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The terms used in this industry can be a bit confusing if you have not heard them before. The following is a list of common ones that you may come across. |
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3:2 Pulldown - Is a method for transferring 24-frame/second film images to 60-field/second video. Film frames are transferred to three video fields followed by two video fields for the next frame. This sequence is repeated as follows 3, 2, 3, 2, 3, 2.... |
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480i - Is the resolution of standard definition television. This can either be a 16:9 format or 4:3 format. |
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480p - Is a lower resolution HDTV format or the output from a progressive DVD player. This can either be a 16:9 or 4:3 format. |
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720p - Is a progressive HDTV format. This is a 16:9 aspect ratio (rectangular) format. |
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1080i - Is an interlaced HDTV format. This is a 16:9 aspect ratio (rectangular) format. |
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A/D - Is an analog signal to digital signal converter. This is used to transform a signal which is based on a continuous voltage and/or frequency to ones and zeros. |
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Aliasing - Is when a wider spaced line pattern is created from a finer line pattern. This is caused by improper filtering and/or insufficient resolution of the display relative to the source. |
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Artifacts - Are false information that can be present in an image. They can appear as spots, patterns, lines, jagged edges or any other localized imprefection. These can be caused by signal processing, electrical noise or optical imperfections. |
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ATSC - Is the name given to the 8-VSB broadcast standard for HDTV in the USA. It is also an abbreviation for the "Advanced Television Systems Committee" that established the standard. |
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Blu-Ray - Is a new
HDTV recorded video format with improved audio. |
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BNC Connector - Is an abbreviation for Bayonet Neill Concelman connector. This connector has a pin in the center that is connected to the wire in the cable and a metal tube connected to the cable shield. An outer ring on the male connector locks it to any female connector. These are typically found in higher quality products where a true 75 ohm connection is desired. This is the best analog connector type to use with video. |
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Brightness - Is an adjustment in the user menu for setting the intensity of black. When brightness is set correctly the lowest level signal above black should be barely visible. |
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Burn-In - Is an artifact that is caused by having an image on a screen too long. Plasma and CRT have the biggest problem with this and the damage is usually permanent on these devices. Other technologies can suffer a similar problem with image retention, but it is not normally permanent. |
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CIE - The International Commission on Illumination (Commission Internationale de l'E'clairage), this is an international organization concerned with color and color measurement. The CIE established an international standard for primary colors in 1931. This standard allows all colors to be defined as a combination of three primary colors (red, green, blue). |
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CRT - Is an abbreviation for cathode ray tube display. A CRT uses an electron beam to excite phosphorus to emit light to generate the image. |
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Chromatic Aberration - Is a distortion of the picture that is caused by the light not being focused properly. This is caused by the lens system spreading the light like a rainbow. This is only found in displays the use lenses to project the image. Calibration cannot influence this, but display selection can. Typically more expensive display devices use higher quality lenses to reduce this effect. |
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Chroma Delay - Is a video artifact that appears as the color information shifted to the left or right of the black and white. This is caused by timing errors in the signals. |
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Color - Is an adjustment in the user menu for setting the intensity of colors. When color is set correctly the intensity of blue is the same as its intensity in white. |
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Color Analyzer - Is a device that can measure the color of light. |
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Color Bars - Are a standard test pattern with white, yellow, cyan, green, magenta, red and blue bars that are used to make the color calibration on a display device. |
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Color Decoder - How color is translated from an input signal into what is displayed on your screen. Default factory settings for this frequently result in skin tones that are too red (red push). This is one of the key areas calibration is intended to improve. |
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Color Wheel - Is a disk that is subdivided axially into multiple segments. Each segment is typically either red, blue, green or white. A color wheel is used in combination with an LCoS or DLP device to reduce the cost of implementation. |
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Component Video - Are three cables for transmitting an analog video signal. This type of connection is capable of carrying the complete resolution of HDTV and NTSC. |
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Composite Video - Is a single cable for transmitting an analog video signal. The resolution of this connection is limited in its ability to transmit detailed color information for NTSC compatible images. |
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Contrast or Picture - Is the user mode setting that sets the intensity of white. When this is set correctly your display will not shift in color, gamma or geometry at high levels. Too high of contrast levels can also cause burn-in to be a greater problem. |
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Contrast Ratio (ANSI) - Is the ratio of light output from white sections and dark sections of a display with a checkerboard like pattern. This is typically much lower than the on/off contrast ratio. |
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Contrast Ratio (On/Off) - Is the ratio of light output when the screen is white versus when it is black. These measurements are frequently exaggerated by manufacturers making published figures less useful. |
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Color Temperature - Is a user menu setting that refers to the color of gray. 6500K is the target color temperature, but most displays do not come properly calibrated to match it. Settings can also be referred to as cool, warm or neutral. Neutral or warm are most likely to be closest to D65. |
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D65 - Is the standard point (x=0.3127, y=0.329) in perceptual color space used to define the standard for gray for NTSC and HDTV video. Your display will not accurately display the image if it does not closely match D65 when no color is present in the image. This is due to the way an image is created by painting colors on top of the base gray image. The D65 image in essence is the color of the canvas that your TV uses to display a picture. The closer an image is to gray the more it will be in error if your display is not calibrated to D65. A quality display calibration must include verification or calibration that a display adheres to the D65 standard. |
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De-interlace - Is an educated guess that is made to video interlaced signals to reconstruct the missing information. |
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Delta C - Are relative errors in color measurements. |
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Delta E - Are relative errors in color measurements. |
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D-ILA - Is an abbreviation for Direct-drive Image Light Amplifier which is JVC's proprietary LCoS technology. |
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D-Theater - Is an encrypted prerecorded format that is found on D-VHS. This format offers exceptional quality for prerecorded content. |
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D-VHS - Is a digital version of VHS that is more like a digital tape backup using a VHS tape form factor. |
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Display Device - Is anything that can be used to view a video or film. This would include an ordinary CRT television to a front projector. |
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Direct View - Is a type of display that does not use a lens system to create an image. CRT, LCD and plasma displays are common types of these. |
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DLP - Is an abbreviation for digital light processing which is Texas Instrument's proprietary technology. This technology uses a large number of very small mirrors that represent pixels. These mirrors move rapidly on and off to change to intensity of each pixel. The color of each pixel can be based on an individual DLP for each color primary or a single DLP device that uses a color wheel to change the color. |
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DVD - Is an abbreviation for Digital Video/Versatile Disc and was launched by The Digital Entertainment Group. |
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DVR - Is an abbreviation for digital video recorder. This is the same thing as a PVR. |
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DVI - Is a single cable that is used to carry digital video data. DVI can have picture degradation from poor connections or cables because it does not include error correction or detection. |
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Firewire - Is another name for IEEE-1394. |
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Front Projector - Is a display type that uses a lens to project on a screen. This is the type of display device that professional theaters use. Home theaters are based on CRT, DLP, LCD and LCoS implementations instead of the film that most theaters use. |
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Gamma - Is a measurement of the how the image brightness changes with the input signal level. |
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Geometry - Is how square the image is. Some display types liked plasma and LCD panels do not have problems with this. Direct view CRT and rear projection sets frequently have problems that can be improved with calibration. |
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Grayscale or Greyscale or Gray Scale - Is the color of gray over different intensity levels. Calibration of this requires an accurate color measurement tool. These include optical comparators, spectra radiometers and color analyzers. |
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HD-DVD - Is the next generation high definition DVD player
with improved audio. |
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HDCP - Is an encryption technique used to protect video content. This feature is required to ensure future compatibility with HDTV sources (cable, satellite, HD-DVD, Blu-Ray). |
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HDMI - Is a single cable that is used to carry digital audio and video data. The HDMI connector can have problems due to cable stress on the connector. |
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HTPC - Is an abbreviation for home theater personal computer. These computers are used in conjunction with a display to project film/video images as well as allowing the display to act as a large monitor. Differences in computer and video standards cause problems with HTPC's having equivalent picture quality to the best video sources. HTPC's can also be less friendly to use and may periodically glitch. |
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Hue - Is the intensity of blue in magenta and cyan. When set correctly the intensity of blue in cyan and in magenta is identical. |
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IEEE-1394 - Is a single thin cable that is used to transmit video and audio digitally. IEEE-1394 is a bidirectional communication that allows remote control of connected devices. This type of connection frequently works the best, but many display devices do not have it and some devices may not be supported by those that do |
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Image Artifacts - Are defects in the image that can be caused by the display type or image processing. |
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Image Retention - Is similar to burn-in and is caused by displaying the same image on a screen too long. LCoS and LCD can suffer from this, but it does not tend to be permanent. |
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Interlaced Display - Is a display that refreshes half of the screen at a time. A CRT display is an interlaced display. |
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Inverse Telecine - Is a process that can be applied to a video source that can recreate the individual film frames if the source used what is referred to as telecine or 3-2 pulldown process to create the interlaced image. The inverse telecine can be perfect, but problems with DVD authoring and inherent problems with the color compression process can cause image artifacts. |
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ISFccc - Is a certification from
the Imaging Science Foundation that may include controls
that require an ISF certified technician to adjust. |
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Judder - Is an image artifact that appears as unsmooth pans. This is caused by the inverse telecine process normally operating at 60 Hz in the USA. To fit 24 frames/second into a 60 frame/second system requires alternating the frame squence 3,2,3,2.... Processing at a multiple of 24 (i.e. 72 Hz) allows each frame to be on the screen for the same amount of time. |
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LCD - Is an abbreviation for liquid crystal display. This type of display uses electricity to restrict the light that passes through crystal structure. |
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LCoS - Is an abbreviation for liquid crystal on silicon. This type of display uses electricity to change the amount of light that is reflected from the crystal structure. |
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Macro Blocking - Is an image artifact that is caused by a combination of MPEG compression, image enhancement and the display performance. It appears to be a sea of small blocks that dance in an image with similar image intensity or color. Plasma displays and a DVD player with Faroudja processing is one of the most common combinations that can have this problem. |
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Motion Adaptive - Is a type of de-interlacing that guesses based on the motion as to what is missing. |
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MPEG - Is the Moving Picture Experts Group which is in charge of the development of standards for coded representation of digital audio and video. Several of the digital compression techniques in common use were developed by this group. |
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Multipath - Is when a broadcast radio signal reaches the receiver multiple times because it is reflected off of objects and the reflected signal is delayed. This creates ghosting (double images) in analog broadcasts, but it can confuse digital receivers because it does not which one is the primary data stream. |
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NTSC - Is an abbreviation for National Television System Committee. This is the standard for television broadcasts in the USA that is currently in use for regular television. |
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OTA - Is an abbreviation for off the air. This is short hand for broadcast television. |
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Overscan - Is a measurement of what part of the picture that is being sent to the TV that is not being displayed. Excessive overscan can cause you to miss seeing 5 to 10 percent of the picture. A good indication of this being a problem is when you see sporting event clocks and scores that are only partially displayed. |
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PAL - Is an abbreviation for Phase Alternation by Line. This is one of the common alternative video standards that is used in Australia and Europe. |
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Plasma Display - Is a display that uses an electrically excited gas that glows to display an image. |
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Primary Color - Is one of three colors used to display an image. The primary colors of light are red, green and blue. This combination of colors can create a very wide range of colors. |
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Red Push - A color decoder that is set incorrectly to emphasize red in the picture. |
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RF Video - Is how analog cable and analog OTA is distributed. |
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Polarizer - Is a light filter used in an LCD projection system. LCD blocks polarized light which the polarizer filters so that it will work. |
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Posturization - Is an artifact found in some displays. When a scene has changes in intensity that should appear smooth, but instead appear as obvious steps is posturization. |
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PQ - Is an abbreviation for picture quality typically found in use on the internet. |
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Progressive Display - This type of display refreshes the entire image at once. This is typically once every 60 seconds for USA video. This is the preferred display type for viewing film images and is generally considered superior to interlaced for all image types. |
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PVR - Is an abbreviation for personal video recorder. These are a convenient way of time shifting your TV viewing. They record the video to a hard disk like a computer. Many cable systems offer this option and all satellite systems offer this option. |
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Rainbows - Is an artifact that can be caused by the use of a color wheel. Rainbows commonly appear as a momentary burst of color when it should not be present. This is easiest to see when an image is has very bright objects on a black background. |
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RCA Connector - Is the most common type of connection used for video and audio. This type of connector does not have the best performance, but it can be very good. |
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RGB - Is a method used to encode a video data. RGB and component are the most common encoding systems used in consumer video. All current consumer devices convert the incoming video to RGB for final display. |
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RPTV - Is an abbreviation for rear projection television. This type of television uses a mirror in the back of it and a lens system to project the image onto a transparent screen facing the viewer. This type of display can use DLP, LCD, LCoS or CRT technology. |
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S-Video -Is a single cable used to carry an analog video signal. This type of connection can be superior to composite video, but it depends on the comb filter found in the source versus the display. The electrical properties of this connector and cable are not quite as good as those used for composite video. |
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Scalar - Is a device that is used to change the resolution of a source (DVD, HD Tuner...) to match that of a display. These are usually inside of the display, but high quality ones can also be separate. |
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SCART - Is an abbreviation for Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs. This is a video connection found in Europe. |
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SD - Is an abbreviation for standard definition typically found in use on the internet. |
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Service Mode or Service Menu - Is a hidden mode found in most video devices that is used by technicians to improve the picture quality. |
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SDE - Is an abbreviation for screen door effect. This is an artifact that makes it look like you are looking through a screen door. This is caused by the pixels being surrounded by a grid. LCD has this worse than any other technology. The problem is more evident the closer you set to the screen or the larger the picture is. |
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SDI - Is a single video cable that is used to carry a digital video signal. This type of connection is normally found on commercial equipment, but is sometimes used with modified DVD players and external scalars. |
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SECAM - Is an abbreviation for Systeme Electronique Couleur Avec Memoire. This is the French video standard. |
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Signal Generator - Is a device that is used to generate test images for display calibration. These devices are useful in calibrating a display to industry standards. |
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Sharpness - Is a user menu adjustment that determines how edgy the picture looks. Proper sharpness will result in a smooth transition from dark to white with no ringing. This frequently requires service mode adjustment to remove edge enhancements. |
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SMPTE - Is an abbreviation for The Society of Motion Picture and Television Engineers. This organization sets many of the standards associated with film production. |
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Spatial Dithering - Is a method of rendering the appearance of a smooth image on a display with a device that is only binary. DLP uses this method to draw an image on the screen. |
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Spectroradiometer - A device that measures the color of light by dividing it into many wavelength segments. This is the most accurate way to measure color. |
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STB - Is an abbreviation for set top box. This covers a broad range of products that convert a broadcast, cable or satellite signal to one that your display device can use. |
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SXRD - Is an abbreviation for Silicon Crystal (X-tal) Reflective Display which is Sony's proprietary LCoS technology. |
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User Menu - Is the menu that you can access with your remote to adjust the setup of your display. |
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VGA - Is a single cable that is used to carry an analog video signal. This type of connection is capable of carrying the complete resolution of HDTV and NTSC. It is typically used for connection with a computer. |
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