc calls for a 0.6 millimeter coating, while a Blu-ray disc requires 0.1 millimeters. Blu-ray's thinner coating is the secret behind the disc's higher capacity. Since the laser travels through a thinner layer of resin, it's able to focus more sharply and write 67 percent more data onto the disc itself.

Sony's Blu-ray gets its name from the blue laser that, in addition to other techniques, allows it to store substantially more data on the same sized disc than a DVD. One single-layer Blu-ray disc can hold about 25 GB or over two hours of HD video plus audio, and the dual-layer disc can hold approximately 50 GB. The have already demonstrated 200 GB eight-layer technology. Blu-ray is supported by Apple; Dell; Hewlett Packard; Hitachi; LG; Mitsubishi; Panasonic (Matsushita Electric); Pioneer; Samsung; Sharp; Sony; Twentieth Century Fox; and Walt Disney.

Toshiba's HD DVD has a single layer capacity of 15 GB and a dual-layer capacity of 30 GB. HD DVD media is less expensive to manufacture than Blu-ray Disc which require re-tooling of DVD disc production lines. HD DVD players can also rely on some of the same technology as conventional DVDs, making it easier to build players that can handle both generations of disc. HD DVD is supported by Canon; Fuji; NEC; Onkyo; Paramount; Ricoh; Sanyo; TEAC; Toshiba; Warner Home Video.

If history is any indicator of the future, Sony may have learned its lesson and Blu-ray's larger recording capacity will win out. Their plan to include a Blu-ray drive in its PlayStation 3 should give it a strong foothold.


HD DVD Promotion Group
Blu-ray Disc Association Sphere: Related Content

Wednesday, July 06, 2005

Bluetooth: Bringing Devices and Information Together

Bluetooth ® is a wireless standard developed by the Bluetooth Special Interest Group, an industry association of electronics manufacturers. This standard allows different types of wireless devices such as headsets, PCs, mobile phones, keyboards, handhelds, etc. to communicate with each other without the need for extensive setup by the user. While the technology has been slow to develop, more and more mobile phone and car manufacturers are including Bluetooth. So, the time for Bluetooth is here.

Bluetooth-enabled devices begin communicating immediately when two or more devices are within range of each other by periodically broadcasting inquiry messages. If there is a response the originator of the inquiry becomes the Master unit and the responder becomes the Slave. After this initial contact, the Master sends the Slave information about how they will communicate including the initial frequency and phase. This results in the creation of a series of ad hoc networks are called Piconets, with a collections of Piconets forming Scatternets. In each case, the connections are peer-to-peer.

Bluetooth technology uses the 2.45 GHz (gigahertz) frequency along with other wireless technologies such as 802.11 (Wi-Fi) and can coexist because they use vastly different standards. A Bluetooth device will never mistake Wi-Fi as a Bluetooth transmission. Bluetooth devices transmit a 1 mW (milliwatt) signal that travels about 33 feet. The technology employs "spread-spectrum frequency hopping" in which it regularly switches transmitting among 79 individual random frequencies. The switch happens 1,600 times per second, so it's improbable that two Bluetooth devices will be using the same frequency at the same time and allows different Bluetooth devices running in close proximity at the same time without interfering with each other.

Academic and public libraries could reap the benefits of a Bluetooth-enabled network. Librarians at the reference desk assisting patrons in their research could transmit the results directly to the customer's PDA, avoiding the need to print the documents. Information that is transmitted could include rights and allowable use info, provenance, indexing and cataloging info, as well as digital media content associated with that item. Customers connected to the library network could share information electroncially in ad hoc user groups.

An instructor could turn student Bluetooth devices into instant workstation and create an on the fly computer lab. A Bluetooth cell phone or PDA could be used as PC remote control for professional presentations. Bluetooth printers could be placed throughout the library for those who wish to obtain printouts from mobile devices without requiring network cables and eliminates the line-of-sight problems with using infrared printers. Visually impared customers could use a Bluetooth pen reader that scans and speaks text from printed materials into a headset.

The technology received its name from Harald Bluetooth, son of Denmark's first king, Gorm the Old. The Danish word for blue, blÄ, also meant dark and the words for man, mand, and tooth, tand, and sound much the same. At the time of his rule, somewhere between 940 and 980 AD, southern Sweden was part of Denmark. In southern Sweden is Lund, the city in which Ericsson developed the Bluetooth technology. According to Ericsson, "One of his skills was to make people talk to each other....," and hence the choice of Bluetooth.


Mott Allen, Maryellen. Bluetooth Bites Information Retrieval. ONLINE, May 2001

Guscott, John. These Emerging Technologies Will Change Public Libraries Library Futures Quarterly, May 2001. Sphere: Related Content