Digital-S, later known as D-9, is a professional digital videocassette format created by JVC in 1995. It is a direct competitor to

Sony is a Japanese multinational conglomerate (company), conglomerate headquartered at Sony City in Minato, Tokyo, Japan. The Sony Group encompasses various businesses, including Sony Corporation (electronics), Sony Semiconductor Solutions (i ...

's Digital Betacam. Its name was changed to D-9 in 1999 by the SMPTE. It was used to a small extent in Europe and Asia and saw some use in the US, notably by the Fox News Channel, but was a commercial failure compared with Digital Betacam. It was superseded by high-definition tapeless formats.

Technical details

The Digital-S tape itself uses a much higher quality metal particle formulation. The recording system is digital and for video uses DV compression at a 50 Mbit/s bitrate. Video is recorded in 4:2:2 component format at a variety of

standard-definition Standard-definition television (SDTV; also standard definition or SD) is a television system that uses a resolution that is not considered to be either high-definition television, high or enhanced definition. ''Standard'' refers to offering a ...

resolutions, in either 4:3 or 16:9 aspect ratios. Audio is recorded as 16-bit/48 kHz PCM with up to four separate channels. The tape is 1/2 inch wide, the helical scan head drum is 62 mm in diameter, and the video tracks, which are read by the video heads in the head drum, are 20 microns wide. Video quality is generally very high; at standard definition, D-9's quality is comparable with Digital Betacam. The BR-D51U model is additionally capable of analogue S-VHS playback.

HD recording

For high-definition video recording, JVC developed an extension to D-9 called D-9 HD, using twice the number of recording heads to record a 100 Mbit/s video bitstream at resolutions of 720p60, 1080i60 and 1080p24. This variant can also record 8 channels of PCM audio at 16 bits and 48 kHz. The higher data rate and increased tape speed mean that the recording time of any given cassette would be halved. D-9 HD, based on specifications, would have been higher quality than Sony HDCAM but lower than Sony HDCAM SR; no objective tests were made comparing these formats. It is not clear whether this proposed format was ever manufactured or sold.

Additional information

Although D-9 uses the same video codec as DV, the video bitrate of D-9 is significantly higher than that of the

prosumer A prosumer is an individual who both consumes and produces. The term is a portmanteau of the words '' producer'' and ''consumer''. Research has identified six types of prosumers: DIY prosumers, self-service prosumers, customizing prosumers, co ...

format. DVCPRO achieves bitrate parity with D-9 and D-9 HD, but has a slower tape speed, making it less reliable. Some of the D-9

television studio A television studio, also called a television production studio, is an installation room in which video productions take place, either for the production of live television and its recording onto video tape or other media such as SSDs, or for ...

gear is capable of recording with Sel-Sync or pre-read and is provided with four-channel audio like Digital Betacam.

Serial digital interface Serial digital interface (SDI) is a family of digital video Interface (computing), interfaces first standardized by SMPTE (The Society of Motion Picture and Television Engineers) in 1989. For example, ITU-R BT.656 and SMPTE 259M define digital ...

s (SDI) are also provided. A dockable recorder, the JVC BR-D40, attached to a variety of cameras, and there was a one-piece camcorder, the JVC DY-70U.

References

{{High definition media Video storage Videocassette formats Audiovisual introductions in 1995