Television and Video Glossary -- E-G
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Numbers are treated as if they were spelled out in words, for example "9-Eyes" would be alphabetized as "nine...". Punctuation marks are treated as spaces, for example "R-Y" would be alphabetized with "R" as an initial, preceding words beginning with "R". Acronyms such as "RGB" are alphabetized as words, not initials. Generally acronyms which are names (NTSC, SMPTE) have the definition alongside while acronyms which are not names (AFC, RAM) have the definition alphabetized with the spelled out meaning of the acronym.
Easter Egg -- A special feature in a DVD video program which does not play in sequence with the main program and whose title or method of access is often obscurely located (quite hidden). Often the reference to it in an on-screen menu is a small icon that is selected using arrow keys on a remote control and which may be circular or oval shaped.
Edge Enhancement -- A method of postprocessing to make boundaries (or edges) between objects appear sharper although resolution is not increased. Typically a darker pixel next to a light pixel is made slightly darker, and/or a lighter pixel next to a dark pixel is made slightly lighter. Done to excess, edge enhancement may make objects appear to have halos around them.
Edge Lit -- Refers to the first LCD based video screens with a white panel for a back light for the LCD pixel dynamic stencil. The panel is illuminated by (at first) fluorescent tubes or elements or (later) LEDs along the panel edges, usually the top and bottom. This technology has been largely superceded by LEDs for back lighting distributed over the entire surface of the back light panel, giving more even illumination but a body or cabinet for the screen not as slim or shallow.
EDTV (Extended Definition Television) -- Marketing term for a standard definition TV set that displays a progressive scan (non-interlaced) picture and that usually has horizontal resolution near the high end (over 600 pixels across) for SDTV.
EIA -- Electronic Industries Association, whose members represent equipment manufacturers and establish standards. EIA Resolution -- Video resolution measured in the currently technically correct manner, as TV lines in a distance span equal to the picture height assuming a 4:3 aspect ratio.
Electronic Program Guide -- Feature on some cable TV tuners and other tuners that takes information for the purpose encoded in received program material and displays program schedules, program descriptions, etc. as provided. Interactive Program Guide -- A similar feature with communication back to the source, allowing viewer interaction such as requesting additional information or even selecting a program for video on demand or pay per view.
Electrostatic Loudspeaker -- A loudspeaker consisting of two metal grids (the holes or perforations let the sound out) with a diaphragm consisting of a membrane in between that vibrates in accordance with charges on the grids. It is quite often used for tweeters whereas it would have be quite large (many square feet) to move enough air for low frequency reproduction.
Enhanced Black -- Setting on some DVD players causing the source material official black to white range to be spread out over the the range 1 to 235 rather than the standard 16 to 235 using 8 bits, or over the analog range 0 to 100 (IRE units) rather than the U.S. NTSC standard 7.5 to 100 IRE. This setting is meant to match the DVD player to the TV's characteristics and may or may not bring out shadow detail and may even hide some shadow detail.
Enhanced for 16:9 -- For DVD, refers to a program where the entire 720 by 480 pixel video frame represents a 16:9 aspect ratio image. Whereas for a "standard wide screen" program, only the middle 720 by 360 pixels represent a 16:9 image with the topmost and bottommost pixels are unused (see "letterbox"). To show the full resolution, the enhanced program must be viewed on a TV or monitor with an adjustable image height control or a 16:9 aspect ratio screen. The exact number of pixels of picture height excluding letterbox bars will vary depending on the exact aspect ratio of the image, although the enhanced version will still have better resolution than a standard letterbox edition. All DVD players have a setting to reconstruct the picture with some loss of vertical resolution to be viewed on a standard 4:3 TV set without a height control. Enhanced wide screen programs may also be labeled "anamorphic" or "high resolution".
EP -- Extended Play.
EPG -- Electronic Program Guide
Equalization -- Non-flat frequency response curve or contour built into an amplifier to optimize the audio signal for the recording media or to correct for deficiencies that occur or that have occurred during recording or transmission. Often a record equalization curve and a complementary playback equalization curve to restore overall flat frequency response represent a standard. For example, the RIAA recording equalization attenuates bass frequencies so record grooves will have less excursion permitting groove spacing to be less, and playing time on a record can be greater.
Extended Kell Factor -- See Kell Factor
Extended Play -- (1) The slowest tape speed on a VHS VCR yielding six hours of recording on a "two hour" or "T-120" tape. (2) A 45 RPM phonograph record with ultra fine grooves and more than five minutes of playing time (enough for two typical popular musical selections) on each side.
FALD -- A marketing term for LED and some LCD TV sets, standing for "full array" (q.v.) and "local dimming" (q.v.).
Field -- Either just the odd lines of an interlaced video image, or just the even lines. A field is technically half of the picture.
Field Dominance -- A somewhat artificial but sometimes necessary way of treating pairs of (interlaced) fields as video frames. For (digital) storage of video on disk drives or video disks, it refers to the order in which the odd and even fields are stored .For video editing, when sections or scenes are cut and pasted ("spliced") , every cut must occur before an odd field (F1 dominance) or every cut must occur before an even field.(F2 dominance). The significance of field dominance includes the need to identify the proper temporal sequence for the stored video fields when further processing is done. Simply identifying the video as F2 (even) field dominant does not mean that the odd field in the frame should be located and processed first. There are certain telecine operations where from time to time the even field precedes the matching odd field temporally. Field dominance is not visible in original analog material and properly processed digital video as viewed.
Fill Ratio -- On a fixed pixel display such as an LCD panel, the ratio of the active areas of the pixels to the overall area of the display, which gives a measure of the obtrusiveness of the "gaps between pixels" which gaps show up as a dark grid on the screen.
Filter, Color -- Transparent or translucent layer or film such as cellophane or gelatin ,used to optically block some colors of light and transmit others. (White light is a mixture of many colors.) For TV and video screens and displays the most common colors to be isolated and transmitted are red, green, and blue. Although light is not processed electronically, frequencies in hertz, and wavelengths, are associated with light where red, orange, yellow, green, blue, and violet are in lower frequency to higher frequency order,
Filter, Comb -- See Comb Filter.
Firewire (a.k.a. IEEE 1394) -- One format, used a lot by Apple Computer Corp., for transmitting digital information including video over wire between components such as between a computer and a monitor. Every analog to digital conversion results in some loss of quality, therefore it is advantageous to transmit video digitally to any component (such as a scaler) that processes video digitally. It is not very common in consumer video applications because it currently does not support HDCP copy protection.
First Surface Mirror -- Mirror with the reflective layer on the outer surface, used to avoid ghost images from additional reflections if light has to first pass through the mirror glass and then hit the reflective layer.
5.1 -- Sound system with left, center, and right front channels, left and right rear channels, and subwoofer. 5.0 -- The same system without the subwoofer. See, also, Surround Sound
Flat -- Aka spherical; not requiring processing or reshaping to achieve the desired aspect ratio, on a screen or display device with square pixels.if digital. The opposite of "anamorphic."
Flexplay -- Trademark of a movie rental service issuing disposable DVD's which are sold and which "biodgrade" shortly after the package is opened, allowing a viewing time of about two days.
Flutter -- (1) Repeated rapid increase and decrease of pitch of the reproduced audio, more than about two repetitions per second, due to non-uniform linear speed of analog tape. (A slow repetition is referred to as wow.) (2) Choppy rapid breakup and resynchronizing of a television picture from such causes as over the air signal reflection off of an airplane passing overhead.
Flying Spot Scanner -- See Telecine
Foldover -- (1) Defect where part of the top of the picture is superimposed upside down over the material just below, or a similar effect on the bottom or (less often seen) on a side. Quantitatively it could be something like (each instance may vary) scan line 20 being on top, scan lines 21 and 19 below it, scan lines 22 and 18 next, and on down to scan lines 39 and 1 superimposed. (2) Frequencies above a certain magic number in Hz (Nyquist frequency) showing up as spurious frequencies the same number of Hz below that number in Hz, for example if the magic number was 10000, a 11000 Hz frequency shows up as 9000 Hz, a 12000 frequency shows up as 8000 Hz. This is a defect; content above the magic number should be filtered out prior to processing. In audio, sour notes are produced.
Foley -- Machine used to generate sound effects for movies. The effects are nowadays usually prerecorded or electronically synthesized but originally they were created using mechanical noise making devices such as springs, flapping cards, beaters on wood blocks and cloth, etc. Named after Jack Donovan Foley (1891-1967) who was a pioneer in the art of adding sound effects to movie soundtracks.
Footprint -- (1) Roughly speaking, the physical size and shape of the portion of an object or building, nearest the floor or shelf or ground it is resting on. For a TV set on legs, the footprint would be the shape described by a string that encircled all of the legs. For a VCR with rubber feet but no legs, the footprint would be the shape of the entire body. (2) In an abstract sense, the irreversible consequences of a format or set of rules. For example, the 720 (or 704 depending on subject matter) pixel wide by 480 pixel high "grid" representing the DVD picture is a footprint, which in this context forever constrains the picture data to occupy discrete pixel positions implied by that grid and not occupy the spaces in between. Composite video is also a footprint whose manifestation in a video image is smeared color boundaries and rainbow effects amidst fine details, among other things. Color resolution is highly limited and it is almost impossible to get rid of all of the contamination from each other when the luminance and color information are finally and mandatorily separated for display of the picture.
Foot Lambert -- Measure of illumination level including light output off of video displays. One foot lambert stands for the level of illumination as seen on a uniformly lit panel where the sum total of light reflecting off of or emitted by one square foot of panel or screen area is approximately equal to the sum total of light (about 12-1/2 lumens) given off in all directions by a lit candle. Foot Candle -- Similar to foot lambert except the amount of light emitted or reflected is one lumen per square foot of surface area. See, also, Nit.
4K -- Today (2023) refers to video formats with roughly 4000 pixels across, including UHD, with a 3840 x 2160 pixel frame. The latter is common nowadays in a larger TV set or other consumer video display although 4K and UHD source material is not widely available. (2) Rigorously refers to video formats with 4096 pixels across. The 4K formats were used originally for (digital) shooting and production. Most common resolutionss used here are 4096 x 2160 for an approximately 1.85:1 aspect ratio, and 4096 x 3072 for scanning of approximately 4:3 film frames.
48i -- 48 interlaced fields per second more or less corresponding to 24 frames per second. See, also @60i.
4.1 -- Sound system with left and right front channels, left and right rear channels, and subwoofer. See, also, Surround Sound
4:2:2 -- One method of specifying color (chrominance) resolution of digital video signals. The first number is the reference count of luminance pixels in a block taken from a row or scan line. The second number is the corresponding number of color pixels in the respective blocks within odd rows or scan lines. The third number is the corresponding number of color pixels in the the blocks within even rows. DVD's rating is 4:2:0, the color resolution is half the (advertised; published) luminance resolution both horizontally and vertically, or each two by two block of luminance pixels has to be the same hue, or color in the sense of pink and red being the same color. In practice the color for a block of pixels may or may not be an interpolation such as the average taken from all of the relevant neighboring pixels. For analog video luminance and color resolution vary independently.and the color resolution may vary depending on which colors are juxtaposed, so this method cannot be easily applied. We could say that contemporary NTSC broadcasts have a rating of roughly 4:0.5:0.5 or 8:1:1 (330 lines luminance, 40 lines color) although unlike digital video the "pixels" or the aforementioned blocks on each scan line don't have to line up vertically.
fps -- Frames per second. Also see Segmented Frame which may use the notation "psf". Often "i" (as in 60i, not 480i) is used to stand for fields per second.
FPTV -- Front Projection Television, including both floor standing boxes and ceiling mounted projectors together with a separate usually wall mounted screen, as distinguished from rear projection TV usually as a self contained box with translucent screen.
Frame -- All of the scan lines, both odd and even, that make up one complete "painting" of the video screen. Also any one exposed picture on a strip of movie film. Note that for interlaced video, one "frame" does not necessarily yield a single complete image subject-wise since subject motion may have occurred between capture of the odd field and capture of the even field.
Front Porch -- The few milliseconds of zero signal level at the end of the subject matter on a scan line and at the start of the Horizontal Retrace Interval.
Front Projection -- Video display technology consisting of a unit typically placed in the center of a room (usually near the ceiling) projecting a picture onto a movie screen or other surface. Front projection is used to provide a picture larger than other methods can achieve but requires a dark room for good shadow detail in the picture.
Full Array -- Refers to LED back lighting with LEDs distributed (in rows/columns) over the full surface of the back light panel. It is subjective how many LEDs there are but typically Full Array has been used to describe TV and video screens with many more than the minimum number needed to get an evenly lit back light panel or the number used in early LED back lit screens.
Full 1080 or Full HD -- The screen has 1080 rows of pixels, enough to display all of the scan lines of 1080i HDTV. This does not guarantee that the electronics display each scan line clearly as opposed to blend it with neighbors on occasion due to shortcomings in the processing.
Full Frame or Full Screen -- Refers to a video program presented in the 4:3 aspect ratio whether or not it was originally created with that aspect ratio. If the original program was of a different aspect ratio the video presentation will use either or both of pan-and-scan (q.v.) techniques and soft matte (q.v.) source material without matting. Contrasted with Full as a setting on a wide screen TV set which refers to displaying the entire video frame content in a 16:9 shape, filling the screen.
Full Range Speaker -- A loudspeaker unit with a single voice coil (not woofer and tweeter in the same frame) that can give good reproduction of all types of music although it may be deficient in the lowest and highest one and one half octaves (below about 60 Hz and above about 8000 Hz.
Funhouse Effect -- Objects get wider or narrower or taller or squattier, or go through other geometric shape distortions, as they move across the screen, due to less than perfect "linearity" of circuits and/or "field uniformity" of lenses. The effect is suggestive of images seen in the curved mirrors found at amusement parks, carnivals, or circuses, often in a location called the funhouse. Nowadays one choice of viewing 4:3 aspect ratio programs on some wide screen TV sets is to have the center of the picture nearly correctly proportioned while the left and right sides are stretched out a little.
Gain -- (1) In a receiving antenna, the greater sensitivity to signals (coming from the favored direction if any) compared with a standard which is another antenna with certain characteristics. (2) in a movie screen, the greater amount of light reflected in desired directions (i.e. towards the viewing area) compared with a screen consisting of a surface painted with a certain standard flat white paint. Screen gain is achieved by reducing light reflected in non-favored directions such as upwards or downwards. (3) in an amplifier or amplifier stage, the amount of amplification.
Gamma -- The relationship between the brightness of a spot on the screen and the level of the video signal in volts or digital numeric values. It can be graphed as a curved line. If twice as many electrons are fired at a spot on a CRT screen, that spot does not look twice as bright to the human eye, Therefore for CRT's the gamma graph is not straight, or linear. In practice gamma also varies with the make and model of the TV set or monitor, the nature and quality of the electronics inside, and also the settings of the brightness and contrast controls. Gamma also applies to film where the intensity of light hitting the film results in the appropriate intensity of the color in the finished print or slide. Adjusting gamma is difficult especially considering that most people cannot tell what is correct unless they have a side by side comparison with the live subject, a supposedly correct photograph of the subject, or a TV that is adjusted correctly. Also personal preferences, comparable to preferences in adjusting stereo bass and treble controls, affect the settings. Typical test patterns for adjusting the gamma consist of dark and light patches, some of them using shades of gray, others using halftoning or dithering of black and white dots. The user is told to adjust controls on the monitor until some patches or stripes are distinguishable and others blend into each other. The instructions for using each gamma chart vary. Re-adjusting gamma may also be done to best show fine shading gradations both near black and near white. See, also, Prime Disclaimer.
Generation Loss -- The degradation experienced when a recording or other information or data is copied. It can be zero, nil, for digital material. Optical disks (CD's, etc.) are not immune from generation loss since the laser reading process is not completely error free. Although the data recording provides for error correction processing, once in awhile so many bits are lost that the original data cannot be reconstructed perfectly.
Genlock (trademark?) -- Feature in a video processor that guarantees one interlaced field or progressively scanned frame of video output for each incoming interlaced field or progressively scanned frame of video. This feature reduces temporal judder caused by repeating or dropping of frames done by the processor but requires that the TV (or other display device) be able to stay in sync. with the video processor's output.
Ghosting -- Duplicate (and not quite juxtaposed), copies of subject matter in analog video, often caused by ringing (electronic overshoot and bouncing) in the TV's circuits or by broadcast signals bouncing off a far away object (building, mountain) and coming back to your antenna time delayed.
Graphic Equalizer -- Group of amplifier tone controls each affecting a different range of audio frequencies and usually in the form of side by side vertical sliders arranged so that a curved line imagined to pass through each of the slider handles suggests a graph of the frequency response of the amplifier at the time.
Gray Scale -- A test pattern consisting of shades of gray, in order, starting with black and ending up with white. It may be a continuous sweep or a series of typically half a dozen to two dozen discrete steps. The gray scale step pattern is especially useful in identifying black crush (darkest shades of gray indistinguishable from black) and/or white crush.
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