W-VHS is a HDTV analog recording videocassette format created by JVC. The format was originally introduced in 1994 for use with Japan's Hi-Vision, an early analog high-definition television system.
W-VHS was named so because "W" means double to the Japanese.
The recording medium of W-VHS is a ½-inch metallic magnetic tape stored in a cartridge the same size as VHS. The tape can be used to store 1035i(HD) or 480i(SD), double chanel of 480i(for storing 3D programs[1])(SD2) analog signals (but not 480p, 720p or 1080i). The video signal is recorded using a method called "time compression integration" which "records separated component video, Luminance and Color signals offset by time in alternating parts of the video track".[2] Because video signals are recorded in component form instead of the s-video (Y/C) color under method used by S-VHS, standard definition image quality for W-VHS is typically much higher, due to the lack of noise caused by a chroma sub-carrier. Audio is stored in the VHS Hi-Fi or S-VHS Digital Audio formats.
W-VHS VCRs were one of the only devices consumers could use to record a Standard or High Definition video signal via an analog Y/Pb/Pr component interface. Very few devices with this capability exist, possibly due to content copyright restrictions. W-VHS has also been used for medical imaging, professional previewing, and broadcasting.
Currently, it is very difficult to find either W-VHS VCRs or tapes. Since W-VHS tapes are harder to find many people have been using the similar Digital-S (D-9) tape. While D-9 are still not that easy to find, they are more available than W-VHS tapes in certain regions. JVC Professional even recommends the use of them for W-VHS. The running time between W-VHS and Digital-S is not the same. A Digital-S tape with a length of 64 min is approx 105 min when used with W-VHS.
[edit] See also
[edit] References
[edit] External links
|
High definition media
|
|
| Media formats |
|
|
| Promoter |
|
|
| Interactivity |
|
|
| Recordable formats |
|
|
| Comparison |
|
|
| Copy prevention |
|
|
| Blu-ray Disc players |
|
|
| HD DVD players |
|
|
