The VHS ( Video Home System ) is a standard for consumer-level analog video recording on tape cassettes , introduced in 1976 by the Victor Company of Japan (JVC) . It was the dominant home video format throughout the tape media period in the late 1970s, 1980s, 1990s and early 2000s.
88-481: Magnetic tape video recording was adopted by the television industry in the 1950s in the form of the first commercialized video tape recorders (VTRs), but the devices were expensive and used only in professional environments. In the 1970s, videotape technology became affordable for home use, and widespread adoption of videocassette recorders (VCRs) began; the VHS became the most popular media format for VCRs as it would win
176-673: A TV set with a VHS mechanism, were also once available for purchase. Combo units containing both a VHS mechanism and a DVD player were introduced in the late 1990s, and at least one combo unit, the Panasonic DMP-BD70V, included a Blu-ray player. VHS has been standardized in IEC 60774–1. The VHS cassette is a 187 mm wide, 103 mm deep, and 25 mm thick (7 3 ⁄ 8 × 4 1 ⁄ 16 × 1 inch) plastic shell held together with five Phillips-head screws . The flip-up cover, which allows players and recorders to access
264-681: A common patent policy under the banner of the WSC . However, the ITU-T definition should not necessarily be considered also applicable in ITU-R, ISO and IEC contexts, since the Common Patent Policy does not make any reference to "open standards" but rather only to "standards." In section 7 of its RFC 2026, the IETF classifies specifications that have been developed in a manner similar to that of
352-402: A data format which is made public, is thoroughly documented and neutral with regard to the technological tools needed to peruse the same data. The E-Government Interoperability Framework (e-GIF) defines open standard as royalty-free according to the following text: While a universally agreed definition of "open standards" is unlikely to be resolved in the near future, the e-GIF accepts that
440-606: A definition of "open standards" needs to recognise a continuum that ranges from closed to open, and encompasses varying degrees of "openness." To guide readers in this respect, the e-GIF endorses "open standards" that exhibit the following properties: The e-GIF performs the same function in e-government as the Road Code does on the highways. Driving would be excessively costly, inefficient, and ineffective if road rules had to be agreed each time one vehicle encountered another. The Portuguese Open Standards Law, adopted in 2011, demands
528-535: A definition of open standards, which also is used in pan-European software development projects. It states: The French Parliament approved a definition of "open standard" in its "Law for Confidence in the Digital Economy." The definition is (Article 4): A clear royalty-free stance and far reaching requirements case is the one for India's Government 4.1 Mandatory Characteristics An Identified Standard will qualify as an "Open Standard", if it meets
616-517: A disadvantage. Matsushita's backing of JVC persuaded Hitachi , Mitsubishi , and Sharp to back the VHS standard as well. Sony's release of its Betamax unit to the Japanese market in 1975 placed further pressure on the MITI to side with the company. However, the collaboration of JVC and its partners was much stronger, which eventually led the MITI to drop its push for an industry standard. JVC released
704-456: A finished product. With this prototype, Sony persuaded the MITI to adopt Betamax as the standard, and allow it to license the technology to other companies. JVC believed that an open standard , with the format shared among competitors without licensing the technology, was better for the consumer. To prevent the MITI from adopting Betamax, JVC worked to convince other companies, in particular Matsushita (Japan's largest electronics manufacturer at
792-605: A full, irrevocable and irreversible way to the Portuguese State; e) There are no restrictions to its implementation. A Law passed by the Spanish Parliament requires that all electronic services provided by the Spanish public administration must be based on open standards. It defines an open standard as royalty-free, according to the following definition (ANEXO Definiciones k): An open standard fulfills
880-553: A maximum of about 430 m (1,410 ft) of tape at the lowest acceptable tape thickness, giving a maximum playing time of about four hours in a T-240/DF480 for NTSC and five hours in an E-300 for PAL at "standard play" (SP) quality. More frequently, however, VHS tapes are thicker than the required minimum to avoid complications such as jams or tears in the tape. Other speeds include "long play" (LP), "extended play" (EP) or "super long play" (SLP) (standard on NTSC; rarely found on PAL machines). For NTSC, LP and EP/SLP double and triple
968-489: A second VCR. The first version of Macrovision introduces high signal levels during the vertical blanking interval , which occurs between the video fields. These high levels confuse the automatic gain control circuit in most VHS VCRs, leading to varying brightness levels in an output video, but are ignored by the TV as they are out of the frame-display period. "Level II" Macrovision uses a process called "colorstriping", which inverts
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#17327662806361056-598: A set of principles which have contributed to the exponential growth of the Internet and related technologies. The "OpenStand Principles" define open standards and establish the building blocks for innovation. Standards developed using the OpenStand principles are developed through an open, participatory process, support interoperability, foster global competition, are voluntarily adopted on a global level and serve as building blocks for products and services targeted to meet
1144-478: A team to develop a VTR for consumers. By the end of 1971, they created an internal diagram, "VHS Development Matrix", which established twelve objectives for JVC's new VTR: In early 1972, the commercial video recording industry in Japan took a financial hit. JVC cut its budgets and restructured its video division, shelving the VHS project. However, despite the lack of funding, Takano and Shiraishi continued to work on
1232-489: A video recording standard for the Japanese consumer. The effort produced the U-matic format in 1971, which was the first cassette format to become a unified standard for different companies. It was preceded by the reel-to-reel 1 ⁄ 2 " EIAJ format. The U-matic format was successful in businesses and some broadcast television applications, such as electronic news-gathering, and was produced by all three companies until
1320-561: Is 3.335 cm / s (1.313 ips) for NTSC , 2.339 cm/s (0.921 ips) for PAL —or just over 2.0 and 1.4 metres (6 ft 6.7 in and 4 ft 7.2 in) per minute respectively. The tape length for a T-120 VHS cassette is 247.5 metres (812 ft). As with almost all cassette-based videotape systems, VHS machines pull the tape out of the cassette shell and wrap it around the inclined head drum, which rotates at 1,800 rpm in NTSC machines and at 1,500 rpm for PAL , one complete rotation of
1408-423: Is a system for storing digital information on magnetic tape using digital recording . Tape was an important medium for primary data storage in early computers, typically using large open reels of 7-track , later 9-track tape. Modern magnetic tape is most commonly packaged in cartridges and cassettes, such as the widely supported Linear Tape-Open (LTO) and IBM 3592 series. The device that performs
1496-532: Is another 1 ⁄ 60 or 1 ⁄ 50 of a second TV picture field, and so on. Thus one complete head rotation records an entire NTSC or PAL frame of two fields. The original VHS specification had only two video heads. When the EP recording speed was introduced, the thickness of these heads was reduced to accommodate the narrower tracks. However, this subtly reduced the quality of the SP speed, and dramatically lowered
1584-424: Is applied to over 550 million videocassettes annually and is used by every MPAA movie studio on some or all of their videocassette releases. Over 220 commercial duplication facilities around the world are equipped to supply Macrovision videocassette copy protection to rights owners...The study found that over 30% of VCR households admit to having unauthorized copies, and that the total annual revenue loss due to copying
1672-714: Is determined by the market. The ITU-T is a standards development organization (SDO) that is one of the three sectors of the International Telecommunication Union (a specialized agency of the United Nations ). The ITU-T has a Telecommunication Standardization Bureau director's Ad Hoc group on IPR that produced the following definition in March 2005, which the ITU-T as a whole has endorsed for its purposes since November 2005: The ITU-T , ITU-R , ISO , and IEC have harmonized on
1760-448: Is estimated at $ 370,000,000 annually. The system was first used in copyrighted movies beginning with the 1984 film The Cotton Club . Macrovision copy protection saw refinement throughout its years, but has always worked by essentially introducing deliberate errors into a protected VHS tape's output video stream. These errors in the output video stream are ignored by most televisions, but will interfere with re-recording of programming by
1848-417: Is extended/super long play ( 1 ⁄ 3 speed) which was primarily released into the NTSC market. As VHS was designed to facilitate recording from various sources, including television broadcasts or other VCR units, content producers quickly found that home users were able to use the devices to copy videos from one tape to another. Despite generation loss in quality when a tape was copied, this practice
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#17327662806361936-557: Is here meant in the sense of fulfilling the following requirements: The Network Centric Operations Industry Consortium (NCOIC) defines open standard as the following: Specifications for hardware and/or software that are publicly available implying that multiple vendors can compete directly based on the features and performance of their products. It also implies that the existing open system can be removed and replaced with that of another vendor with minimal effort and without major interruption. The Danish government has attempted to make
2024-601: Is limited to 3 megahertz, which makes higher resolutions technically impossible even with the highest-quality recording heads and tape materials, but an HQ branded deck includes luminance noise reduction, chroma noise reduction, white clip extension, and improved sharpness circuitry. The effect was to increase the apparent horizontal resolution of a VHS recording from 240 to 250 analog (equivalent to 333 pixels from left-to-right, in digital terminology). The major VHS OEMs resisted HQ due to cost concerns, eventually resulting in JVC reducing
2112-478: Is magnetic tape used for storing video and usually sound in addition. Information stored can be in the form of either an analog or digital signal . Videotape is used in both video tape recorders (VTRs) and, more commonly, videocassette recorders (VCRs) and camcorders . Videotapes have also been used for storing scientific or medical data, such as the data produced by an electrocardiogram . Some magnetic tape-based formats include: Magnetic-tape data storage
2200-422: Is magnified by the narrower tracks. The heads for linear audio are not on the spinning drum, so for them, the tape speed from one reel to the other is the same as the speed of the heads across the tape. This speed is quite slow: for SP it is about 2/3s that of an audio cassette, and for EP it is slower than the slowest microcassette speed. This is widely considered inadequate for anything but basic voice playback, and
2288-457: Is no single definition, and interpretations vary with usage. Examples of open standards include the GSM , 4G , and 5G standards that allow most modern mobile phones to work world-wide. The terms open and standard have a wide range of meanings associated with their usage. There are a number of definitions of open standards which emphasize different aspects of openness, including the openness of
2376-407: Is roughly equivalent to 333×480 pixels for luma and 40×480 pixels for chroma. 333×480=159,840 pixels or 0.16 MP (1/6 of a megapixel). PAL VHS resolution is roughly 333×576 pixels for luma and 40×576 pixels for chroma (although when decoded PAL and SECAM half the vertical color resolution). JVC countered 1985's SuperBeta with VHS HQ, or High Quality. The frequency modulation of the VHS luminance signal
2464-506: Is then published in the form of RFC 6852 in January 2013. The European Union defined the term for use within its European Interoperability Framework for Pan-European eGovernment Services, Version 1.0 although it does not claim to be a universal definition for all European Union use and documentation. To reach interoperability in the context of pan-European eGovernment services, guidance needs to focus on open standards. The word "open"
2552-462: The "format war" against Betamax (backed by Sony ) and a number of other competing tape standards. The cassettes themselves use a 0.5-inch magnetic tape between two spools and typically offer a capacity of at least two hours. The popularity of VHS was intertwined with the rise of the video rental market, with films being released on pre-recorded videotapes for home viewing. Newer improved tape formats such as S-VHS were later developed, as well as
2640-711: The GSM phones (adopted as a government standard), Open Group which promotes UNIX , and the Internet Engineering Task Force (IETF) which created the first standards of SMTP and TCP/IP. Buyers tend to prefer open standards which they believe offer them cheaper products and more choice for access due to network effects and increased competition between vendors. Open standards which specify formats are sometimes referred to as open formats . Many specifications that are sometimes referred to as standards are proprietary, and only available (if they can be obtained at all) under restrictive contract terms from
2728-467: The NTSC television standard were able to record one hour of programming at their standard tape speed of 1.5 inches per second (ips). The first VHS machines could record for two hours, due to both a slightly slower tape speed (1.31 ips) and significantly longer tape. Betamax's smaller cassette limited the size of the reel of tape, and could not compete with VHS's two-hour capability by extending
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2816-607: The New Zealand , South African and the Venezuelan governments. On the standard organisation side, the World Wide Web Consortium (W3C) ensures that its specifications can be implemented on a royalty-free basis. Many definitions of the term standard permit patent holders to impose " reasonable and non-discriminatory licensing" royalty fees and other licensing terms on implementers or users of
2904-451: The omega transport system) in a helical fashion, assisted by the slanted tape guides. The head rotates constantly at 1798.2 rpm in NTSC machines, exactly 1500 in PAL, each complete rotation corresponding to one frame of video. Two tape heads are mounted on the cylindrical surface of the drum, 180 degrees apart from each other, so that the two heads "take turns" in recording. The rotation of
2992-611: The "Simplified BSD License" as stated in the IETF Trust Legal Provisions and Copyright FAQ based on RFC 5377. In August 2012, the IETF combined with the W3C and IEEE to launch OpenStand and to publish The Modern Paradigm for Standards. This captures "the effective and efficient standardization processes that have made the Internet and Web the premiere platforms for innovation and borderless commerce". The declaration
3080-530: The 2000s. In 1956, after several attempts by other companies, the first commercially successful VTR, the Ampex VRX-1000 , was introduced by Ampex Corporation . At a price of US$ 50,000 in 1956 (equivalent to $ 560,343 in 2023) and US$ 300 (equivalent to $ 3,362 in 2023) for a 90-minute reel of tape, it was intended only for the professional market. Kenjiro Takayanagi , a television broadcasting pioneer then working for JVC as its vice president, saw
3168-495: The IETF and ITU-T explicitly refer to their standards as "open standards", while the others refer only to producing "standards". The IETF and ITU-T use definitions of "open standard" that allow "reasonable and non-discriminatory" patent licensing fee requirements. There are those in the open-source software community who hold that an "open standard" is only open if it can be freely adopted, implemented and extended. While open standards or architectures are considered non-proprietary in
3256-518: The IETF itself as being "open standards," and lists the standards produced by ANSI , ISO , IEEE , and ITU-T as examples. As the IETF standardization processes and IPR policies have the characteristics listed above by ITU-T, the IETF standards fulfill the ITU-T definition of "open standards." However, the IETF has not adopted a specific definition of "open standard"; both RFC 2026 and the IETF's mission statement (RFC 3935) talks about "open process," but RFC 2026 does not define "open standard" except for
3344-794: The United Kingdom. The United States received its first VHS-based VCR, the RCA VBT200, on August 23, 1977. The RCA unit was designed by Matsushita and was the first VHS-based VCR manufactured by a company other than JVC. It was also capable of recording four hours in LP (long play) mode. The UK received its first VHS-based VCR, the Victor HR-3300EK, in 1978. Quasar and General Electric followed-up with VHS-based VCRs – all designed by Matsushita. By 1999, Matsushita alone produced just over half of all Japanese VCRs. TV/VCR combos , combining
3432-453: The analog signal's colorburst period and causes off-color bands to appear in the picture. Level III protection added additional colorstriping techniques to further degrade the image. These protection methods worked well to defeat analog-to-analog copying by VCRs of the time. Consumer products capable of digital video recording are mandated by law to include features which detect Macrovision encoding of input analog streams, and disrupt copying of
3520-409: The cassette through the circular hole in the center of the underside, and two photodiodes are on the left and right sides of where the tape exits the cassette. When the clear tape reaches one of these, enough light will pass through the tape to the photodiode to trigger the stop function; some VCRs automatically rewind the tape when the trailing end is detected. Early VCRs used an incandescent bulb as
3608-649: The degree of openness will be taken into account when selecting an appropriate standard: The UK government 's definition of open standards applies to software interoperability, data and document formats. The criteria for open standards are published in the "Open Standards Principles" policy paper and are as follows. The Cabinet Office in the UK recommends that government departments specify requirements using open standards when undertaking procurement exercises in order to promote interoperability and re-use, and avoid technological lock-in. The Venezuelan Government approved
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3696-411: The drum moving across the tape at (a writing speed of) 4.86 or 6.096 meters per second. To maximize the use of the tape, the video tracks are recorded very close together. To reduce crosstalk between adjacent tracks on playback, an azimuth recording method is used: The gaps of the two heads are not aligned exactly with the track path. Instead, one head is angled at plus six degrees from the track, and
3784-580: The earliest optical disc format, LaserDisc ; the lack of global adoption of these formats increased VHS's lifetime, which eventually peaked and started to decline in the late 1990s after the introduction of DVD , a digital optical disc format. VHS rentals were surpassed by DVD in the United States in 2003, which eventually became the preferred low-end method of movie distribution. For home recording purposes, VHS and VCRs were surpassed by (typically hard disk –based) digital video recorders (DVR) in
3872-492: The early 1950s, magnetic tape has been used with computers to store large quantities of data and is still used for backup purposes. Magnetic tape begins to degrade after 10–20 years and therefore is not an ideal medium for long-term archival storage. The exception is data tape formats like LTO which are specifically designed for long-term archiving. Information in magnetic tapes is often recorded in tracks which are narrow and long areas of information recorded magnetically onto
3960-458: The edge label. The tapes are made, pre-recorded, and inserted into the cassettes in cleanrooms , to ensure quality and to keep dust from getting embedded in the tape and interfering with recording (both of which could cause signal dropouts) There is a clear tape leader at both ends of the tape to provide an optical auto-stop for the VCR transport mechanism. In the VCR, a light source is inserted into
4048-486: The end of the war. It was only after the war that Americans, particularly Jack Mullin , John Herbert Orr , and Richard H. Ranger , were able to bring this technology out of Germany and develop it into commercially viable formats. Bing Crosby , an early adopter of the technology, made a large investment in the tape hardware manufacturer Ampex . A wide variety of audiotape recorders and formats have been developed since. Some magnetic tape-based formats include: Videotape
4136-413: The first VHS machines in Japan in late 1976, and in the United States in mid-1977. Sony's Betamax competed with VHS throughout the late 1970s and into the 1980s (see Videotape format war ). Betamax's major advantages were its smaller cassette size, theoretical higher video quality, and earlier availability, but its shorter recording time proved to be a major shortcoming. Originally, Beta I machines using
4224-506: The following conditions: The South African Government approved a definition in the "Minimum Interoperability Operating Standards Handbook" (MIOS). For the purposes of the MIOS, a standard shall be considered open if it meets all of these criteria. There are standards which we are obliged to adopt for pragmatic reasons which do not necessarily fully conform to being open in all respects. In such cases, where an open standard does not yet exist,
4312-581: The following criteria: Italy has a general rule for the entire public sector dealing with Open Standards, although concentrating on data formats, in Art. 68 of the Code of the Digital Administration ( Codice dell'Amministrazione Digitale ) [applications must] allow representation of data under different formats, at least one being an open data format. [...] [it is defined] an open data format,
4400-418: The following steps, in this order: The erase head is fed by a high-level, high-frequency AC signal that overwrites any previous recording on the tape. Without this step, the new recording cannot be guaranteed to completely replace any old recording that might have been on the tape. The tape path then carries the tape around the spinning video-head drum, wrapping it around a little more than 180 degrees (called
4488-413: The head corresponding to one video frame. VHS uses an "M-loading" system, also known as M-lacing, where the tape is drawn out by two threading posts and wrapped around more than 180 degrees of the head drum (and also other tape transport components) in a shape roughly approximating the letter M . The heads in the rotating drum get their signal wirelessly using a rotary transformer . A VHS cassette holds
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#17327662806364576-406: The high costs of the machines and tapes. Because of the limited user base, Super VHS was never picked up to any significant degree by manufacturers of pre-recorded tapes, although it was used extensively in the low-end professional market for filming and editing. After leaving the head drum, the tape passes over the stationary audio and control head. This records a control track at the bottom edge of
4664-409: The inclined head drum, combined with the relatively slow movement of the tape, results in each head recording a track oriented at a diagonal with respect to the length of the tape, with the heads moving across the tape at speeds higher than what would otherwise be possible. This is referred to as helical scan recording. A tape speed of 1 + 5 ⁄ 16 inches per second corresponds to the heads on
4752-625: The late 1980s, but because of cost and limited recording time, very few of the machines were sold for home use. Therefore, soon after the U-Matic release, all three companies started working on new consumer-grade video recording formats of their own. Sony started working on Betamax , Matsushita started working on VX , and JVC released the CR-6060 in 1975, based on the U-matic format. In 1971, JVC engineers Yuma Shiraishi and Shizuo Takano put together
4840-444: The light source: when the bulb failed, the VCR would act as if a tape were present when the machine was empty, or would detect the blown bulb and completely stop functioning. Later designs use an infrared LED , which has a much longer life. The recording medium is a Mylar magnetic tape , 12.7 mm ( 1 ⁄ 2 inch) wide, coated with metal oxide , and wound on two spools . The tape speed for "Standard Play" mode (see below)
4928-447: The miniaturized drum with performance similar to a two head VCR with a full sized drum. No attempt was made to record Hi-Fi audio with such devices, as this would require an additional four heads to work. W-VHS decks could have up to 12 heads in the head drum, of which 11 were active including a flying erase head for erasing individual video fields, and one was a dummy used for balancing the head drum. The high tape-to-head speed created by
5016-502: The need for his company to produce VTRs for the Japanese market at a more affordable price. In 1959, JVC developed a two-head video tape recorder and, by 1960, a color version for professional broadcasting. In 1964, JVC released the DV220, which would be the company's standard VTR until the mid-1970s. In 1969, JVC collaborated with Sony Corporation and Matsushita Electric (Matsushita was the majority stockholder of JVC until 2011) to build
5104-400: The needs of markets and consumers. This drives innovation which, in turn, contributes to the creation of new markets and the growth and expansion of existing markets. There are five, key OpenStand Principles, as outlined below: 1. Cooperation Respectful cooperation between standards organizations, whereby each respects the autonomy, integrity, processes, and intellectual property rules of
5192-411: The organization that owns the copyright on the specification. As such these specifications are not considered to be fully open . Joel West has argued that "open" standards are not black and white but have many different levels of "openness". A more open standard tends to occur when the knowledge of the technology becomes dispersed enough that competition is increased and others are able to start copying
5280-415: The other at minus six degrees. This results, during playback, in destructive interference of the signal from the tracks on either side of the one being played. Each of the diagonal-angled tracks is a complete TV picture field , lasting 1 ⁄ 60 of a second ( 1 ⁄ 50 on PAL) on the display. One tape head records an entire picture field. The adjacent track, recorded by the second tape head,
5368-711: The others. 2. Adherence to Principles – Adherence to the five fundamental principles of standards development, namely 3. Collective Empowerment Commitment by affirming standards organizations and their participants to collective empowerment by striving for standards that: 4. Availability Standards specifications are made accessible to all for implementation and deployment. Affirming standards organizations have defined procedures to develop specifications that can be implemented under fair terms. Given market diversity, fair terms may vary from royalty-free to fair, reasonable, and non-discriminatory terms (FRAND). 5. Voluntary Adoption Standards are voluntarily adopted and success
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#17327662806365456-474: The playing time for an E-XXX tape in an NTSC machine, this formula is used: Since the recording/playback time for PAL/SECAM is roughly 1/3 longer than the recording/playback time for NTSC, some tape manufacturers label their cassettes with both T-XXX and E-XXX marks, like T60/E90, T90/E120 and T120/E180. SP is standard play, LP is long play ( 1 ⁄ 2 speed, equal to recording time in DVHS "HS" mode), EP/SLP
5544-419: The playing time for any given cassette will vary between the systems. To avoid confusion, manufacturers indicate the playing time in minutes that can be expected for the market the tape is sold in: E-XXX indicates playing time in minutes for PAL or SECAM. T-XXX indicates playing time in minutes for NTSC or PAL-M. To calculate the playing time for a T-XXX tape in a PAL machine, this formula is used: To calculate
5632-526: The project in secret. By 1973, the two engineers had produced a functional prototype. In 1974, the Japanese Ministry of International Trade and Industry (MITI), desiring to avoid consumer confusion , attempted to force the Japanese video industry to standardize on just one home video recording format. Later, Sony had a functional prototype of the Betamax format, and was very close to releasing
5720-647: The purpose of defining what documents IETF standards can link to. RFC 2026 belongs to a set of RFCs collectively known as BCP 9 (Best Common Practice, an IETF policy). RFC 2026 was later updated by BCP 78 and 79 (among others). As of 2011 BCP 78 is RFC 5378 (Rights Contributors Provide to the IETF Trust), and BCP 79 consists of RFC 3979 (Intellectual Property Rights in IETF Technology) and a clarification in RFC 4879. The changes are intended to be compatible with
5808-547: The quality of freeze frame and high speed search. Later models implemented both wide and narrow heads, and could use all four during pause and shuttle modes to further improve quality although machines later combined both pairs into one. In machines supporting VHS HiFi (described later), yet another pair of heads was added to handle the VHS HiFi signal. Camcorders using the miniaturized drum required twice as many heads to complete any given task. This almost always meant four heads on
5896-616: The recording time accordingly, but these speed reductions cause a reduction in horizontal resolution – from the normal equivalent of 250 vertical lines in SP, to the equivalent of 230 in LP and even less in EP/SLP. Due to the nature of recording diagonally from a spinning drum, the actual write speed of the video heads does not get slower when the tape speed is reduced. Instead, the video tracks become narrower and are packed closer together. This results in noisier playback that can be more difficult to track correctly: The effect of subtle misalignment
5984-499: The requirements for the HQ brand to white clip extension plus one other improvement. In 1987, JVC introduced a new format called Super VHS (often known as S-VHS) which extended the bandwidth to over 5 megahertz, yielding 420 analog horizontal (560 pixels left-to-right). Most Super VHS recorders can play back standard VHS tapes, but not vice versa. S-VHS was designed for higher resolution, but failed to gain popularity outside Japan because of
6072-591: The resulting specification, the openness of the drafting process, and the ownership of rights in the standard. The term "standard" is sometimes restricted to technologies approved by formalized committees that are open to participation by all interested parties and operate on a consensus basis. The definitions of the term open standard used by academics, the European Union , and some of its member governments or parliaments such as Denmark , France , and Spain preclude open standards requiring fees for use, as do
6160-465: The rotating head results in a far higher bandwidth than could be practically achieved with a stationary head. VHS machines record up to 3 MHz of baseband video bandwidth and 300 kHz of baseband chroma bandwidth. The luminance (black and white) portion of the video is frequency modulated and combined with a down-converted " color under " chroma (color) signal that is encoded using quadrature amplitude modulation . Including side bands ,
6248-485: The sense that the standard is either unowned or owned by a collective body, it can still be publicly shared and not tightly guarded. The typical example of "open source" that has become a standard is the personal computer originated by IBM and now referred to as Wintel , the combination of the Microsoft operating system and Intel microprocessor. There are three others that are most widely accepted as "open" which include
6336-462: The signal on a VHS tape can use up to 10 MHz of RF bandwidth. VHS horizontal resolution is 240 TVL , or about 320 lines across a scan line. The vertical resolution (number of scan lines) is the same as the respective analog TV standard (625 for PAL or 525 for NTSC ; somewhat fewer scan lines are actually visible due to overscan and the VBI ). In modern-day digital terminology, NTSC VHS resolution
6424-399: The spacing that exists between adjacent tracks. While good for short-term use, magnetic tape is highly prone to disintegration. Depending on the environment, this process may begin after 10–20 years. Over time, magnetic tape made in the 1970s and 1980s can suffer from a type of deterioration called sticky-shed syndrome . It is caused by hydrolysis of the binder in the tape and can render
6512-525: The standard. For example, the rules for standards published by the major internationally recognized standards bodies such as the Internet Engineering Task Force (IETF), International Organization for Standardization (ISO), International Electrotechnical Commission (IEC), and ITU-T permit their standards to contain specifications whose implementation will require payment of patent licensing fees. Among these organizations, only
6600-513: The tape length. Instead, Sony had to slow the tape down to 0.787 ips (Beta II) in order to achieve two hours of recording in the same cassette size. Sony eventually created a Beta III speed of 0.524 ips, which allowed NTSC Betamax to break the two-hour limit, but by then VHS had already won the format battle. Additionally, VHS had a "far less complex tape transport mechanism" than Betamax, and VHS machines were faster at rewinding and fast-forwarding than their Sony counterparts. VHS eventually won
6688-689: The tape unusable. Since the introduction of magnetic tape, other technologies have been developed that can perform the same functions, and therefore, replace it. Such as for example, hard disk drives in computers replacing cassette tape readers such as the Atari Program Recorder and the Commodore Datasette for software, CDs and MiniDiscs replacing cassette tapes for audio, and DVDs replacing VHS tapes. Despite this, technological innovation continues. As of 2014 Sony and IBM continue to advance tape capacity. Magnetic tape
6776-685: The tape, and one or two linear audio tracks along the top edge. Magnetic tape Magnetic tape is a medium for magnetic storage made of a thin, magnetizable coating on a long, narrow strip of plastic film . It was developed in Germany in 1928, based on the earlier magnetic wire recording from Denmark. Devices that use magnetic tape can with relative ease record and play back audio, visual, and binary computer data. Magnetic tape revolutionized sound recording and reproduction and broadcasting. It allowed radio, which had always been broadcast live, to be recorded for later or repeated airing. Since
6864-441: The tape, has a latch on the right side, with a push-in toggle to release it (bottom view image). The cassette has an anti-despooling mechanism, consisting of several plastic parts between the spools, near the front of the cassette (white and black in the top view). The spool latches are released by a push-in lever within a 6.35 mm ( 1 ⁄ 4 inch) hole at the bottom of the cassette, 19 mm ( 3 ⁄ 4 inch) in from
6952-458: The tape, which are separate from each other and often spaced apart from adjacent tracks. Tracks are often parallel to the length of the tape, in which case they are known as longitudinal tracks, or diagonal relative to the length of the tape in helical scan . There are also transverse scan and arcuate scanning, used in Quadruplex videotape . Azimuth recording is used to reduce or eliminate
7040-702: The technology as they implement it. This occurred with the Wintel architecture as others were able to start imitating the software. Less open standards exist when a particular firm has much power (not ownership) over the standard, which can occur when a firm's platform "wins" in standard setting or the market makes one platform most popular. On August 12, 2012, the Institute of Electrical and Electronics Engineers (IEEE), Internet Society (ISOC), World Wide Web Consortium (W3C), Internet Engineering Task Force (IETF) and Internet Architecture Board (IAB), jointly affirmed
7128-627: The time, marketing its products under the National brand in most territories and the Panasonic brand in North America, and JVC's majority stockholder), to accept VHS, and thereby work against Sony and the MITI. Matsushita agreed, primarily out of concern that Sony might become the leader in the field if its proprietary Betamax format was the only one allowed to be manufactured. Matsushita also regarded Betamax's one-hour recording time limit as
7216-667: The use of Open Standards, and is applicable to sovereign entities, central public administration services (including decentralized services and public institutes), regional public administration services and the public sector. In it, Open Standards are defined thus: a) Its adoption is fruit off an open decision process accessible to all interested parties; b) The specifications document must have been freely published, allowing its copy, distribution and use without restrictions; c) The specifications document cannot cover undocumented actions of processes; d) The applicable intellectual property rights, including patents, have been made available in
7304-409: The video. Both intentional and false-positive detection of Macrovision protection has frustrated archivists who wish to copy now-fragile VHS tapes to a digital format for preservation. As of the 2020s, modern software decoding ignores Macrovison as software is not limited to the fixed standards that Macrovision was intended to disrupt in hardware based systems. The recording process in VHS consists of
7392-822: The war, gaining 60% of the North American market by 1980. The first VCR to use VHS was the Victor HR-3300 , and was introduced by the president of JVC in Japan on September 9, 1976. JVC started selling the HR-3300 in Akihabara , Tokyo, Japan, on October 31, 1976. Region-specific versions of the JVC HR-3300 were also distributed later on, such as the HR-3300U in the United States, and the HR-3300EK in
7480-519: The writing or reading of data is called a tape drive . Autoloaders and tape libraries are often used to automate cartridge handling and exchange. Compatibility was important to enable transferring data. Open standard An open standard is a standard that is openly accessible and usable by anyone. It is also a common prerequisite that open standards use an open license that provides for extensibility. Typically, anybody can participate in their development due to their inherently open nature. There
7568-511: Was a major liability for VHS-C camcorders that encouraged the use of the EP speed. Color depth deteriorates significantly at lower speeds in PAL: often, a color image on a PAL tape recorded at low speed is displayed only in monochrome, or with intermittent color, when playback is paused. VHS cassettes for NTSC and PAL/SECAM systems are physically identical, although the signals recorded on the tape are incompatible. The tape speeds are different too, so
7656-555: Was invented for recording sound by Fritz Pfleumer in 1928 in Germany. Because of escalating political tensions and the outbreak of World War II, these developments in Germany were largely kept secret. Although the Allies knew from their monitoring of Nazi radio broadcasts that the Germans had some new form of recording technology, its nature was not discovered until the Allies acquired German recording equipment as they invaded Europe at
7744-531: Was regarded as a widespread problem, which members of the Motion Picture Association of America (MPAA) claimed caused them great financial losses. In response, several companies developed technologies to protect copyrighted VHS tapes from casual duplication by home users. The most popular method was Analog Protection System , better known simply as Macrovision , produced by a company of the same name. According to Macrovision: The technology
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