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64-610: It was headed by Edgar Anstey until 1974, and from then until its demise by John W. Shepherd. Initially, it made films mostly for the British Transport Commission , but after that organisation was broken up in 1963 the majority of its films were for the British Railways Board . However it also made films for London Transport , the British Waterways Board , the travel company Thomas Cook & Son and

128-663: 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

192-557: 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

256-427: 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 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

320-586: A functional prototype of the Betamax format, and was very close to releasing 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

384-555: 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

448-492: A particular aspect of running a railway, for example running a station as seen in This is York and later Terminus . Somewhat paradoxically, many of the unit's films celebrated a quiet, unchanging image of rural Britain – with travelogues such as The Heart of England (1954), The Lake District (also 1954), Three Is Company (1959), Down to Sussex (1964) and Midland Country (as late as 1974) – while simultaneously invoking

512-486: 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

576-559: 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

640-424: 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

704-450: 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

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768-419: 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

832-422: 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

896-466: 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

960-665: The British Transport Films unit, which he headed until 1974. He also served on the Board of Governors of the British Film Institute . As a producer he was twice-nominated for an Academy Award , for Best Documentary Short Subject in 1964 for Thirty Million Letters and Best Short Subject, Live Action for Snow in 1966 Anstey died in London , England in 1987. This biographical article related to film in

1024-465: 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

1088-450: 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

1152-590: The " white heat of technology " in its other work, such as its Report on Modernisation series instigated in 1959 (renamed Rail Report in 1965). The unit won many awards over the years, including in 1965 an Academy Award nomination for Snow and in 1966 its first and only win for the film Wild Wings (the latter which had little to do with transport and concentrated on WWT Slimbridge in Gloucestershire , founded by Peter Scott (who also narrated). BTF also gave John Schlesinger an early breakthrough with

1216-538: The 1961 film Terminus , chronicling a day in the life of Waterloo station in a style highly uncharacteristic of the unit. Oscar-winning cinematographer David Watkin also got his start lighting BTF films from 1950 to 1960. BTF also produced the controversial The Finishing Line (1976) and Robbie (1979), which warned children against trespassing on railway lines and are often thought of as Public Information Films . Some 700 films were made by it over its period of operation. BTF continued to make films through

1280-469: The 1970s and early 1980s, notably chronicling the progress of the InterCity 125 ( Overture: One-Two-Five ) and, poignantly, that of the ill-fated Advanced Passenger Train , but the tide was turning against such "nationalised" industrial film units. In September 1981 BTF's film library closed, with the material being offered back to its retrospective owners. BTF ceased to exist as a full unit in 1982, although

1344-526: 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

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1408-522: The BFI (as of October 2012). The latest in the series, London on the Move, focuses on the capital's transport systems, including buses. In May 2019 BFI released a Blu-ray high-definition 2-disc collection of some of the most popular BTF films. All films have been newly digitally remastered from the film source for this release. Edgar Anstey Edgar Anstey OBE (16 February 1907 – 26 September 1987 ),

1472-628: The BTF name was still used for various British Rail internal works, many of them by then made on video , until around 1986. For a time the BTF films made for British Rail and London Transport were marketed by the Central Office of Information , but from March 1988 the now-defunct organisation FAME (Film Archive Management and Entertainment) handled the BR films on behalf of the British Railways Board, while

1536-843: The HR-3300EK in 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

1600-595: The London Transport films went to the London Transport Museum in Covent Garden . In 1996 the British Railways Board was broken up and the BR films – the bulk of the BTF archive – were acquired by the British Film Institute . In the 1980s, 1990s and early 2000s many of the films were released on video , latterly mainly by the British Film Institute (BFI) and by Beulah, which evolved out of FAME and owns

1664-520: The U-matic format. In 1971, JVC engineers Yuma Shiraishi and Shizuo Takano put together 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

1728-478: The United Kingdom is a stub . You can help Misplaced Pages by expanding it . VHS 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. Magnetic tape video recording

1792-483: The VHS project. However, despite the lack of funding, Takano and Shiraishi continued to work on 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

1856-454: 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

1920-454: 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 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

1984-409: 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

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2048-460: The coach company Thomas Tilling . Their first film was Berth 24 concerning the operation of Hull Docks. Many of the unit's films celebrated the running of Britain's nationalised railway network; early titles such as Train Time , Elizabethan Express and Snowdrift at Bleath Gill aimed to document and celebrate the achievements and hard work of railway staff and their machinery. Others documented

2112-399: 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

2176-576: 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

2240-456: 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

2304-415: 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

2368-419: 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

2432-414: 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

2496-409: 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

2560-446: 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)

2624-497: The majority stockholder of JVC until 2011) to build 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

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2688-414: The miniaturized drum required twice as many heads to complete any given task. This almost always meant four heads on 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

2752-447: 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

2816-470: 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

2880-419: 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

2944-526: The quality of the SP speed, and dramatically lowered 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

3008-612: 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

3072-525: The release rights to the BTF films made for London Transport. The British Waterways Board has also released its own library of BTF films on video, and these have latterly appeared on DVD. In recent years several have been released on DVD , with a number of films made for London Transport appearing on Beulah DVDs before the first BFI DVD compilation of BTF films appeared, after many delays, in June 2005. Ten two-disc compilations of BTF films have now been released by

3136-509: 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 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

3200-449: The second tape head, 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

3264-517: 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

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3328-441: 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

3392-611: 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

3456-409: The track, and 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

3520-444: The vertical color resolution). JVC countered 1985's SuperBeta with VHS HQ, or High Quality. The frequency modulation of the VHS luminance signal 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

3584-404: 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 , 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

3648-411: 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

3712-718: 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

3776-522: Was a leading British documentary filmmaker . Anstey was born in Watford , Hertfordshire , England in 1907, and was educated at Watford Grammar School for Boys and Birkbeck College . He spent a few years as a civil servant before starting in 1930 at The Empire Marketing Board 's film unit, under the direction of John Grierson . He was the uncredited co-director of the "seminal 1935 'social problem' film" Housing Problems . In 1949, he joined

3840-509: 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

3904-402: 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

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3968-512: Was produced by all three companies until 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

4032-523: 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

4096-528: 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 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

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