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ETP-1
ETP-1 (or Electronic Test Pattern One) was a test card designed and used by the Independent Broadcasting Authority (IBA). After test transmissions from the IBA's Engineering Regional Operations Centre (ROC) in Croydon from 1978 it was phased in on ITV over a period starting from 1979, replacing, in different ITV regions: Test Card F, Test Card G and full screen height EBU colour bars. After ITV went 24 hours in 1988, the card ceased to be seen on the channel. It was used for both 625-line PAL and 405-line monochrome broadcasts. It was also seen extensively on both Channel 4 and S4C during both their pre-launch tests and their downtime of those channels, due to their limited hours early on. After launch, it was alternated with in-vision teletext services from ORACLE and 4-Tel on View/ Sbectel. On these channels, it was captioned either IBA:CH4 or IBA:S4C, with lines above and below this indicating the card was being generated by the channel, the absence of these lines meant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ETP-1 Recreation
ETP-1 (or Electronic Test Pattern One) was a test card designed and used by the Independent Broadcasting Authority (IBA). After test transmissions from the IBA's Engineering Regional Operations Centre (ROC) in Croydon from 1978 it was phased in on ITV over a period starting from 1979, replacing, in different ITV regions: Test Card F, Test Card G and full screen height EBU colour bars. After ITV went 24 hours in 1988, the card ceased to be seen on the channel. It was used for both 625-line PAL and 405-line monochrome broadcasts. It was also seen extensively on both Channel 4 and S4C during both their pre-launch tests and their downtime of those channels, due to their limited hours early on. After launch, it was alternated with in-vision teletext services from ORACLE and 4-Tel on View/ Sbectel. On these channels, it was captioned either IBA:CH4 or IBA:S4C, with lines above and below this indicating the card was being generated by the channel, the absence of these lines meant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ETP-1
ETP-1 (or Electronic Test Pattern One) was a test card designed and used by the Independent Broadcasting Authority (IBA). After test transmissions from the IBA's Engineering Regional Operations Centre (ROC) in Croydon from 1978 it was phased in on ITV over a period starting from 1979, replacing, in different ITV regions: Test Card F, Test Card G and full screen height EBU colour bars. After ITV went 24 hours in 1988, the card ceased to be seen on the channel. It was used for both 625-line PAL and 405-line monochrome broadcasts. It was also seen extensively on both Channel 4 and S4C during both their pre-launch tests and their downtime of those channels, due to their limited hours early on. After launch, it was alternated with in-vision teletext services from ORACLE and 4-Tel on View/ Sbectel. On these channels, it was captioned either IBA:CH4 or IBA:S4C, with lines above and below this indicating the card was being generated by the channel, the absence of these lines meant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philips PM5544
The Philips PM5544 is a television pattern generator, most commonly used to provide a television station with a complex test card commonly referred to as a Philips Pattern or PTV Circle pattern. The content and layout of the pattern was designed by Danish engineer Finn Hendil ( da; 1939–2011) in the Philips TV & Test Equipment laboratory in Brøndby Municipality near Copenhagen under supervision of chief engineer Erik Helmer Nielsen in 1966–67. The equipment, the PM5544 Test Pattern Generator, which generates the pattern, was made by engineer Finn Hendil and his group in 1968–69. The same team would also develop the Spanish TVE colour test card in 1973. Since the widespread introduction of the PM5544 from the early-1970s, the Philips Pattern has become one of the most commonly used test cards, with only the SMPTE and EBU colour bars as well as the BBC's Test Card F coming close to its usage. The Philips PM5544 pattern was later incorporated into other test pattern generato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Test Card
A test card, also known as a test pattern or start-up/closedown test, is a television test signal, typically broadcast at times when the transmitter is active but no program is being broadcast (often at sign-on and sign-off). Used since the earliest TV broadcasts, test cards were originally physical cards at which a television camera was pointed, allowing for simple adjustments of picture quality. Such cards are still often used for calibration, alignment, and matching of cameras and camcorders. From the 1950s, test card images were built into monoscope tubes which freed up the use of TV cameras which would otherwise have to be rotated to continuously broadcast physical test cards during downtime hours. Electronically generated test patterns, used for calibrating or troubleshooting the downstream signal path, were introduced in the late-1960s. These are generated by test signal generators, which do not depend on the correct configuration (and presence) of a camera, and can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Test Card F
Test Card F is a test card that was created by the BBC and used on television in the United Kingdom and in countries elsewhere in the world for more than four decades. Like other test cards, it was usually shown while no programmes were being broadcast. It was the first to be transmitted in colour in the UK and the first to feature a person, and has become an iconic British image regularly subject to parody. The central image on the card shows Carole Hersee playing noughts and crosses with a clown doll, Bubbles the Clown, surrounded by various greyscales and colour test signals used to assess the quality of the transmitted picture. It was first broadcast on 2 July 1967 (the day after the first colour pictures appeared to the public on television) on BBC2. The card was developed by a BBC engineer, George Hersee (1924–2001), father of the girl in the central image. It was frequently broadcast during daytime downtime on BBC Television until 29 April 1983 and was still seen be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sine Wave
A sine wave, sinusoidal wave, or just sinusoid is a curve, mathematical curve defined in terms of the ''sine'' trigonometric function, of which it is the graph of a function, graph. It is a type of continuous wave and also a Smoothness, smooth periodic function. It occurs often in mathematics, as well as in physics, engineering, signal processing and many other fields. Formulation Its most basic form as a function of time (''t'') is: y(t) = A\sin(2 \pi f t + \varphi) = A\sin(\omega t + \varphi) where: * ''A'', ''amplitude'', the peak deviation of the function from zero. * ''f'', ''frequency, ordinary frequency'', the ''Real number, number'' of oscillations (cycles) that occur each second of time. * ''ω'' = 2''f'', ''angular frequency'', the rate of change of the function argument in units of radians per second. * \varphi, ''phase (waves), phase'', specifies (in radians) where in its cycle the oscillation is at ''t'' = 0. When \varphi is non-zero, the entire waveform appears to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integral Linearity
A measurement system consists of a sensor, to input the physical parameter that is of interest, and an output to a medium that is suitable for reading by the system that needs to know the value of the parameter. (This could be a device to convert the temperature of the surrounding air or water into the visually readable height of a column of mercury in a small tube, for example; but the conversion could also be made to an electronic encoding of the parameter, for reading by a computer system.) The integral linearity is then a measure of the fidelity of the conversion that is performed by the measuring system. It is the relation of the output to the input over a range expressed as a percentage of the full-scale measurements. Integral linearity is a measure of the device's deviation from ideal linear behaviour. The most common denotation of integral linearity is independent linearity. In the context of a digital-to-analog converter (DAC) or an analog-to-digital converter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greyscale
In digital photography, computer-generated imagery, and colorimetry, a grayscale image is one in which the value of each pixel is a single sample representing only an ''amount'' of light; that is, it carries only intensity information. Grayscale images, a kind of black-and-white or gray monochrome, are composed exclusively of shades of gray. The contrast ranges from black at the weakest intensity to white at the strongest. Grayscale images are distinct from one-bit bi-tonal black-and-white images, which, in the context of computer imaging, are images with only two colors: black and white (also called ''bilevel'' or '' binary images''). Grayscale images have many shades of gray in between. Grayscale images can be the result of measuring the intensity of light at each pixel according to a particular weighted combination of frequencies (or wavelengths), and in such cases they are monochromatic proper when only a single frequency (in practice, a narrow band of frequencies) is ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S4C Clic
S4C (, ''Sianel Pedwar Cymru'', meaning ''Channel Four Wales'') is a Welsh language free-to-air Public service broadcasting in the United Kingdom, public broadcast television channel. Launched on 1 November 1982, it was the first television channel to be aimed specifically at a Welsh-speaking audience. S4C's headquarters are based in Carmarthen, at the University of Wales Trinity Saint David's creative and digital centre, Yr Egin. It also has regional offices in Caernarfon and Cardiff. As of 2019–20, S4C had an average of 101 employees. S4C is the fourth-oldest terrestrial television channel in Wales after BBC One, ITV (TV network), ITV and BBC Two. As with Channel 4 (which launched the next day in the rest of the UK), S4C commissions all of its programmes from independent producers. BBC Cymru Wales produces programmes for S4C as part of its public service remit, including the news service ''Newyddion''. From its launch until 2010, S4C also carried English language, English-l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amplitude
The amplitude of a periodic variable is a measure of its change in a single period (such as time or spatial period). The amplitude of a non-periodic signal is its magnitude compared with a reference value. There are various definitions of amplitude (see below), which are all functions of the magnitude of the differences between the variable's extreme values. In older texts, the phase of a periodic function is sometimes called the amplitude. Definitions Peak amplitude & semi-amplitude For symmetric periodic waves, like sine waves, square waves or triangle waves ''peak amplitude'' and ''semi amplitude'' are the same. Peak amplitude In audio system measurements, telecommunications and others where the measurand is a signal that swings above and below a reference value but is not sinusoidal, peak amplitude is often used. If the reference is zero, this is the maximum absolute value of the signal; if the reference is a mean value (DC component), the peak amplitude is the maximu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathode-ray Tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms (oscilloscope), pictures (television set, computer monitor), radar targets, or other phenomena. A CRT on a television set is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT television sets and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster. In color devices, an image is produced by controlling the intensity of each of three electron beams, one for each additive primary color (red, green, and blue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cathode-ray Tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. The images may represent electrical waveforms (oscilloscope), pictures (television set, computer monitor), radar targets, or other phenomena. A CRT on a television set is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term ''cathode ray'' was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons. In CRT television sets and computer monitors, the entire front area of the tube is scanned repeatedly and systematically in a fixed pattern called a raster. In color devices, an image is produced by controlling the intensity of each of three electron beams, one for each additive primary color (red, green, and blue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
