Glossary

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3:2 Pulldown: The technique used to convert 24 frames per second film to 30 frames per second video. Every other film frame is held for 3 video fields, resulting in a sequence of 3 fields, 2 fields, 3 fields, 2 fields, etc.
Address Track: A magnetic recording track dedicated to the recording of time code or other numerical data.
Afterglow: A faint image on a cathode ray tube that persists after the passage of the scanning beam. Uncorrected afterglow in a flying spot scanner telecine produces an undesirable flare following light-to-dark transitions.
Airline Version: A film edited to airline industry standards for presentation aboard commercial aircraft.
Amplitude: The magnitude of an electrical signal. Amplitude is usually expressed in standardized units such as volts, millivolts, decibels, or IRE units.
Analog-to-digital converter (ADC, A/D, A-to-D): A circuit that uses digital sampling to convert an analog signal into a digital representation of that signal.
AES/EBU: Informal name for a digital audio standard established jointly by the AES and EBU organizations. The sampling frequencies for this standard varies depending on the format being used; the sampling frequency for D1 and D2 audio tracks is 48 kHz.
Aliasing: Distortion in the video signal which may manifest itself in different ways, depending on the type of aliasing:
Analog Video: A video signal composed of a continuously varying electrical voltage.
Anamorphic: A photographic system that optically compresses the image horizontally during photography and then returns it to normal proportions during projection. Anamorphic photography is used to produce wide-screen images without the use of special wide-format film stock.
Artifact: An undesirable element in the video signal that was not present in the physical object when it was photographed. Artifacts are created by errors in video-signal processing.
Aspect Ratio: The ratio of the image's width to its height. An aspect ratio may be expressed in units of width and height (4:3) or as a mathematical ratio such as 1.33:1 (4 divided by 3).
Assemble edit (assemble mode): A video or electronic edit in which new material is added to the end of existing material on a previously unrecorded portion of the tape. This method replaces all signals on the record tape (video, audio, control, and time code tracks) with new signals.
Best Light: A telecine transfer performed with optimum settings of the color-grade controls, but without precise scene-by-scene color correction. Best light is an intermediate level of transfer quality between one light (single correction setting for an entire reel) and scene-by-scene transfer (programmed color corrections for each shot in the reel).
Beta: Informal name for Betacam, a professional color difference videotape recording format that uses the Y, R-Y, and B-Y color difference components. Also the name of a consumer videotape recording format that is completely different from the professional Betacam format.
Betacam: Portable camera/recorder system using 1/2-inch tape originally developed by Sony. The name may also refer just to the recorder or the interconnect format; Betacam uses a version of the Y, R-Y, B-Y color difference signal set. Betacam is a registered trademark of the Sony Corporation.
Betacam SP: A superior performance version of Betacam. SP uses metal particle tape and a wider bandwidth recording system.
Black and Code: Video black, time code, and control track that are prerecorded on a piece of videotape stock. Black and coded tapes are required for electronic editing in the insert mode.
Blue Screen: Special effects photography in which a subject is photographed in front of a uniformly illuminated blue or green screen. During the effects process, the color screen is optically or electronically eliminated, and a new background is substituted in its place.
Burned-In Time Code: A picture with a visible time code permanently superimposed (burned in), usually in the form of white numbers in a black rectangle. Video recordings with burned-in time code are normally used during previewing and off-line editing to locate the exact time code number of desired shots.
Cathode ray tube (CRT): A tube, usually glass, which is narrow at one end and widens at the other to create a surface onto which pictures can be projected. The narrow end contains circuits to generate and focus an electron beam on the luminescent screen at the other end. Used to display pictures in TV receivers, video monitors, oscilloscopes, computers, etc.
Center Crop: A method of converting film images in a wide-screen aspect ratio such as 1.85:1 to a non-wide-screen ratio such as 1.33:1 by simply scanning or printing only to the center part of the wide-format picture.
Channel
Character generator (CG): A computer used to generate text and sometimes graphics for video titles.
Chrominance: That portion of the video signal which contains the color information (hue and saturation). Video picture information contains two components: luminance (brightness and contrast) and chrominance (hue and saturation).
Clipped Whites: Luminance signal peaks that have been limited in amplitude to prevent their exceeding video system limits. The clipped portion contains no detail information.
Coaxial cable: A cable which has a metallic noise shield surrounding a signal-carrying conductor. In television, the cable impedance is 75 ohms.
Color bars: A video test signal widely used for system and monitor setup. Contains bands of color with fixed amplitudes and saturations.
Colorist: A person who operates a telecine transfer device and its associated equipment, including color correctors, telecine machine controllers, and sound equipment.
Color Timing: The process of selecting color and density values for a film prior to film printing.
Component Video: Color video consisting of separate signals, usually primaries (such as red, green, and blue) or luminance and color difference signals (such as Y, R-Y, and B-Y). In component video systems, these signals are maintained and processed separately.
Composite Sound Track: A sound track containing all required sound elements -- usually dialogue, music, and effects mixed in correct proportions.
Composite video: Video consisting of luminance, chrominance, and synchronizing information encoded into a single signal.
Crosstalk: An unwanted exchange of signals between tracks on a magnetic recording -- for example, leakage of the sound effects track into a dialogue track.
Crushed Blacks: Reduction in the detail of a film or video signal caused by compressing the lower end of the contrast range.
D1: A component digital videotape recording format that conforms to the specifications set in the CCIR 601 standard.
D2: An 8-bit composite digital videotape recording format in which the composite video signal is digitized by sampling it at the rate of four times the frequency of sub carrier (4fsc). The 4fsc frequency in NTSC is 14.3 MHz and 17.7 MHz in PAL.
D3: An unofficial term for a composite digital videotape recording format invented by Panasonic.
D/A converter (digital to analog): A device that converts digital signals to analog signals.
DAT: See Digital Audiotape.
Data compression: A technique that provides for the transmission or storage, without noticeable information loss, of few data bits than were originally used when the data was created.
dB (decibel): A measure of voltage, current, or power gain equal to l/10 of a Bel. Given by the equations 20 log Vout/Vin, 20 log Iout/In, or 10 log Pout/Pin.
Digital: Circuitry in which data carrying signals are restricted to either of two voltage levels, corresponding to logic 1 or 0. A circuit which has two stable states: high or low, on or off.
Digital Audiotape: A digital audio recording format. DAT audio recorders use a 3.8mm-wide magnetic tape that is contained in a plastic cassette; they have 2 channels of audio and allow address track timecode.
Distortion: An alteration of a signal that changes its appearance, sound, or data-carrying characteristics.
Domestic Version: A film or videotape program prepared for distribution in its country of origin.
Drop Frame Time Code: A SMPTE time code format that counts at a rate of 30 frames per second but omits, or "drops," two frame numbers each minute, except for each 10th minute, in order to maintain coincidence of 59.95-fps NTSC video with 60.00 cycle per second real clock time. A total of 108 frame numbers are dropped every 60 minutes.
Dub: A copy of a magnetic recording.
EBU Time Code: A frame-numbering system specified by the European Broadcasting Union that counts at a rate of 25 fps to match the frame rate of the 625/50 PAL system. The system operates in an hours:minutes:seconds:frames format.
Edit Decision List (EDL): A list of data produced by computerized editing systems that describes exactly how the edited master is to be assembled from the source reels. This data can include such information as reel identification numbers, transition codes, and time code locations.
Element: A film, sound recording, or videotape that is part of the overall process of producing a complete presentation.
First generation: The first copy of a videotape. A copy of that copy is termed second generation.
Flutter: Variations in audio pitch caused by rapid changes in the speed of a sound tape or film.
Foreign Version: A film or videotape program prepared for distribution outside the country of origin. Foreign version normally have the original dialogue replaced with dialogue dubbed into the language of the destination country and then mixed with the original music and effects sound tracks.
Formatting: 1. Transfer and editing of material to form a complete program, including titles, credits, logos, and space for commercial and act breaks. 2. Recording of video black, test signals, identification slates, and countdown leader at the head of a videotape reel immediately before a telecine transfer.
Fps: Frames per second.
Frame: A single film or video image.
Frame Rate Conversion: The process of converting material originating at one frame rate to a different frame rate; for example, 24 fps film to 30 fps video.
Full Frame Version: A transfer in which the film image completely fills the entire video screen.
Fx: Effects.
Gain: Any increase or decrease in strength of an electrical signal.
Gate: The area of a film transport where the currently active portion of the film is positioned for scanning or projection.
Hard Record: Immediate recording of all audio and video tracks on a magnetic recorder. A hard record is performed on blank tape when an edit is not required.
Head: The beginning or front of a roll of film or magnetic tape.
Hertz: The unit of measurement for the number of complete cycles of a signal per second. 1 Hertz = 1 cycle per second.
Hi-Fi Audio: Superior quality audio recording. Hi-fi usually refers to FM audio tracks on videocassette recorders.
Insert Edit: An electronic edit in which new audio and/or video information is recorded over existing material or over a previously prepared "base" of video black and control track.
In Time: The film footage or time code number at which an edit or other event is to begin.
Jitter: An unintended variation of a picture's vertical position. Jitter often takes the form of small, random vertical movements of the film in the gate.
Keykode: A proprietary film-marking system developed by Eastman Kodak that applies optical information identifying the film stock and footage to the edge of the film during manufacture. Keykode consists of both "human-readable" numbers and a machine-readable bar code.
Leader: A length of film or tape at the beginning of a reel that facilitates threading and cueing. Leader may also contain identification information and test signals.
Letterbox: An image format in which a wide-screen film is transferred by filling the video frame area with the entire width of the film frame and masking any surplus image showing above and below.
Longitudinal Track: A magnetic recording track that is parallel to the edge of the recording tape or film and therefore runs the length of the reel.
Luminance: The measure of the intensity of the noncolor portion of the video signal; the brightness.
Magnetic Film: Film stock with a coating of magnetic sound-recording media in place of the photographic emulsion.
Mark In: To select a footage or time code location where a specific action, such as an edit, is to begin.
Mark Out: To select a footage or time code location where a specific action is to end.
Mask: A physical device that completely obscures unwanted picture information and defines the intended picture area.
Matte Version: A film print or telecine transfer in which a black matte has been used to limit the viewable image to a specific aspect ratio.
MOS: Without sound; silent.
Music and Effects (M&E): A single sound track containing music and sound effects but not dialogue.
Noise: Unwanted disturbance within an electronic system. Interference present in a video picture.
Non-Drop Frame Time Code: A SMPTE time code format that counts at a rate of 30 fps and numbers video frames in an hours:minutes:seconds:frames format. Unlike drop frame time code, NDFTC eventually drifts out of sync with real time.
NTSC (National Television Systems Committee): Organization that formulated standards for the NTSC television system. Now describes the American system of color telecasting which is used mainly in North America, Japan, and parts of South America. NTSC employs 525 lines per frame and 59.94 fields per second.
Off-line Editing: Editing that is done using inexpensive, non-broadcast-quality equipment to produce an Edit Decision List (EDL) which will be used later for assembling a broadcast quality program using more expensive, high quality equipment.
On-line Editing: Electronic editing performed in a fully equipped edit suite using the original master tapes to produce a final edited master tape that is ready for broadcast or distribution.
Out Time: The time code number that indicates the end of an edit or other event.
PAL (phase alternate line): A video operating standard developed for television broadcasting in much of Europe and other parts of the world. Although there are several variations, the PAL system generally operates on a standard of 625 lines per frame and 25 frames per second.
Pan and Scan: A technique for converting wide-screen films to the 4:3 video aspect ratio. The technique uses the full height of the film image but selectively locates (pans) the available scanning width to include that portion of the film frame subjectively judged to be most essential. The remaining portion of the film's frame is excluded.
Pixel: The smallest distinguishable and resolvable area in a video image. A single point on the screen. In digital video, a single sample of the picture. Derived from the words picture element.
Post production: The editing process after the video footage has been shot.
Preroll: A specific amount of time allowed for tape machines to run prior to an edit in order to get them up to speed and synchronized for the edit. In preparation for the edit, tapes are cued to a point ahead of the edit point to provide a proper preroll. The amount of preroll required varies with each type of VTR.
Pseudo Time Code: Time code derived from a reference signal or mechanical timer pulses when no time code was recorded on the tape or film during production. Although pseudo time code is accurate, it bears no permanent relationship to the film or sound track, and it cannot be recreated once the film or tape is removed from the transport at the conclusion of the transfer.
Quality Control (QC): The examination of a film, video, or audio program or recording to discover its flaws.
Rack: An equipment rack. In video, a standard equipment rack is 19 inches (48.26 cm) wide at the front. Most video equipment is designed to fit into a standard rack.
Reference Tone: An audio signal of constant frequency and amplitude that is recorded at the beginning of an audio- or videotape. The reference tone serves as a guide for setting the correct audio level when the tape is later reproduced.
Resolution: The capacity of a photographic system to record and display image detail.
RGB (red, green, & blue, GRB): The three primary colors used in video processing, often referring to the three unencoded outputs of a color camera or VTR.
Safe Action Area: The central area of a video image that is generally safe from cropping on incorrectly adjusted video monitors or television receivers. The safe action area represents about 90 percent of the total picture area.
Safe Title Area: An area, slightly smaller than the safe action area, that is generally considered safe for the placement of title text.
Satellite
Satellite downlink: The communications path from a satellite to its ground station.
Satellite uplink: The communications path from a ground station to its satellite.
Scan: One sweep of the target area in a camera tube or of the screen in a picture tube.
SECAM: Sequential couleur avec memoire (sequential color with memory). A color television system with 625 lines per frame and 50 fields per second, developed by France and the USSR. Color difference information is transmitted sequentially on alternate lines as an FM signal.
Signal generator: A test oscillator that can be adjusted to provide a test signal at some desired frequency, voltage, modulation, and waveform.
Slate: An identification board that is briefly held up in front of the camera at the beginning of a take to display information about the take. Also refers to electronic slates generated at the head of a program to display information such as its title, runtime, and date of creation.
SMPTE (Society of Motion Picture and Television Engineers): A professional organization that sets standards for American television.
SMPTE time code: Time code that conforms to SMPTE standards. It consists of an eight-digit number specifying hours:minutes:seconds:frames. Each number identifies one frame on a videotape. SMPTE time code may be of either the drop-frame or non-drop frame type. In GVG editors, the SMPTE time code mode enables the editor to read either drop-frame or non-drop frame code from tape and perform calculations for either type (also called mixed time code).
Standards Conversion: The process of converting video created in one line standard, such as 525/60 NTSC, to another, such as 625/50 PAL.
Stock: Unexposed film or unrecorded audio- or videotape.
Striped Stock: Videotape stock that has been prerecorded with video black and time code.
Tail: The end of a reel of tape or a roll of film.
Telecine: A device that converts motion picture film images into video.
Textless Material: The background images of any portion of film or television program over which titles or other text were placed in the "texted" version.
Time-base corrector: Device used to correct for time base errors and stabilize the timing of the video output from a tape machine.
Time code: Timing code laid down on videotape to give each frame a unique number so as to ensure exact transitions during editing.
Time Code Window: A rectangle containing a visible display of time code numbers that is superimposed over a video image.
Time-of-Day Time Code: Time code that approximately matches the actual time of day (clock time).
Tone: Typically refers to a single-frequency audio signal used as a level setting reference.
Uplink: The earth station that transmits signals to a satellite for relay to another location on the ground.
Vertical Interval Time Code (VITC): Time code information that has been converted to narrow video pulses and inserted on a pair of video lines in the vertical synchronizing interval. Unlike longitudinal time code, VITC can be read when the videotape recorder is in the stop or still mode.
Weave: The undesired lateral movement of a film in a camera or telecine.
Wild Track: A sound recording made without accompanying picture.
Window Dub: A videotape copy made with time code numbers permanently superimposed over a portion of the picture. Window dubs are used for off-line editing and shot selection.