Compatible with all digital broadcasts in the world including Japanese digital

high-definition broadcasts, and DTV broadcasts in the U.S.A.

The technical format specifications of D-VHS were standardized in April 1996, and all specifications of the 3 modes that were planned, including the STD (standard) mode which was released in the U.S. in December 1997, have now been finalized. Moreover, following on the already-released exclusive D-VHS cassette DF-300, development of the DF-420 cassette which enables extended-time recording has been completed.

Through these standardizations, D-VHS has now become compatible with all types of digital broadcasts in the world including new digital high-definition broadcasts that will begin in earnest in the 21st century, and it will evolve further as a new recording medium capable of broadening its utility as a home data server in the digital multimedia era.

<Main characteristics of HS mode>

1. Capable of recording high-definition (HD) digital images and multi-channel broadcasts.

2. Achieves a 28.2 Mbps data rate.

3. Enables recording of 3.5 hours of high-definition digital broadcasts (using DF-420 cassette).

<Main characteristics of LS mode>

1. Achieves 49 hours max. recording of images and sound.

2. 4 selectable data rates 2.0Mbps (49-hour recording), 2.8Mbps (35-hour recording), 4.7Mbps (21-hour recording), 7.0Mbps (14-hour recording) assure compatibility with a wide range of future applications.

<Main characteristics of D-VHS>

1. Enables bit stream recording of digital broadcasts, in addition to analog recording of conventional broadcasts.

2. Takes advantage of the characteristics of tape as a medium to provide extremely large capacity digital data storage.

3. Maintains compatibility with conventional VHS by allowing recording and playback of the enormous amount of VHS software available as well as stored around the world.

4. Can readily evolve and spread as a household device due to the possibility of utilizing current VHS technologies, parts and manufacturing facilities.

*As the digital interface, IEEE 1394 has been adopted by virtue of its wide ranging and mutual system connection abilities among digital products in the multimedia era.

<D-VHS recording modes>



Companies which have provided technical advice for D-VHS format:

Hitachi, Ltd.

Matsushita Electric Industrial Co., Ltd.

Philips Electronics N.V.

What is "Bit stream recording ?

Bit stream recording is a method of recording processed (e.g. compressed or scrambled) signals, such as those of digital broadcasts, on a tape directly as digital data, and outputting them in the same state as they were input. Therefore a bit stream recording unit does not incorporate functions like analog-to-digital (A/D) conversion, digital-to-analog (D/A) conversion, digital compression/decompression, or descrambling. So, video and audio signals cannot be produced using that unit alone. To reproduce video and audio signals, the bit stream data must go through a digital broadcast receiver's circuits that convert the digital data to video and audio signals.