Video & VHS
VideoThe video cassette recorder (or VCR) is a device that uses magnetic tape to record audio and video so it can be played back later. It has its own tuner. It can be programmed to record the signal on a particular channel during a particular time interval.
Before the advent of the VCR proper, portable video recorders using half-inch wide tape on 7 inch reels were marketed by Sony. These did not have timers, and were mainly used by schools and colleges to record educational programmes, and by businesses as a means of distributing training films. Even earlier, in the 1950s, British enthusiasts could buy home kinescope kits which allowed the filming of TV shows on 16mm film.
In the early 1970s the Dutch electronics company Philips developed a VCR system that used square cassettes with a recording time of one hour. The machines were equipped with crude timers that used rotary dials. The machines were expensive and the system never caught on.
It was not until the late 1970s, when European and Japanese companies developed more technically advanced machines with more accurate electronic timers and greater tape duration, that the VCR started to become a mass market consumer product. By 1980 there were three competing technical standards, with different, physically incompatible tape cassettes.
One, the Video 2000 or V2000 system, also from Philips dropped out of the running quite quickly. It worked well, and gave a good quality recording and playback, as it used piezoelectric head positioning to dynamically adjust the tape tracking. It was also notable in that its cassettes had two sides, like a record or audio cassette. However, V2000 hit the market after the other two rivals, and managed only limited sales in Europe before vanishing.
The two major standards were Sony's Betamax (also known as Betacord or just Beta), and JVC's VHS. Betamax was generally reckoned to make and play slightly better quality recordings, but VHS rapidly overtook it in sales. As more VHS recorders came into use, and more VHS films became available, network effects eventually Betamax was squeezed out of the consumer market; though a related system called Betacam still remains in use for high quality professional recording equipment. Some accounts claim that VHS won because initially allowed for twice the recording time. Others attribute the success of VHS to the greater availability of pornography on that medium, reflecting the long standing tradition of pornography being the driving force for the takeup of new media (the Internet being another obvious example).
In the late 1990s and early 2000s, DVD gradually overtook the VCR as the most popular format for playback of prerecorded video. For home vidoe recording, both Personal Video Recorders(such as Tivo and Replay TV) and DVD recorders are becoming popular, although neither has yet to supplant the VCR. In fact, Tivo cooperates well with VCRs which can be used to archive PVR recordings. However, the introduction of recordable DVDs with sufficient recording capacity on to the regular market with their advantage of random access could spell the doom of the VCR once the price comes down significantly.
Macrovision caused the functionality of the video cassette recorder to be greatly reduced by adding fading to recorded video, preventing the copy of DVDs. All unmodified DVD players include this protection, though there now appears to be a minor industry in some countries modifying them to disable Macrovision encoding, and "video clarifier" boxes sold at electronics stores will often get rid of the Macrovision signal.
The S-VHS format has been introduced in an attempt to breathe new life into the aging VCR technology, but it has not gained sufficient momentum in the consumer market due to the new digital video formats.
VHSThe Video Home System (VHS) is the recording and playing standard for video cassette recorders (VCRs), developed by JVC and launched in 1976.
It became the standard in the 1980s after competing with Sony's Betamax and, to a lesser extent, Philips's Video 2000.
A VHS-cassette contains a long 1/2 inch magnetic tape which is wound from one of two spools to the other, allowing it to slowly pass by the reader head of the video cassette recorder.
Several improved versions of VHS exist, most notably S-VHS, an improved analog standard, and D-VHS, which records digital video onto a VHS form factor tape.
VHS-C tapes (C for compact) was used in camcorders and could be played back in a regular VHS player with an adapter.
VHS tapes have an approx. 3 MHz horizontal resolution and 250 lines vertical resolution.
Although VHS officially stands for Video Home System some early reports claimed that the initials originally stood for Victor (Company) Helical Scan system.