A High Definition video format consisting of 1,080 vertical lines of display resolution in an Interlaced scan. The term usually assumes a widescreen aspect ratio of 16:9, implying a horizontal resolution of 1920 pixels and a frame resolution of 1920Ã—1080 or about 2.07 million pixels.
A type of Aspect Ratio. 16:9 is commonly known as widescreen and is wider than the standard 4:3 aspect ratio. Most new High Definition programming is in 16:9 format.
A Standard Definition video format consisting of 480 vertical lines of display resolution in an Interlaced scan. While NTSC has a total of 525 lines, only 480 of these are used to display the image for DV-NTSC.
A Standard Definition video format consisting of 480 vertical lines of display resolution in a Progressive scan, usually with a horizontal resolution of 640 pixels and 4:3 aspect ratio. The frame rate (hertz) is usually 30 or 60 progressive frames per second.
The 4:3 ratio (generally named as "Four-Three", "Four-by-Three", "Four-to-Three", or "Academy Ratio") for standard television has been in use since television's origins and many computer monitors use the same aspect ratio. 4:3 is the aspect ratio defined by the Academy of Motion Picture Arts and Sciences as a standard after the advent of optical sound-on-film. By having TV match this aspect ratio, films previously photographed on film could be satisfactorily viewed on TV in the early days of the medium (i.e. the 1940s and the 1950s). When cinema attendance dropped, Hollywood created widescreen aspect ratios (such as the 1.85:1 ratio mentioned earlier) in order to differentiate the film industry from TV.
A surround sound system that consists of front speakers (right and left), rear speakers (right and left), center channel speaker and a powered subwoofer. This is also the audio standard for digital TV and HDTV.
A Standard Definition video format consisting of 576 vertical lines of display resolution in an Interlaced scan. The format is used primarily in PAL and SECAM countries. The field rate (not to be confused with the frame rate), which is 50 Hz, is sometimes included when identifying the video mode - ie, 576i 50.
A Standard Definition video format consisting of 576 vertical lines of display resolution in a Progressive scan, usually with a horizontal resolution of 720 or 704 pixels. The frame rate can be given explicitly after the letter.
A surround sound system that consists of front speakers (right and left), front center channel speaker, rear speakers (right and left), rear center channel speaker, and a powered subwoofer.
A High Definition video format consisting of 720 vertical lines of display resolution in a Progressive scan. When broadcast at 60 frames per second, 720p features the highest temporal (motion) resolution possible under the ATSC and DVB standards. Progressive scanning reduces the need to prevent flicker by filtering out fine details, so sharpness is much closer to 1080i than the number of scan lines would suggest.
802.11ac builds upon previous 802.11 standards, particularly the 802.11n standard, to deliver data rates of 433Mbps per spatial stream, or 1.3Gbps in a three-antenna (three stream) design. The 802.11ac specification operates only in the 5 GHz frequency range and features support for wider channels (80MHz and 160MHz) and beamforming capabilities by default to help achieve its higher wireless speeds.
In signal processing and related disciplines, aliasing refers to an effect that causes different signals to become indistinguishable (or aliases of one another) when sampled. It also refers to the distortion or artifact that results when the signal reconstructed from samples is different than the original continuous signal
An Analog or analogue signal is any continuous signal for which the time varying feature (variable) of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal. It differs from a digital signal in terms of small fluctuations in the signal which are meaningful. Analog is usually thought of in an electrical context; however, mechanical, pneumatic, hydraulic, and other systems may also convey analog signals.
Attempting to capture the original sound in its entirety and then reproducing the original sound in its entirety. Analog audio has the risk of also reproducing and possibly amplifying noise or distortion. Digital audio is replacing this technology.
Display unit that only accepts analog signals. All signals in such monitors pass through a completely digital section prior to display. While many similar connectors (13W3, BNC, etc..) were used on other platforms, the IBM PC and compatible systems long ago standardised the VGA connector.
A video signal transferred by analog signal. It contains the luminance (brightness) and chrominance (colour) of the image, which may be carried in separate channels, as in component video (YPbPr) and S-Video, or combined in one channel, as in composite video and RF connector.
The process that horizontally squeezes a widescreen (16:9) image so that it can be stored into a standard 4:3 aspect ratio DVD image frame. When played back on a 4:3 television, the DVD player usually restores the correct aspect ratio and generates black bars at the top and bottom of the frame. If the DVD player is set up incorrectly, the picture may be distorted, making objects appear thin and tall. If content is viewed on a 16:9 display, the TV restores the anamorphic widescreen image to its original proportions. Non-anamorphic video played on the same television has not only the black bars at the top and bottom, but grey bars on the left and right because the video signal is more square than the television screen.
An antenna (or aerial) is a transducer designed to transmit or receive electromagnetic waves. In other words, antennas convert electromagnetic waves into electrical currents and vice versa. They are used with waves in the radio part of the electromagnetic spectrum, that is, radio waves, and are a necessary part of all radio equipment. Antennas are used in systems such as radio and television broadcasting, point-to-point radio communication, wireless LAN, cell phones, radar, and spacecraft communication. Antennas are most commonly employed in air or outer space, but can also be operated under water or even through soil and rock at certain frequencies for short distances.
Antialiasing is a procedure which, by smoothing and filtering, eliminates or reduces the distortion artifacts known as aliasing when representing a high-resolution signal at a lower resolution. The procedure usually involves low pass filtering of the processed signal prior to digitising in order to eliminate signals, having frequencies close to and greater than half of the sampling frequency.
The ratio between the width and height of the TV picture on the screen. There are two common TV screen shapes that most people will recognise - for television monitors it is either 4:3 ('standard') or 16:9 ('widescreen'). NTSC analog TV systems use a 4:3 aspect ratio, while ATSC uses the wider 16:9 aspect ratio. While most new HD programming is in 16:9, a significant amount of TV broadcasts are still sent in the conventional 4:3 ratio. When watching 4:3 programs on a HDTV 'pillar boxing' may occur, with black columns displayed on the left and right of the image.
The range of audio frequencies over which an amplifier or receiver will respond and provide useful output. The highest practical frequency which the human ear can normally hear is 20 kHz. An audio amplifier which processes all frequencies equally (flat response from 20 Hz to 20 kHz) and a reasonably high signal-to-noise ratio, will faithfully reproduce the full range of perceptible sound.
A receiver, amplifier, audio and video switcher in one unit encompassing sound decoding with processing allowing for surround sound and multi-channel distribution.
AVI (Audio Video Interleaved) is a computer video/graphics format. AVI files can contain both audio and video data in a file container that allows synchronous audio-with-video playback
American Wire Gauge is a standardised wire gauge system used to measure wire or cable thickness. Speaker cable is often measured this way. The gauge number gets smaller as the thickness of the wire increases, eg very fine wire (for example 30 gauge) is much smaller than 4 gauge wire. The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity
Primarily a video only signal, transmitting raw video without frequency shifting, multiplexing, or frequency modulation. Imagine the video signal being pushed down the coaxial cable line at a very low frequency (5 MHz). Baseband signaling is used for CCTV (Closed Circuit Television) and for some home automation products.
A video signal comprising sync and colour burst signals which generate a black image on the screen. It is used to synchronise (Genlock) other video sources to the same sync and colour information. This is important during video editing situations where all video decks and cameras need their video clocks to be synchronised.
Blu-ray Disc (also known as Blu-ray or BD) is an optical disk storage media format designed to supersede the standard DVD format. The name Blu-ray Disc is derived from the blue-violet laser used to read and write this type of disc. Its main uses are for storing high-definition video, PlayStation 3 video games, and other data, with up to 25 GB per single layered, and 50 GB per dual layered disc. Although these numbers represent the standard storage for Blu-Ray drives, the specification is open-ended, with the upper theoretical storage limit left unclear. The disc has the same physical dimensions as standard DVDs and CDs.
Blue key generation is a process where a subject is filmed or photographed against a background consisting of a single colour - Blue. The portions of the video which match the blue background are replaced by the alternate background video. This process is commonly known as "keying", "keying out" or simply a "key". The Blue Key process is often referred to simply as 'Bluescreen'. Blue is often used as it is the complementary colour to flesh tone - since the most common colour in most scenes is flesh tone, the opposite colour is the logical choice to avoid conflicts.
Bluetooth is an open wireless protocol for transfer of data over a short distance (using short length radio waves). It was originally conceived as a wireless alternative to RS-232 data cables. Because the devices use a radio (broadcast) communications system, they do not have to be in line of sight of each other. It can connect several devices, overcoming problems of synchronisation.
Broadband over power line (BPL) is a broadband power line access technology that deploys the electricity grid to run broadband applications. It is a low-cost, scalable, secure system that integrates broadband, radio, Ethernet, networking, and HomePlug technologies to deliver high-speed data over existing power lines. The BPL Access solution works in even the hardest-to-reach building environments, and can use any type of Internet signal, including DSL, T1, E1, cable and satellite.
A video and audio signal multiplexed/frequency shifted to a higher frequency in the 54 MHz to 890 MHz range for cable TV and up to 2.2 GHz for the mini dish satellite. This is the common method for video transmission by cable TV and DSS satellite.
A TV system that uses fixed optical fibers or coaxial cables as opposed to the over-the-air method used in traditional television broadcasting (via radio waves) in which a television antenna is required. Hundreds of channels can be transmitted simultaneously with CATV, which is almost impossible with traditional television broadcasting.
A capacitive touchscreen panel consists of an insulator such as glass, coated with a transparent conductor such as indium tin oxide (ITO). As the human body is also a conductor, touching the surface of the screen results in a distortion of the body's electrostatic field, measurable as a change in capacitance. The location is then sent to the controller for processing. Capacitive touchscreens are mainly used with human touch input. A standard stylus cannot be used for capacitive sensing, unless it is tipped with some form of conductive material, such as anti-static conductive foam.
Category 5 cable, commonly known as Cat 5 or Cat-5, is an unshielded twisted pair type cable designed for high signal integrity. Used mostly for communication and networking systems - most commonly known as being rated for its Ethernet capability of 100 Mbit/s. Cat 5 cable typically has three twists per inch of each twisted pair of 24 gauge (AWG) copper wires within the cables.
Category 5e cable is an enhanced version of Category 5 that adheres to more stringent standards. It is capable of transmitting data at speeds of up to 1000 Mbps (1 Gigabit per second).
Category 6 cable, commonly referred to as Cat 6 or Cat-6, is a cable standard designed to perform at frequencies of up to 250 MHz and offers higher performance for better transmission of data at speeds up to 1000 Mbps. Backwards compatible with the Category 5/5e and Category 3 cable standards. Cat 6 features more stringent specifications for crosstalk and system noise.
A cold cathode is an element used within some nixie tubes, gas discharge lamps, discharge tubes, and vacuum tubes. The term cold cathode refers to the fact that the cathode is not independently heated. In spite of this, the cathode itself may still operate at temperatures as high as if the cathode were heated. Cold cathode fluorescent lamps (CCFLs) are usually also called cold cathodes. Neon lamps are a very common example of a cold cathode lamp. Cold cathodes remain popular for LCD backlighting and enthusiast computer case modders.
Closed Circuit Television, a platform used for security cameras and monitors, which operates on baseband signal. CCTV is very popularin the security community.
Color Graphics Adapter. CGA was IBM's first colour graphics card and the first colour computer display standard for the IBM PC.The highest resolution of any mode was 640Ã—200 pixels, and the highest colour depth supported was 4-bit (16 colours). The CGA card was succeeded in the consumer space by IBM's Enhanced Graphics Adapter (EGA) card, which supports most of CGA's modes and adds an additional resolution (640Ã—350) as well as a software-selectable palette of 16 colours out of 64 in both text and graphics modes.
A chipset or chip set refers to a group of integrated circuits, or chips, that are designed to work together. Manufacturers of VGA cards, computer main boards, multimedia hardware and other video hardware use chip-sets to perform specific tasks which are integrated into the work of the entire board.
The technique for mixing two images or frames together in which a colour (or a small colour range) from one image is removed (or made transparent), revealing another image behind it. For example it is commonly used for weather forecast broadcasts, where the presenter appears to be standing in front of a large map, but in the studio it is actually a large blue or green background. A Blue or Green background is usually favoured as these colours are considered to be the furthest away from skin tone.The Chroma Key process is based on the luminance key. In a luminance key, everything in the image over (or under) a set brightness level is "keyed" out and replaced by either another image, or a colour from a colour generator. See Blue Key.
Chrominance is the colour portion of a video signal. Often abbreviated to Chroma. Chrominance is separate to the other colour portion of a video signal - luminance (brightness). Chrominance tells the video display what colours to use and how much saturation (amount of pure colour) to use, while luminance gives the colours depth and contrast by adjusting the darkness and brightness of the image.
Coaxial cable (or 'coax') is a shielded copper wire cable which consists of two conductors that share a common axis. The inner conductor is typically a straight wire, either solid or stranded, and the outer conductor is typically a shield that might be braided or woven. Coaxial cable is used as a transmission line for radio frequency signals, in applications such as connecting radio transmitters and receivers with their antennas, computer network (Internet) connections, and distributing cable television signals. The RF industry uses standard type-names for coaxial cables. Thanks to television, RG-6 is the most commonly-used coaxial cable for home use.
This term is short for "Coder-decoder." A codec is a program used for encoding and decoding a digital signal, usually employing compression/decompression algorithms to streamline the data and conserve bandwidth.
A symptom of insufficient colour depth, colour banding occurs when a monitor is unable to render smooth colour gradients, and instead presents stripes or bands of colour, especially in very light or very dark areas of an image. While in 24 bit colour modes, 8 bits per channel should be enough to render images in the full visible spectrum, in some cases there is a risk of producing abrupt changes between shades of the same colour. For instance, displaying natural gradients (like sunsets, dawns or clear blue skies) can show minor banding.
Colour depth (also known as bit depth), is a term describing the number of bits used to represent the colour of a single pixel. Greater colour depth gives a larger number of distinct colours, i.e. millions or billions of colours, allowing for smoother colour gradients. This concept is also known as bits per pixel (bpp), particularly when specified along with the number of bits used. See also Deep Colour
In signal processing, a comb filter adds a delayed version of a signal to itself, causing constructive and destructive interference. Comb filtering is a digital process designed for the separation of Y and C from a composite video signal, based on 'combing' out the chrominance signal from the luminance. The frequency response of a comb filter consists of a series of regularly-spaced spikes, giving the appearance of a comb.
Component video is a video signal that has been split into two or more components. When used without any other qualifications the term component video generally refers to analog YPbPr component video with sync on luma. Unlike Composite Video where all the video information is combined into a single line-level signal, Component Video is transmitted or stored as three separate signals. Component Video cables do not carry audio.
Composite Video is a video colour format where the video information is combined into a single channel. It is a composite of three source signals called Y, U and V (together referred to as YUV) with sync pulses. Y represents the brightness or luminance of the picture and includes synchronising pulses, so that by itself it could be displayed as a monochrome picture. U and V represent hue and saturation or chrominance; between them they carry the colour information. In typical home applications, the composite video signal is usually connected using an RCA Plug (usually represented by a yellow coloured plug, and often accompanied with red and white for right and left audio channels respectively).A BNC connector and higher quality coaxial cables are often used in more professional applications.
The Cathode Ray Tube (CRT) is a vacuum tube which produces light when an electron beam hits its internal surface. An electron gun creates the electrons, and a high voltage source that accelerates them generates the electron beam.The CRT is used as a picture displaying tube in video monitors, TV sets, computer monitors and others. The CRT uses an evacuated glass envelope which is large, deep, heavy, and relatively fragile. Display technologies without these disadvantages such as flat plasma displays, LCD, DLP, and OLED have replaced CRTs in many applications and are becoming increasingly common as costs decline.
Digital to Analog Converter. A device doing the opposite of an ADC (Analog to Digital Converter), converting a digital logic signal to an analog (linear) signal. The ADC and DAC are widely used for conversion between analog and digital video and audio signals.
In computer science, data is anything in a form suitable for use with a computer. Data is often distinguished from programs. A program is a set of instructions that detail a task for the computer to perform. In this sense, data is thus everything that is not program code.
DC (Direct Current) is the unidirectional flow of electric charge. Direct current is produced by such sources as batteries, thermocouples, solar cells, and commutator-type electric machines of the dynamo type. Direct current may flow in a conductor such as a wire, but can also be through semiconductors, insulators, or even through a vacuum as in electron or ion beams. The electric charge flows in a constant direction, distinguishing it from alternating current (AC).
The Display Data Channel or DDC is a collection of digital communication protocols between a computer display and a graphics adapter. Using DDC, a monitor can inform the adapter/video card about its properties, such as maximum resolution and colour depth.The DDC suite of standards was created by the Video Electronics Standards Association (VESA), and aims to provide a "plug and play" experience for computer displays.
A Device Driver Interface or software driver is a computer program allowing higher-level computer programs to interact with a hardware device.A driver typically communicates with the device through the computer bus or communications subsystem to which the hardware connects. When a calling program invokes a routine in the driver, the driver issues commands to the device. Once the device sends data back to the driver, the driver may invoke routines in the original calling program. Drivers are hardware-dependent and operating-system-specific. They usually provide the interrupt handling required for any necessary asynchronous time-dependent hardware interface.
Accepted unit of measure to express amplitude or power difference. A common measure for sound and also used often in measuring effectiveness of amplifiers.
A term used to describe a colour gamut comprising a billion or more colours. The HDMI 1.3 specification supports Deep Colour bit depths. It defines bit depths for Deep Colour as 30 bits (1.073 billion colours), 36 bits (68.71 billion colours), and 48 bits (281.5 trillion colours).
Deinterlacing is the process of converting interlaced video, such as common analog television signals or 1080i format HDTV signals, into a non-interlaced form (progressive).With interlaced video, since each field is only half the scanlines of a full frame, interpolation must be used to form the missing scanlines. There are various methods of doing the interpolation, ranging from simply doubling scanlines to motion-adaptive methods. Ideally, each field becomes its own frame of video, so an interlaced NTSC clip at 29.97 frames per second stream becomes a 59.94 frame per second progressive.
A non-conductive material used to insulate around a cable conductor that helps to retain charge.
Differential gain is the error in the amplitude of the colour signal due to a change in luminance (brightness) level. It is measured by comparing two chrominance signals of initially equal amplitudes riding on two different luminance levels. The inaccuracy is measured as a percentage. Differential gain is important to video signals because if the amplitude of the subcarrier signal changes with a change in luminance level, then the picture being displayed will have colour saturation problems.
Differential phase is the error in the phase of the colour signal due to a change in luminance (brightness) level. It is measured by comparing two chrominance signals of initially equal phases riding on two different luminance levels. The inaccuracy is measured in degrees. The phase of the colour signal is responsible for displaying the proper hue, or base colour. Differential phase is important to video signals because if the phase of the subcarrier signal changes with a change in luminance level, then the picture being displayed will have colour selection problems.
The recreation of sound by high-speed digital sampling. Analog signals are converted to a chain of 0â€™s and 1â€™s allowing for sophisticated decoding and encoding and electronic manipulation. The risk of reproducing and possibly amplifying noise or distortion is minimized.
Allows for Digital Audio multiple channels to be transmitted through one cable. This cable is the purest quality transmission of Digital Audio Signal.
Sends a Digital Audio multiple channels by using a light transmission and therefore is virtually noise and distortion resistant.
The recreation of video by high speed digital sampling. Analog signals are converted to a chain of 0â€™s and 1â€™s allowing for sophisticated decoding and encoding and electronic manipulation. The risk of reproducing and possibly amplifying noise or distortion is minimized.
A device used to combine an amplified antenna and satellite signals, which operate at different frequencies, into a signal, which can travel through one cable. An amplified diplexer is used at the antenna and satellite dish location only when the antenna is amplified. A non-amplified diplexer is always used at the satellite receiver location to separate signals and distribute to TVs.
A device used to combine antenna and satellite signals, which operate at different frequencies, into a signal, which can travel through one cable. A non-amplified diplexer is used at the antenna and satellite dish location when the antenna is not amplified. A non-amplified diplexer is always used at the satellite receiver location to separate signals and distribute to TVs.
A digital display interface standard introduced by the Video Electronics Standards Association (VESA). It defines a new royalty-free, digital audio/video interconnect, intended to be used primarily between a computer and its display monitor, or a computer and a home-theater system. Display Port is a competitor to the HDMI connector, the current standard digital connection for high-definition consumer electronics devices.
A distribution amplifier is a device that accepts a single input signal and provides this same signal to multiple isolated outputs. A good quality distribution amplifier amplifies and pre-compensates the incoming signal to avoid signal degradation, before generating multiple identical buffered and amplified outputs.
Digital Light ProcessingÂ® is a proprietary Texas Instruments technology that uses micro-mirrors on a chip to switch light for video projection, including digital televisions. DLP is used in DLP front projectors (small standalone projection units) and DLP rear projection displays. DLP is the current market-share leader in professional digital movie projection, largely because of its high contrast ratio and available resolution as compared to other digital front-projection technologies. DLP technology has also gained market share in the front projection market, with over 30 manufacturers using the DLP chipset to power their projectors.
Dolby Surround was the earliest consumer version of Dolby's multi channel analog film sound decoding format Dolby Stereo, introduced to the public in 1982. The system has four channels of audio information - left, centre, right, and mono surround â€“ which are matrix-encoded onto two audio tracks. The stereo information is then carried on stereo sources such as videotapes, laserdiscs and television broadcasts from which the surround information can be decoded by a processor to recreate the original four-channel surround sound.
A family of multi-channel audio codecs/audio compression technologies from Dolby Laboratories, based on AC-3 technology. Dolby Digital includes several similar technologies, such as Dolby Digital EX, Dolby Digital Live, and Dolby Digital Plus. The most common of these is simply called 'Dolby Digital' which contains up to six discrete channels of sound. The most elaborate mode in common usage involves five channels for normal-range speakers (20 Hz â€“ 20,000 Hz) (right front, centre, left front, right rear and left rear) and one channel (20 Hz â€“ 120 Hz allotted audio) for the subwoofer driven low-frequency effects.
An advanced lossless multi-channel audio codec developed by Dolby Laboratories which is intended primarily for high-definition home-entertainment equipment such as Blu-ray Disc and HD DVD. Dolby TrueHD is a lossless audio format, meaning that no audio information is lost when the signal is compressed and uncompressed. It supports up to eight full-range channels of 24-bit/96 kHz audio. Dolby TrueHD competes with DTS-HD Master Audio, a similar lossless codec from Digital Theater Systems sound. It is the successor to the AC-3 Dolby Digital surround sound codec which was used as the audio standard for DVD discs.
Dolby TrueHD is an advanced lossless multi-channel audio codec developed by Dolby Laboratories which is intended primarily for high-definition home-entertainment equipment such as Blu-ray Disc and HD DVD. Dolby TrueHD is the successor to the AC-3 Dolby Digital surround sound codec which was used as the audio standard for DVD discs. In this application, Dolby TrueHD competes with DTS-HD Master Audio, another lossless codec from Digital Theater System.
The standard for Home Theater Surround Sound Systems, included in most audio/video receivers. The Pro LogicÂ® decoder directs the movement of sound between speakers.
A digital sound format, which is the basis of surround sound systems. May be 5.1, which is front speakers (right and left), rear speakers (right and left), center channel speaker, and a powered subwoofer. May be a 6.1, which is front speakers (right and left), front center channel speaker, rear speakers (right and left), rear center channel speaker, and a powered subwoofer.
An "always on" high speed internet connection using existing (on premises) copper telephone lines transmitting signals at a much higher speed than analog (voice). Data and voice are shared over the same copper lines simultaneously without interference.
DSL Filter â€“ A device used with DSL that allows the data and voice to travel over the same line simultaneously without interference, and also filters out impedance from telephone equipment. Usually required for each telephone device.
A digital satellite infrastructure used to beam signals to home systems equipped with a mini dish and satellite receivers, with in excess of 200 channels being received.
DTS (Digital Theater Systems) is a company specialising in multichannel digital surround sound formats used for both commercial/theatrical and consumer grade applications. The term DTS usually refers to the multi-channel audio codecs from the company, including DTS, DTS-ES, DTS Neo:6, and DTS 96/24. DTS audio codecs are used in both commercial and home theatre applications. The basic and most common version of the format is a 5.1-channel system, which encodes the audio as five primary (full-range) channels plus a special LFE (low-frequency effect) channel for the subwoofer. However encoders and decoders can support numerous channel combinations.
The second of two DTS High Definition audio formats. It supports a virtually unlimited number of surround sound channels, can downmix to 5.1 and two-channel, and can deliver audio quality at bit rates up to lossless (24-bit, 192 kHz). DTS-HD Master Audio is selected as an optional surround sound format for Blu-ray and HD-DVD, where it has been limited to a maximum of 8 discrete channels.
Digital television (DTV) is the sending and receiving of moving images and sound by discrete (digital) signals, in contrast to the analog signals used by analog TV. Digital television supports many different picture formats defined by the combination of size, aspect ratio and interlacing. There are a number of different ways to receive digital television. One of the oldest means of receiving DTV is using an antenna/aerial. This way is known as Digital Terrestrial Television (DTT). With DTT, viewers are limited to whatever channels the antenna picks up. Signal quality will also vary. Other ways have been devised to receive digital television, including digital cable and digital satellite. Digital television broadcast standards include the DVB family used throughout Europe including DVB-S (satellite), DVB-T (terrestrial), and DVB-C (cable); the ATSC family used throughout North America including ATSC (terrestrial/cable) and ATSC-M/H (mobile/handheld); and the ISDB family used throughout Japan and South America including ISDB-S (satellite), ISDB-T (terrestrial) and ISDB-C (cable).
Dual Play mode enables two people to play on the same screen and is presumably compatible with any console game that includes a top-bottom split screen. With Dual Play enabled and the special Dual Play glasses, the company says players see two discreet, full-screen images, as opposed to the traditional split screen.
Digital Video Broadcasting (DVB) is a suite of internationally accepted open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium with more than 270 members, and they are published by a Joint Technical Committee (JTC) of European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). The interaction of the DVB sub-standards is described in the DVB Cookbook. Many aspects of DVB are patented, including elements of the MPEG video coding and audio coding.
DVD (Digital Versatile Disc) is an optical disc storage media format. Its main uses are video and data storage. DVDs are of the same dimensions as compact discs (CDs), but store more than six times as much data. Variations of the term DVD often indicate the way data is stored on the discs: DVD-ROM (read only memory) has data that can only be read and not written; DVD-R and DVD+R (recordable) can record data only once, and then function as a DVD-ROM; DVD-RW (re-writable), DVD+RW, and DVD-RAM (random access memory) can all record and erase data multiple times.
A DRM (Digital Rights Management) technique designed to allow motion picture studios to control aspects of a release, including content, release date, and price, according to the region. DVD video discs may be encoded with a region code restricting the area of the world in which they can be played. The commercial DVD player specification requires that a player to be sold in a given place not play discs encoded for a different region, however region-free DVD players are also commercially available.
Digital Visual Interface (DVI) is a is a video interface standard designed to provide very high visual quality on digital display devices such as flat panel LCD computer displays and digital projectors. It was developed by an industry consortium to replace the "legacy analog technology" VGA connector standard. It is designed for carrying uncompressed digital video data to a display. It is partially compatible with the High-Definition Multimedia Interface (HDMI) standard in digital mode (DVI-D), and VGA in analog mode (DVI-A). A DVI-I connector transfers digital and analog VGA type signals on additional pins.
Use for connecting HDTVs, digital flat-panel displays and other video components with DVI connections to digital DVD player, or other equipment with DVI connections.
Uses large capacity hard drive and internal processing to increase recording time of television shows compared to regular VCRs. Also, has technology to program and control live broadcast.
The Extended Display Identification Data (EDID) is a data-structure, provided by a display monitor, to describe its capabilities to a graphics card connected to it. It is what enables a modern personal computer to know what kind of monitor is connected. The EDID includes the manufacturer's name, the product type, the timing data supported by the display, the display size, luminance data and (for digital displays only) pixel mapping and other data.
Enhanced Definition Television, also known as Extended Definition Television. EDTV is a format that delivers a picture that is superior to that of standard definition television (SDTV), but not as detailed as high definition television (HDTV). For example a television may accept a HDTV signal, will only display at a resolution of up to 480P.
The IBM PC computer display standard specification located between CGA and VGA in terms of colour and space resolution. EGA (Enhanced Graphics Adapter) produces a display of 16 simultaneous colours from a palette of 64 at a resolution of up to 640Ã—350 pixels. The EGA standard was made obsolete by the introduction of VGA and later higher resolutions.
Equalization, or EQ for short, means boosting or reducing (attenuating) the levels of different frequencies in a signal. The term generally implies Amplitude equalization, but any frequency dependent response characteristic could be equalized. Audio equalization for example breaks down the audio spectrum into several frequency bands to compensate for changes in audio frequency-dependent levels, allowing the user to control (boost or cut) each frequency segment individually.
Extended Video Graphics Array (or EVGA) is a standard created by VESA in 1991 denoting a non-interlaced resolution of 1024x768 at a maximum of 70Hz refresh rate. EVGA is similar to (but is not the same as) the IBM XGA standard.
Federal Communications Commission. The U.S telecommunications regulator, an Independent agency of the American Government which regulates all non-federal government use of the radio spectrum (including radio and television broadcasting), all interstate telecommunications (wire, satellite and cable), as well as all international communications that originate or terminate in the United States.
Refers to the medium and the technology associated with the transmission of information as light pulses along a glass or plastic wire or fiber. Optical fiber carries much more information than conventional copper wire and is in general not subject to electromagnetic interference and the need to retransmit signals. The signal loss in a fiber optics system is usually smaller than in coaxial cables, and so optic fibers are often used to carry signals over extremely long distances.
A IEEE 1394 digital interface cable, that is a very high speed, bi-directional serial cable that can be used with digital devices such as camcorders, computers, hard disks, and audio and video editing equipment. A newer technology and only some electronic equipment provides for this technology.
Display technologies such as LCD, Plasma and DLP that use an non-fluctuating matrix of pixels with a set number of pixels in each row and column. These display devices have actual pixels (picture elements) that make up the display. With such displays, adjusting (scaling) to different aspect ratios because of different input signals requires complex processing. In contrast, the CRT electronics architecture "paints" the screen with the required number of pixels horizontally and vertically.
Free Lossless Audio Codec (FLAC) is an audio codec audio data compression. FLAC accomplishes data compression without sacrificing the integrity of the audio source, since it does not discard any part of the data. A digital audio recording (such as a CD track) converted by FLAC can be decompressed into an identical copy of the audio data. Audio sources encoded to FLAC are typically reduced to 50â€“60% of their original size.
A television that usually has gas plasma or LCD (Liquid Crystal Display) technology and is only a few inches thick.
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency. The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency. When a low frequency signal modulates (changes) the frequency of an RF signal of a much higher frequency (causing it to move around the basic carrier frequency) - the process is called frequency modulation or FM. This system is extensively used in broadcast radio transmission, as it retains high signal quality.
When a low frequency signal modulates (changes) the frequency of an RF signal of a much higher frequency (causing it to move around the basic carrier frequency) - the process is called frequency modulation or FM. This system is extensively used in broadcast radio transmission, as it retains high signal quality.
A High Definition video format consisting of 1,080 vertical lines of display resolution in a Progressive scan, meaning the image is not interlaced. Only 1080p can be referred to as full HD or full high definition although 1080i (interlaced) is also 1920x1080 pixels.
A technique where the video output of one source is used to synchronise other video sources together. The aim in video and digital audio applications is to ensure the coincidence of signals in time at a combining or mixing or switching point. When sources are synchronised in this way, they are said to be genlocked. Genlock can be used to synchronise as few as two isolated sources (e.g. a television camera and a videotape machine feeding a vision mixer, also known as a production switcher in North America), or in a wider facility where all the video sources are locked to a single synchronising pulse generator (e.g. a fast paced sporting event featuring multiple cameras and recording devices).
A video interference phenomenon where the video image may appear double and the second image will be faint, thus the term "ghost".
High Efficiency Video Coding (HEVC) is a video compression format, a successor to H.264/MPEG-4 AVC (Advanced Video Coding), that was jointly developed by the ISO/IEC Moving Picture Experts Group (MPEG) and ITU-T Video Coding Experts Group (VCEG) as ISO/IEC 23008-2 MPEG-H Part 2 and ITU-T H.265.MPEG and VCEG established a Joint Collaborative Team on Video Coding (JCT-VC) to develop the HEVC standard.HEVC is said to double the data compression ratio compared to H.264/MPEG-4 AVC at the same level of video quality. It can alternatively be used to provide substantially improved quality at the same bit rate. It can support 8K UHD and resolutions up to 8192×4320.The first version of the standard was completed and published in early 2013. Several extensions to the technology remain under active development, including range extensions (supporting enhanced video formats), scalable coding extensions, and 3D video extensions.
High Definition (HD) Generally refers to any video system of higher resolution than standard-definition (SD) video, and most commonly involves display resolutions of 1280Ã—720 pixels (720p) or 1920Ã—1080 pixels (1080i/1080p).
Indicates the capability of a television to display High Definition video content. HD Ready refers to any display that is capable of accepting and displaying a high definition signal at either 720p, 1080i or 1080p using a component video or digital input, and does not have a built-in HD-capable tuner. The HD Ready label was introduced as a way to differentiate display equipment to help consumers, as previously many TV sources and displays were being promoted as capable of high definition when they were not.
High-definition DVD is a now defunct high-density optical disc format for storing data and high-definition video. HD-DVD was one of two potential successor technologies to the DVD. Supported principally by Toshiba, in February 2008 the company abandoned the format, announcing it would no longer develop or manufacture HD-DVD players or drives. Rival format Blu-Ray Disc is now seen as the current standard optical disc format to store large amounts of data and high definition video.
High-bandwidth Digital Content Protection (HDCP) is a form of digital copy protection to prevent the copying of digital audio and video content as it travels across connections (mainly DVI and HDMI). The specification is proprietary, and implementing HDCP requires a license. One of the key terms of HDCP states that high-definition digital video sources must not transmit protected content to non-HDCP-compliant receivers. This sometimes causes handshaking problems, especially with older high-definition displays.
HDMI (High-Definition Multimedia Interface) is a compact audio/video interface for transmitting uncompressed digital data, and represents a digital alternative to consumer analog standards. HDMI provides an interface between any compatible digital audio/video source (such as a set-top box, DVD player, games console etc) and a compatible digital audio and/or video monitor. HDMI supports, on a single cable, any TV or PC video format including standard, enhanced, and high-definition video, along with up to 8 channels of digital audio and a Consumer Electronics Control (CEC) connection. Because HDMI is electrically compatible with the signals used by Digital Visual Interface (DVI), no signal conversion is necessary, nor is there a loss of video quality when a DVI-to-HDMI adapter is used.
Use for connecting HDTVs, digital flat-panel displays and other video components with HDMI connections to digital DVD player, Digital A/V receiver or other equipment with HDMI connections. This provides the best detail, truest color and sound, and highest resolution.
HDMI 1.0 was released December 9, 2002 and is a single-cable digital audio/video connector interface with a maximum TMDS bandwidth of 4.9 Gbit/s. It supports up to 3.96 Gbit/s of video bandwidth (1080p/60 Hz or UXGA) and 8 channel LPCM/192 kHz/24-bit audio. HDMI 1.1 was released on May 20, 2004 and added support for DVD-Audio. HDMI 1.2 was released August 8, 2005 and added support for One Bit Audio, used on Super Audio CDs, at up to 8 channels.
HDMI 1.3 was released June 22, 2006 and increased the single-link bandwidth to 340 MHz (10.2 Gbit/s). It optionally supports Deep Color, with 30-bit, 36-bit, and 48-bit xvYCC, sRGB, or YCbCr, compared to 24-bit sRGB or YCbCr in previous HDMI versions. It also optionally supports output of Dolby TrueHD and DTS-HD Master Audio streams for external decoding by AV receivers.
HDMI 1.4 was released on May 28, 2009 and increases the maximum resolution to 4K Ã— 2K (3840Ã—2160p at 24Hz/25Hz/30Hz and 4096Ã—2160p at 24Hz, which is a resolution used with digital theatres). Also introduced is the HDMI Ethernet Channel, which allows for a 100 Mb/s Ethernet connection between the two HDMI connected devices, as well as a new Micro HDMI Connector and expanded support for colour spaces.
HDMI 2.0 is an improved standard for AV connectivity and the heir apparent to HDMI 1.4 (released back in 2009). You'll need an HDMI 2.0-compatible HD TV if you're interested in watching the full range of 4K Ultra HD source material in the future.
High Definition TV is Full HD or HD ready.
Converts video signal (either analog cable, digital cable or HDTV) for display on a television. HDTV- Ready (without built-in HDTV tuner) televisions must be connected to a compatible HDTV tuner set-top box to receive digital television programs.
A television that has the technology to display either high definition formats (720p, 1080i) but does not have the required tuner/converter box to receive digital signals.
HDV is a format for recording of high-definition video on DV cassette tape. The format was originally developed by JVC and supported by Sony, Canon and Sharp. The four companies formed the HDV consortium in September 2003. Conceived as an affordable high definition format for digital camcorders, HDV quickly caught on with many amateur and professional videographers due to its low cost, portability and image quality acceptable for many professional productions. Two major versions of HDV are HDV 720p and HDV 1080i. The former is used by JVC and is informally known as HDV1. The latter is preferred by Sony and Canon and is sometimes referred to as HDV2. The HDV 1080i defines optional progressive recording modes, and in recent publications is sometimes called HDV 1080 or 1080-line HDV as progressive 1080-line recording becomes commonplace. HDV is related to XDCAM family of recording formats, which uses the same encoding scheme. 1080-line HDV is equivalent to 25 Mbit/s recording mode of XDCAM.
One cycle per second, kilohertz equals 1000 cycles per second, the accepted measure of frequency.
A video format consisting of either 720 active lines of progressive video or 1080 active lines of either progressive or interlaced video. Offers the highest-resolution format.
HomePlug AV (HPAV) represents the next generation of technology from the HomePlug Powerline Alliance. Its purpose is to provide high-quality, multi-stream, entertainment oriented networking over existing AC wiring within the home, while addressing interoperability with HomePlug 1.0. HPAV employs advanced PHY and MAC technologies that provide a 200 Mbps (million bits per second) class powerline network for video, audio and data. The Physical (PHY) Layer utilizes this 200 Mbps channel rate to provide a 150 Mbps information rate with robust, near-capacity communications over noisy power line channels.
In 2010, the HomePlug Green PHY specification was released to drive emerging smart energy, home automation & control and electric vehicle communication applications. HomePlug Green PHY technology brings a completely new dimension to networking via the powerlines; products based on HomePlug GP are expected to have up to 75% lower cost and 75% less power consumption than HomePlug AV. HomePlug GP can be embedded in Smart Home devices such as smart appliances and programmable communicating thermostats (PCTs), electric meters and plug-in electric vehicles (PEVs) – all applications where low cost is a more important consideration than high data throughput. It can be used in smart energy applications such as demand response, load control, energy efficiency, as well as for home/building automation. HomePlug GP technology has obvious advantages versus older, low-speed PLC technologies. Because GP operates at much higher frequencies, it is much more impervious to noise on the powerline, and GP has no difficulties with phase coupling. Also, as mentioned above, since HomePlug GP is interoperable with HomePlug AV and AV2 and supports both IPv4 and IPv6, it enables a true merging of home automation and home control with high speed digital entertainment home networks. This will make it easy to create apps where energy management and home automation are viewed and controlled via a smart TV or smart phone.
HSXGA, an abbreviation for Hex[adecatuple] Super Extended Graphics Array, is a display standard that can support a resolution of roughly 5120Ã—4096 pixels with a 5:4 aspect ratio. The name comes from the fact that it has sixteen (hexadecatuple) times as many pixels as an SXGA display.
Hue determines the weakness or intensity of a colour. If a particular colour is added to any other type of colour, the intensity of every colour created should be very nearly the same. In the NTSC standard, hue errors are more common than in the PAL standard due to a different colour encoding system. The PAL system compensates for colour problems and it corrects wrong hues during operation.
HUXGA, an abbreviation for Hex[adecatuple] Ultra Extended Graphics Array, is a display standard that can support a resolution of roughly 6400Ã—4800 pixels with a 4:3 aspect ratio. The name comes from the fact that it has sixteen (hexadecatuple) times as many pixels as an UXGA display.
HXGA an abbreviation for Hex[adecatuple] Extended Graphics Array is a display standard that can support a resolution of 4096Ã—3072 pixels (or 3200 pixels) with a 4:3 aspect ratio. The name comes from the fact that it has sixteen (hexadecatuple) times as many pixels as an XGA display. This is the highest experimental and non-widescreen resolution, and there are no devices that can render images at such high resolution, but several digital cameras can record such images. The wide screen display size is WHXGA.
IEEE-1394 is a high speed serial digital interfacing standard used to transfer digital video signals from one piece of equipment to another. The technology was developed by Apple and is also known as FireWire or iLink. It can transmit at data rates of up to 400Mb/s, more than enough to handle MPEG1 or MPEG2 compressed digital bitstreams, and sufficient for some uncompressed digital video formats. Updated versions allow a transfer rate of close to 800Mb/s. A typical IEEE-1394 interface cable may have two shielded TWP cables for bidirectional information transfer, plus two optional additional wires for supply of DC power. This type of cable can convey digital video bitstreams over distances up to about 4.5m.
Measured in ohms, the amount of resistance to the flow of current.
An infrared touchscreen uses an array of X-Y infrared LED and photodetector pairs around the edges of the screen to detect a disruption in the pattern of LED beams. A major benefit of such a system is that it can detect essentially any input including a finger, gloved finger, stylus or pen. It is generally used in outdoor applications and point-of-sale systems which cannot rely on a conductor (such as a bare finger) to activate the touchscreen. Unlike capacitive touchscreens, infrared touchscreens do not require any patterning on the glass which increases durability and optical clarity of the overall system.
Picture display process that shows every odd line at one scan of the screen and then shows all the even lines on the second scan. Since there are 30 frames per second, this can make large screens flicker.
Interlacing is a technique of improving the picture quality of a video signal without consuming extra bandwidth. In an interlaced scan, only half the screen is refreshed at a time. The video signal beam skips every other line, and fills in the missing lines on the next pass. Interlacing uses two fields to create a frame. One field contains all the odd lines in the image, the other contains all the even lines of the image. Interlacing causes a certain amount of visible flicker, but in live video it is hardly noticeable. When interlaced video is watched on a progressive monitor without deinterlacing, it exhibits 'combing' when there is movement between two fields of one frame.
Hybrid IP Set-Top Boxes enable to offer all their IP services with high-processing power. These powerful set-top-boxes offer access to internet/online TV, Video on Demand (VoD) and Over-The-Top services (OTT), as well as applications and other advanced services such as multi-screen (video transrating), wireless video streaming or Smart Home solutions.
A local area network (LAN) is a computer network covering a small physical area, like a home, office, or small group of buildings, such as a school, or an airport. The defining characteristics of LANs, in contrast to wide-area networks (WAN)s, include their usually higher data-transfer rates, smaller geographic area, and lack of a need for leased telecommunication lines.
Liquid Crystal Display. A display that consists of two polarising transparent panels and a liquid crystal surface sandwiched in between. Voltage is applied to certain areas, causing the crystal to turn dark. A light source behind the panel transmits through transparent crystals and is mostly blocked by dark crystals. Among its major features are its lightweight construction, its portability, and its ability to be produced in much larger screen sizes than are practical for the construction of CRT display technology. Its low electrical power consumption enables it to be used in battery-powered electronic equipment such as watches and clocks.
A video display which uses Light-Emitting Diodes. LEDs are used as indicator lamps in many devices, and are increasingly used for lighting. LEDs present many advantages over incandescent light sources (eg fluorescent) including lower energy consumption, longer lifetime, improved robustness, smaller size, faster switching, and greater durability and reliability. However, they are relatively expensive and require more precise current and heat management than traditional light sources.
The practice of transferring video content shot in a widescreen aspect ratio (eg 16:9) to standard-width video format (eg 4:3) while preserving the original aspect ratio. The resulting image has mattes (black bars) above and below it.
Describes an audio codec which is considered lossless â€“ meaning that the exact original data is able to be reconstructed from the compressed data. The latest multi-channel audio codecs are based on lossless compression algorithms with extremely high fidelity, such as Dolby TrueHD and DTS-HD Master Audio. Other Lossless audio codecs include FLAC, WAV and Monkeys Audio.
Luminance is the photometric measure of the brightness in a video picture. The luminance indicates how much luminous power will be perceived by an eye looking at the surface from a particular angle of view. Luminance is thus an indicator of how bright the surface will appear, eg if luminance is high, the picture is bright and if it is low the picture is dark.
Megabyte per second. A megabyte per second (MB/s or MBps) is a unit of data transfer rate equal to 8,000,000 bits per second, or 1,000,000 bytes per second, or 1,000 kilobytes per second, or 8 megabits per second.
Monochrome Display Adapter. MDA is a video display card introduced by IBM which did not have any graphics mode of any kind, but could display high resolution text characters. The MDA card featured a single monochrome text mode which could display 80 columns by 25 lines of high resolution text characters. This high character resolution was a feature meant to facilitate business and word processing use. MDA was introduced at the same time as the CGA card, which was aimed at PC users requiring bitmapped graphics and/or colour, rather than high resolution text.
Monkey's Audio is a file format for audio data compression. Being a lossless format, Monkey's Audio does not discard data during the process of encoding, unlike lossy compression methods such as AAC, MP3, Vorbis and Musepack. Data file compression is employed in order to reduce bandwidth, file transfer time, and/or storage requirements. A digital recording (such as a CD) encoded to the Monkey's Audio format can be decompressed into an identical copy of the original audio data.
MPEG-1 is a standard for lossy compression of video and audio. It is designed to compress VHS-quality raw digital video and CD audio down to 1.5 Mbit/s (26:1 and 6:1 compression ratios respectively) without excessive quality loss, making video CDs, digital cable/satellite TV and digital audio broadcasting (DAB) possible.
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission bandwidth
MPEG-4 is a method of defining compression of audio and visual (AV) digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG) (ISO/IEC JTC1/SC29/WG11) under the formal standard ISO/IEC 14496 – Coding of audio-visual objects. Uses of MPEG-4 include compression of AV data for web (streaming media) and CD distribution, voice (telephone, videophone) and broadcast television applications.
Multimedia is media and content that uses a combination of different content forms. The term is used in contrast to media which only uses traditional forms of printed or hand-produced material. Multimedia includes a combination of text, audio, still images, animation, video, and interactivity content forms. Multimedia can be recorded, played, displayed or accessed by information content processing devices, such as computers and electronic devices, but can also be part of a live performance. Multimedia (as an adjective) also describes electronic media devices used to store and experience multimedia content.
Multiview Video Coding (MVC) is an amendment to H.264/MPEG-4 AVC video compression standard developed with joint efforts by MPEG/VCEG that enables efficient encoding of sequences captured simultaneously from multiple cameras using a single video stream. MVC is intended for encoding stereoscopic (two-view) video, as well as free viewpoint television and multi-view 3D television. The Stereo High profile has been standardized in June 2009; the profile is based on MVC toolset and is used in stereoscopic Blu-ray 3D releases.MVC stream is backward compatible with H.264/AVC, which allows older devices and software to decode stereoscopic video streams, ignoring additional information for the second view.
NTSC is the analog television system used in most of North America, South America, Japan, South Korea, Taiwan, Burma, and some Pacific island nations and territories. The NTSC standard has the advantage of simplicity but there are several major drawbacks to its use such as limited video bandwidth which affects picture sharpness and faithfulness of colours. NTSC takes its name from the American committee which formulated it, the National Television Systems Committee.
A variation of the NTSC system used throughout Japan. With NTSC-J, black level and blanking level of the signal are identical (at 0 IRE), as they are in PAL, while in American NTSC, black level is slightly higher (7.5 IRE) than blanking level. Since the difference is quite small, a slight turn of the brightness knob is all that is required to correctly show the "other" variant of NTSC on any set as it is supposed to be; most watchers might not even notice the difference in the first place.
Unlike PAL, with its many varied underlying broadcast television systems in use throughout the world, NTSC colour encoding is invariably used with broadcast system M, giving NTSC-M.
Oxygen Free Copper wire used in high quality cable and wire. The oxygen content and impurities are removed during the manufacturing process, resulting in less signal distortion
An Organic Light Emitting Diode (OLED), is a light-emitting diode (LED) whose emissive electroluminescent layer is composed of a film of organic compounds. This layer of organic semiconductor material is formed between two electrodes, where at least one of the electrodes is transparent. Commonly used in television screens, computer monitors, small, portable system screens such as mobile phones and PDAs, watches etc. OLED displays do not require a backlight to function. Thus, they can display deep black levels and can be thinner and lighter than LCD panels and thier displays naturally achieve higher contrast ratios than either LCD screens using cold cathode fluorescent lamps (CCFL)s or the more recently developed LED backlights in conditions of low ambient light such as dark rooms.
Optical Imaging is a relatively modern development in touchscreen technology, in which two or more image sensors are placed around the edges (mostly the corners) of the screen. Infrared back lights are placed in the camera's field of view on the other side of the screen. A touch shows up as a shadow and each pair of cameras can then be triangulated to locate the touch or even measure the size of the touching object. This technology is growing in popularity due to its scalability, versatility and affordability, especially for larger units.
Over the Top (OTT) refers to video, television and other services provided over the internet rather than via a service provider’s own dedicated, managed IPTV network. OTT is delivered directly from provider to viewer using an open internet/broadband connection, independently of the viewer’s ISP, without the need for carriage negotiations and without any infrastructure investment on the part of the provider. OTT opens up a completely new way for operators to generate revenue from video on demand (VOD), catch-up TV and interactive applications. The clearest opportunity is for traditional TV distributors. With established brands, strong relationships and consumers’ trust, they are perfectly placed to deliver a seamless service that integrates online and traditional TV through a single device managed by a single operator.
PAL (Phase Alternation Line) is the analog television display standard that is used in Europe and certain other parts of the world. The term PAL is often used informally to refer to a 625-line/50 Hz (576i), television system, and to differentiate from a 525-line/60 Hz (480i) NTSC system
The majority of countries using PAL have television standards with 625 lines and 25 frames per second, differences concern the audio carrier frequency and channel bandwidths. Standards B/G are used in most of Western Europe, standard I in the UK, Ireland, Hong Kong and Macau, standards D/K in most of Central and Eastern Europe and Standard D in mainland China. Most analogue CCTV cameras are Standard D.
A substandard of PAL used by some countries, utilising 60Hz instead of 50Hz refreshing frequency. Some multi-standard equipment can take American NTSC and transcode the signal into PAL format. When operating in this mode most of them do not output a true (625/25) PAL signal but rather a hybrid of PAL and NTSC known as PAL-60 (or 'pseudo PAL') with "60" standing for 60 Hz, instead of 50 Hz. Some video game consoles also output a signal in this mode. Most newer television sets can display such a signal correctly but some will only do so (if at all) in black and white or with other problems. A PAL-60 signal is similar to an NTSC (525/30) signal but with a PAL chrominance subcarrier at 4.43 MHz (instead of 3.58) and with the PAL-specific phase alternation of the red colour difference signal between the lines.
In Brazil, PAL is used in conjunction with the 525 line, 29.97 frame/s system M, using (very nearly) the NTSC colour subcarrier frequency. Exact colour subcarrier frequency of PAL-M is 3.575611 MHz.
In Paraguay and Uruguay, PAL is used with the standard 625 line/50 fields per second system, but again with (very nearly) the NTSC subcarrier frequency. People in Uruguay, Argentina and Paraguay usually own TV sets that also display NTSC-M, in addition to PAL-N.
In Argentina, the PAL-Nc (combination N) variant is used. It employs the 625 line/50 field per second waveform of PAL-B/G, D/K, H, I, but with a chrominance subcarrier frequency of 3.582 MHz.
An extension of the PAL analogue broadcasting system for transmitting 16:9 programs without sacrificing vertical resolution. A standard PAL receiver will display the image in letterbox format with 432 active lines, while a PALplus receiver can use extra information hidden in the black bars above and below the image to recreate 576 lines of vertical resolution. A separate feature related to PALplus is ColourPlus, which improves colour decoding performance.
Picture and Picture (PAP), also commonly referred to as PBP (Picture by Picture), is a technique where two programs are displayed side-by-side on the screen, with the sound from one program being played through the speakers, and the sound from the other being sent to headphones. A somewhat similar function is called Picture and Text (PAT), where the screen is divided into one program and one teletext page.
Picture-In-Picture (PIP) is a feature of some television receivers and multimedia devices. Using the PIP function, one image is displayed on the full TV screen/monitor at the same time as one or more other programs are displayed in inset windows. Sound is usually from the main program only. The PIP function is useful in monitoring several video images simultaneously on one screen.
The smallest piece of data in a video image. The smaller the pixel size in an image, the greater the resolution.
In digital imaging, a pixel (or picture element) is a single point in a raster image. The pixel is the smallest addressable screen element, it is the smallest unit of picture which can be controlled. Each pixel has its own address. The address of a pixel corresponds to its coordinates. Pixels are normally arranged in a 2-dimensional grid, and are often represented using dots or squares. Each pixel is a sample of an original image, where more samples typically provide more-accurate representations of the original. The intensity of each pixel is variable. In color image systems, a color is typically represented by three or four component intensities such as RGB (red, green, and blue), or CMYK (cyan, magenta, yellow, and black).
Plasma is a display technology for thin flat display devices usually used for large TV screens. Plasma screen pixels are small cells sandwiched between two layers of glass that contain gases, which when electrically charged excite phosphors in the cell to emit light. Plasma displays should not be confused with LCDs, another lightweight flatscreen display using different technology. Plasma displays are bright, have a wide colour gamut, and can be produced in fairly large sizes - currently up to approximately 150 inches (measured diagonally). They have a very low-luminance "dark-room" black level compared to the lighter grey of the unilluminated parts of an LCD screen.
A speaker designed to reproduce a range of very low frequencies only. A stand-alone component powered by a built in amplifier.
Progressive scan is a method for displaying, storing or transmitting moving images in which all the lines of each frame are drawn in sequence. The video signal beam does not skip alternate lines, but fills in each line every time, which tends to render smoother motion sequences. This is in contrast to the interlacing used in traditional television systems where only the odd lines, then the even lines of each frame (each image now called a field) are drawn alternately. Advantages of progressive scan include a higher vertical resolution than interlaced video with the same frame rate, an absence of visual artifacts associated with interlaced video of the same line rate, and better results when scaling to higher resolutions than equivalent interlaced video, such as upconverting 480p to display on a 1080p HDTV. A disadvantage of progressive scan is that it requires higher bandwidth than interlaced video that has the same frame size and vertical refresh rate.
A port type developed by IBM for the purpose of connecting a keyboard or mouse to a PC. The PS/2 port has a mini DIN plug containing 6 pins. Following the release of USB keyboards, PS/2 keyboards and mice have become less popular.
QSXGA (Quad Super Extended Graphics Array) is a display resolution of 2560Ã—2048 pixels with a 5:4 aspect ratio. Grayscale monitors with a 2560Ã—2048 resolution, primarily for medical use.
QSXGA+ (Quad Super Extended Graphics Array +) is a display resolution of 2800Ã—2100 pixels with a 4:3 aspect ratio. Grayscale monitors with a 2800Ã—2100 resolution.
QUXGA (Quad Ultra Extended Graphics Array) describes a display standard that can support a resolution up to 3200 x 2400 pixels, assuming a 4:3 aspect ratio.
The Quarter Video Graphics Array (also known as Quarter VGA, QVGA, or qVGA) is a popular term for a computer display with 320 Ã— 240 display resolution. QVGA displays are most often used in mobile phones, PDAs and some handheld game consoles. Often the displays are in a "portrait" orientation (i.e., taller than they are wide, as opposed to "landscape") and are referred to as 240 Ã— 320.
The QXGA, or Quad eXtended Graphics Array, display standard is a resolution standard in display technology. Their high pixel counts and heavy display hardware requirements mean that there are currently few CRT and LCD monitors which have pixel counts at these levels. These terms are currently relegated to the highest-end consumer computer display hardware for those buying LCD
A type of electrical connector commonly used to carry audio and video signals. In the most normal usage, cables have a standard plug on each end, consisting of a central male connector, surrounded by a ring. Devices mount the jack, consisting of a central hole with a ring of metal around it. Plugs and sockets on consumer equipment are conventionally colour-coded to aid correct connections. For example yellow for composite video, red for the right channel, and white or black for the left channel of stereo audio. This trio (or pair) of jacks can be found on the back of almost all audio and video equipment. The name 'RCA' derives from the Radio Corporation of America, which introduced the design by the early 1940s to allow mono phonograph players to be connected to amplifiers. RCA Plugs are also commonly referred to as Phono Plugs.
The number of times in a second that display hardware draws the data, refreshing the image. Refresh rates for broadcast TV vary by region â€“ for example, European HD systems run at 50 Hz. On CRT displays, increasing the refresh rate decreases flickering, thereby reducing eye strain. However, if a refresh rate is specified that is beyond what is recommended for the display, damage to the display can occur. Refresh Rate is distinct from the measure of frame rate in that the refresh rate includes the repeated drawing of identical frames, while frame rate measures how often a video source can feed an entire frame of new data to a display.
Resistive touchscreens are composed of two flexible sheets coated with a resistive material and separated by an air gap or microdots. When contact is made to the surface of the touchscreen, the two sheets are pressed together, registering the precise location of the touch. Because the touchscreen responds to pressure on its surface, contact can be made with a finger or any other pointing device. Resistive touchscreens typically have high resolution (4096 x 4096 DPI or higher), providing accurate touch control.
The density of lines and dots per line, which make up a visual image. The number of pixels measures resolution. The more lines and dots means a sharper and more detailed picture. Regular TV has about 200,000 pixels, While, HDTV (1080 vertical pixels and 1920 horizontal pixels) has more then 2 million pixels creating the image.
Radio frequency (RF) radiation is a subset of electromagnetic radiation with a wavelength of 100 km to 1 mm, which is a frequency of 3 kHz to 300 GHz, respectively. This range of electromagnetic radiation constitutes the radio spectrum and corresponds to the frequency of alternating current electrical signals used to produce and detect radio waves. RF can refer to electromagnetic oscillations in either electrical circuits or radiation through air and space. Like other subsets of electromagnetic radiation, RF travels at the speed of light.
An electrical connector designed to work at radio frequencies in the multi-megahertz range. RF connectors are typically used with coaxial cables and are designed to maintain the shielding that the coaxial design offers. Better models also minimise the change in transmission line impedance at the connection.
Primarily used to convert the composite video output from a DVD to a radio frequency operating on Channel 3 or 4. The output from the RF Modulator is an "F" connector.
Interference caused by CB radios, radio stations, microwave ovens, power lines, cellular phones, etc. which can cause noise and distortion affecting sound and audio quality for audio/video components.
A standard used for referencing coaxial cables, such as RG6/U or RG59/U, RG is a military standard for Radio Guide.
A colour model in which Red, Green, and Blue light are added together in various ways to reproduce a broad array of colours. Computer monitors and TVs emit colour as RGB light. Although all colours of the visible spectrum can be produced by merging red, green and blue light, monitors are capable of displaying only a limited gamut of the visible spectrum. Typical RGB input devices are colour TV and video cameras, image scanners, and digital cameras. Typical RGB output devices are TV sets (CRT, LCD, plasma, etc.), computer and mobile phone displays, and video projectors. Colour printers, on the other hand, are not RGB devices, but subtractive colour devices - typically CMYK colour model where secondary colours (cyan, magenta and yellow) are used to simulate the colours required, with black (K) added to help CMY reproduce rich blacks and shadows.
A RGB signal where the synchronisation impulses that keep the picture fully synchronised (all colours at the right time) are found in separate cables. RGB has three wires and HV adds two more wires.
An analog video signal that carries video data as two separate signals: luma (luminance) and chroma (colour), to reduce the possibility of interaction. This differs from composite video, which carries picture information as a single lower-quality signal, and component video, which carries picture information as three separate higher-quality signals. S-Video was created to try and avoid the picture degradation that can occur with composite video. S-Video carries standard definition video (typically at 480i or 576i resolution), but does not carry audio on the same cable.
Sony/Philips Digital Interconnect Format (more commonly known as Sony Philips Digital InterFace). S/PDIF is a digital interface designed to enable digital equipment to transfer digital information with minimal loss. A common use for the S/PDIF interface is to carry compressed digital audio. Connectors are either electrical coaxial cable (with RCA plug) or optical fibre (TOSLINK).
for DSS systems, used in multiple LNB installations for reception of multiple satellite signals on a single feed line connecting to several satellite receivers.
Surface Acoustic Wave (SAW) technology uses ultrasonic waves that pass over the touchscreen panel. When the panel is touched, a portion of the wave is absorbed. This change in the ultrasonic waves registers the position of the touch event and sends this information to the controller for processing. Must be touched by a finger, gloved hand, or a soft-tip stylus. Because the panel is all glass there are no layers that can be worn, giving this technology a high durability factor as well as great clarity. However SAW touchscreen panels are not completely sealable, and contaminants on the surface (eg dirt, dust) can interfere with the functionality of the touchscreen.
A scan converter is a device which changes the vertical / horizontal scan frequency of a video signal for different purposes and applications. It is generally used to convert a video signal into a format compatible with a specific type of display, for example converting a digital computer signal into a format suitable for viewing on a conventional analog television set. The application of scan conversion is wide and covers video projectors, cinema equipment, TV and video capture cards, standard and HDTV televisions, LCD monitors and many different aspects of picture and video processing.
SCART is a 21-pin analog connection standard for connecting audio-visual (AV) equipment together. Also known as Euroconnector or Peritel. In Europe, SCART is the most common method of connecting audio-visual equipment together, and has become a standard connector for such devices. It is far less common elsewhere in the world. Simplicity of connections is the main advantage of the SCART system, however, it is not recommended for professional use as the physical connection is quite weak and signal leakage is too high. SCART is becoming obsolete with the introduction of new digital standards such as HDMI, which can also carry high-definition content and multichannel audio.
Serial Digital Interface (SDI) is a standard for digital video transmission over coaxial cable. The most common data speed is 270 megabits per second (Mbps), however speeds of up to 540 Mbps are theoretically possible. Standard 75-ohm coaxial cable is used. SDI is designed for operation over short distances (less than 300m with coaxial cable); due to high bitrates making it inappropriate for long-distance transmission. Standard-definition television (SDTV) is a television system that has a resolution that meets standards but not considered either enhanced-definition television (EDTV) or high-definition television (HDTV). The term is usually used in reference to digital television, in particular when broadcasting at the same (or similar) resolution as analog systems. Examples of Standard Definition video modes are 480i, 480p, 576i and 576p.
Standard-definition television (SDTV) is a television system that has a resolution that meets standards but not considered either enhanced-definition television (EDTV) or high-definition television (HDTV).The term is usually used in reference to digital television, in particular when broadcasting at the same (or similar) resolution as analog systems. Examples of Standard Definition video modes are 480i, 480p, 576i and 576p.
SECAM is an analog colour television system first used in France. SECAM can also be found in parts of Greece, Eastern Europe, Russia, Africa and a few other parts of the world. SECAM differs from the other colour systems by the way the R-Y and B-Y signals are carried. Firstly, SECAM uses frequency modulation to encode chrominance information on the sub carrier. Second, instead of transmitting the red and blue information together, it only sends one of them at a time, and uses the information about the other colour from the preceding line. Because SECAM transmits only one colour at a time, it is free of the colour artifacts present in NTSC and PAL resulting from the combined transmission of both signals.
Converts video signal (either analog cable, digital cable or HDTV) for display on a television. HDTV- Ready (without built-in HDTV tuner) televisions must be connected to a compatible HDTV tuner set-top box to receive digital television programs.
A measure that describes how "clean" a signal is. Measures the strength of an audio or video signal versus the noise and interference. This measure is in dB.
A two lead cable with wires that carry amplified audio signal from the audio/video receiver to the speakers. One channel is positive (+) and the other is negative (-).
The distribution of sound resulting from digital decoding. May be 5.1, which is front speakers (right and left), rear speakers (right and left), center channel speaker, and a powered subwoofer. May be 6.1, which is front speakers (right and left), front center channel speaker, rear speakers (right and left), rear center channel speaker, and a powered subwoofer.
Super Video Graphics Array or SVGA. Originally released as an extension to the VGA standard, the term SVGA normally refers to a resolution of 800 x 600 pixels. On paper, the original Super VGA was to be succeeded by Super XGA, but in practice the industry soon abandoned the attempt to provide a unique name for each higher display standard, and almost all display systems made between the late 1990s and the early 2000s are classed as Super VGA. Monitor manufacturers sometimes advertise their products as XGA or Super XGA. In practice this means little, since all Super VGA monitors manufactured since the later 1990s have been capable of at least XGA and usually considerably higher performance. SVGA uses a VGA connector as the original standard.
An electric quality test procedure performed by network analyzer test equipment measuring coaxial or network cables at various frequencies between 1 MHz and 2.6 GHz. Measurements include attenuation (electrical signal degradation), reflection (return loss), and noise (cross talk).
SXGA is an acronym for Super eXtended Graphics Array referring to a standard monitor resolution of 1280x1024 pixels. This display resolution is the "next step" above the XGA resolution. The 1280Ã—1024 resolution is not the standard 4:3 aspect ratio, but 5:4.
SXGA+ stands for Super eXtended Graphics Array Plus and is a computer display standard. An SXGA+ display is commonly used on 14 inch or 15 inch laptop LCD screens with a resolution of 1400 Ã— 1050 pixels.
A device which is used to reduce or eliminate errors caused by mechanical instability present in analog recordings on mechanical media. Without time base correction, a signal from a videotape recorder or videocassette recorder cannot be mixed with other, more time stable devices found in video studios. TBCs are also used to synchronise two video sources to allow mixing.
A variant of Liquid Crystal Display (LCD) which uses thin-film transistor (TFT) technology to improve image quality. Generally used in the manufacturing of flat computer screens and video screens.
TOSLINK (Optical Cable) is a standardised optical fiber connection system. Its most common use is in consumer audio equipment, where it carries a digital audio stream. It can often be found on DVD players and some game consoles to connect the digital audio stream to Dolby Digital/DTS decoders.Toshiba originally created TOSLINK (Toshiba Link) to connect their CD players to their receivers for PCM audio streams, and it was soon adopted by other manufacturers.
Truecolor is a method of representing and storing graphical image information (especially in computer processing) in an RGB colour space such that a very large number of colours, shades, and hues can be displayed in an image, such as in high quality photographic images or complex graphics. Usually, truecolor is defined to mean at least 256 shades of red, green, and blue, for a total of at least 16,777,216 colour variations. Truecolor can also refer to an RGB display mode that does not need a colour look-up table.
Ultra High Definition Video (UHDV) is an experimental digital video format, currently proposed by NHK of Japan and British Sky Broadcasting and represents an intermediate format also referred to as Quad TV and is mid-way between the HDTV and UHDTV.
Underwriters Laboratory, a listing service for electrical and electronic equipment. www.ul.com
Ultra HD (also known as “Ultra High Definition” / “Super Hi-Vision” / “Ultra HDTV” / “UHD” / “UHDTV” / “4K” / “8K”), is a video format conceptualized by the Japanese public broadcasting network.On October 17, 2012, The Consumer Electronics Association (CEA) announced that the official term “Ultra HD” would be used for any display with a 16 x 9 ratio with at least 1 digital input cable carrying a minimum resolution of 3,840 x 2,160 square pixels.
Universal Serial Bus. A peripheral interface standard used to establish communication between devices and a host controller (usually personal computers). USB is intended to replace many varieties of serial and parallel ports. USB can connect computer peripherals such as mice, keyboards, digital cameras, printers, personal media players, flash drives, and external hard drives. For many of those devices, USB has become the standard connection method.
UXGA is an abbreviation for Ultra eXtended Graphics Array referring to a standard monitor resolution of 1600x1200 pixels, which is exactly quadruple the default resolution of SVGA (800x600). Dell Computer refers to the same resolution of 1,920,000 pixels as UGA. It is generally considered to be the next step above SXGA (1280x960 or 1280x1024)
Video Electronic Standards Association (VESA) is a group of manufacturers formed to establish and maintain industry wide standards for video cards and monitors. VESA's initial goal was to produce a standard for 800x600 SVGA resolution video displays. Since then VESA has issued a number of standards, mostly relating to the function of video peripherals in personal computers.
Video Graphics Array (VGA) refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, through its widespread adoption has also come to mean either an analog computer display standard, the 15-pin D-subminiature VGA connector or the 640Ã—480 resolution itself.
The voltage between two points is a short name for the electrical force that would drive an electric current between those points. Specifically, voltage is equal to energy per unit charge. In the case of static electric fields, the voltage between two points is equal to the electrical potential difference between those points. Voltages as low as 50 volts can lead to a lethal electric shock under certain circumstances.
A wide area network (WAN) is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries. This is in contrast with personal area networks (PAN)s, local area networks (LAN)s, campus area networks (CAN)s, or metropolitan area networks (MAN)s which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively.
WAVE or WAV, short for Waveform Audio File Format, (rarely also named Audio for Windows) is a Microsoft and IBM audio file format standard for storing an audio bitstream on PCs.
WHSXGA, an abbreviation for Wide Hex[adecatuple] Super Extended Graphics Array, is a display standard that can support a resolution up to 6400 x 4096 pixels, assuming a 1.56:1 aspect ratio. The name comes from the fact that it has sixteen (hexadecatuple) times as many pixels as an WSXGA display.
WHUXGA an abbreviation for Wide Hex[adecatuple] Ultra Extended Graphics Array, is a display standard that can support a resolution up to 7680 Ã— 4800 pixels, assuming a 16:10 aspect ratio. The name comes from the fact that it has sixteen (hexadecatuple) times as many pixels as a WUXGA display. A WHUXGA image consists of 36,864,000 pixels (approximately 37 megapixels). A monitor of 7680 Ã— 4320 would also qualify as a WHUXGA display. UHDV video requires a display of similar resolution (7680 Ã— 4320) for properly displaying UHDV content, which is 16 times the resolution (four times the horizontal resolution and four times the vertical resolution) of 1080p "Full HD".
WHXGA an abbreviation for Wide Hex[adecatuple] Extended Graphics Array is a display standard that can support a resolution of roughly 5120Ã—3200 pixels with a 16:10 aspect ratio. The name comes from the fact that it is a wide version of HXGA, which in turn has sixteen (hexadecatuple) times as many pixels as an XGA display. Only high-end digital cameras capable of rendering images at this resolution. It would require four WQXGA devices to display at this resolution.
WQSXGA (Wide Quad Super eXtended Graphics Array) describes a display standard that can support a resolution up to 3200 x 2048 pixels, assuming a 1.56:1 (25:16) aspect ratio.
WQUXGA (Wide Quad Ultra Extended Graphics Array) describes a display standard that can support a resolution up to 3840 x 2400 pixels, assuming a 16:10 aspect ratio.
WQXGA (Wide Quad eXtended Graphics Array) is a display resolution of 2560Ã—1600 pixels with a 16:10 aspect ratio or 2560Ã—1440 with 16:9 aspect ratio (1440p). The name comes from the fact that it is a wide version of QXGA and has four times as many pixels as an WXGA display.
WSXGA+ stands for Widescreen Super eXtended Graphics Array Plus and is a computer display standard. A WSXGA+ display is commonly used on Widescreen 20", 21", and popular 22" LCD monitors from numerous manufacturers (and a very small number of 19" widescreen monitors), as well as widescreen 15.4" and 17" laptop LCD screens like the Thinkpad T61. The resolution is 1680Ã—1050 pixels (1,764,000 pixels) and has a 16:10 aspect ratio. WSXGA+ is the widescreen version of SXGA+, but it is not approved by any organization.
WUXGA stands for Widescreen Ultra eXtended Graphics Array and is a display resolution of 1920Ã—1200 pixels (2,304,000 pixels) with a 16:10 screen aspect ratio. It is a wide version of UXGA, and is appropriate for viewing HDTV content.
Wide VGA or WVGA an abbreviation for Wide Video Graphics Array is any display resolution with the same 480 pixel height as VGA but wider, such as 800Ã—480, 848Ã—480, or 854Ã—480. It is a common resolution among LCD projectors and later portable and hand-held internet-enabled devices.
Wide XGA (WXGA) is a set of non standard resolutions derived from the XGA display standard by widening it to a wide screen aspect ratio. WXGA is commonly used for low-end LCD TVs and LCD computer monitors for widescreen presentation. WXGA is generally understood to refer to a resolution of 1366Ã—768, with an aspect ratio of 16:9 hhen referring to televisions and other monitors intended for consumer entertainment use. WXGA is most commonly used to refer to a resolution of 1280Ã—800 pixels with an aspect ratio of 16:10 when referring to laptop displays or monitors intended primarily as computer displays.
WXGA+ is a non-standard computer display resolutions term refering to a resolution of 1440x900. WXGA+ can be thought of as an enhanced version of WXGA with more pixels, or as widescreen variants of SXGA. The aspect ratios of each are 16:10
Extended Graphics Array. A display standard with 1024Ã—768 pixels display resolution. The initial version of XGA expanded upon IBM's VGA, adding support for two resolutions: 800Ã—600 pixels with high colour (16 bits per pixel), and 1024Ã—768 pixels with a palette of 256 colours (8 bits per pixel). XGA should not be confused with VESA's EVGA (Extended Video Graphics Array) which was released at a similar time.
A family of colour spaces, used in some HD applications, where colour is expressed using a luma component plus red and blue chroma components, rather than by describing absolute color values, as in the RGB colour model. The difference between YCbCr and RGB is that YCbCr represents color as brightness and two colour difference signals, while RGB represents colour as red, green and blue. In YCbCr, the Y is the the brightness (luma), Cb is blue minus luma (B-Y) and Cr is red minus luma (R-Y). The analog counterpart of YcbCr is YpbPr.
YPbPr component video is the analog counterpart of digital component video, which is YCbCr. Whereas YPbPr uses three cables between video equipment, YCbCr uses a single cable. The three cables used in YPbPr connection represent higher quality than the single-wire composite cable commonly used to hook up video equipment, because the brightness and colour components of the signal are maintained separately.