CAD – Computer Aided Design. The method of using computers to design electrical and mechanical devices. Designing 2D and 3D work using a computer as a tool.

CAV –  Component Analog Video. Component video signals in which an analog voltage or current represents the value of a pixel.

CATV – Community Antenna Television system. Broadcast signals are received by a centrally located antenna and distributed by cable through a region.

CBR – Constant Bit Rate. A recording preference where, regardless of its quality or complexity, the content will be recorded at the same bit rate from beginning to end. The opposite of Variable Bit Rate (VBR), where the bit rate changes up and down according to the amount of data required by the compression algorithm.

cc – Close Captioned. A system which displays the current dialog on screen for deaf or hard-of-hearing viewers. Contrast with subtitles, intertitles.

CCD – Charge-coupled device. A semiconductor image-sensing device, commonly used in video and digital cameras, that converts optical images into electronic signals.  It replaced the pickup tube; a CCD is a solid state imager which converts input light levels into electrical charges, which are once stored and then output in the form of voltage variations. A digital camera records an image on its sensor, a light-sensitive receptor that is the digital equivalent of film. A CCD is a type of sensor. CMOS is another type. See CCD versus CMOS sensors.

CCTV – a system of transmitting video signals from the point of origin to single or multiple points equipped to receive signals.

CCU – Camera control unit.

CD – Compact Disc. A media format used to store and playback music and data. Typical capacity of 700 Megabytes (MB.)

CD-DA: Compact Disc Digital Audio is an audio-only format on CD. Discs are playable on standard compact disc players and software players on a computer.

CD/DVD/BD-R –  R indicates that the CD (Compact Disc), DVD (Digital Versatile Disc), or BD (Blu-Ray Disc) is recordable. A few different format variations exist for recordable discs such as +R and -R. If marked with only an R, the disc is write once, meaning that data cannot be erased once written. There are also formats capable of erasing and re-writing data, indicated by RW for re-writable or RE for recordable erasable. Aside from some prerecorded groove and recording parameter data, recordable discs are nearly blank slates capable of being formatted for digital audio, video, or computer data. An exception is the pre-formatted CD-DA recordable disc.

CD/DVD/BD-ROM – ROM is an abbreviation for Read Only Memory. It is a standard for formatting discs to store any type of computer readable data without regard to a specified structure. They are readable only (hence the name) unless discs are writable (RW) or erasable (RE). 2. (for CD-ROM) Compact disc read-only memory. A compact disc format that can store data other than just standard CD audio. Many programs, sound sample libraries, and graphics are distributed on CD-ROM because each CD can store hundreds of megabytes of information, yet costs about the same to manufacture as a floppy disk, which only stores about 1 megabyte. See ROM.

CE – an acronym for Conformite Europeenne. The certificate or the CE mark is placed on products to signify that they conform to European Union regulations.

CG – Character Generator. 1. A small computer used to generate titles and other text electronically without the use of a camera; a computer used to generate text and sometimes graphics for video titles.  2. Computer graphics. An all-encompassing term that includes everything related to producing digital graphics. 3. images either partially or completely created at a computer workstation. However, in the field of digital video CG-matrices are used to color convert images from the YUV color space (the color space of television signals) to the RGB color space (the color space used on computers) and vice versa.

CGI – Computer Generated Imagery. 1. The use of computer graphics to create or enhance special effects.  2. The application of the field of 3D computer graphics to special effects. CGI is used in films, television programs and commercials, and in printed media. Video games most often use real-time computer graphics (rarely referred to as CGI), but may also include pre-rendered  “cut scenes” and intro movies that would be typical CGI applications. These are referred to as FMV (full motion video).

CIF – Common Interchange Format. 352×288 pixels; often used for H.261 and H.263 video codecs.

CODEC – 1. Compression-Decompression. Highly specialized algorithms that analyze content of the media, using a variety of rules to remove or exclude redundant information within the video or audio material to greatly reduce the size for storage, transmission and playback efficiency. There are many CODECs, each designed for specific purposes. Virtually all digital media used in consumer applications are compressed.  2. an acronym for coder/decoder. An electronic device that converts analog signals, such as video and audio signals, into digital form and compresses them to conserve bandwidth on a transmission path.

CRT – 1. Cathode Ray Tube; the video display tube used in monitors and receivers, radar displays and video computer displays. The CRT is a high-vacuum tube containing an electron gun to produce the images seen on the face of the tube. 2. Video camera viewfinders are equipped with a CRT image display, so you can monitor what you are shooting.  3. 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.  The current of the video signal is used to control electron rays generated by a cathode and directed onto a phosphorescing plane in a vacuumed tube. Wherever the electrons hit the phosphorescing plane they illuminate a dot on the plane in the brightness of the electron ray’s strength. The image dots (i.e. electron rays) are guided by electromagnetic fields from the left to the right and line by line. Thus an image is created on a screen.

CS – composite sync. A video synchronizing signal that contains horizontal and vertical synchronizing information. Often referred to simply as sync.

CTDM – Compressed Time Division Multiplex. A method of processing chrominance signals for recording. When component video signals are recorded, both of the two chrominance signals (R-Y, B-Y) are time compressed to half, multiplexed, and recorded on  a single track one after the other.

CTL – Control signal in the form of regular pulses recorded along a longitudinal track on the videotape. By counting these pulses, it is possible to determine the number of frames, and hence the tape’s running time. Used mainly to adjust the  tracking position of video heads, and to achieve time code continuity in continuous recording.

CU – Close-up. 1. A shot in which the subject is larger than the frame, revealing much detail. The abbreviation is often used in a slug line. 2. Generally, a picture of a subject that fills the frame, usually with the subject looking particularly close to the camera.

CV – Control Voltage. Control Voltages are used by analog synthesizers to control the oscillators, filters, envelopes generators, LFOs and other components. Originating in modular systems where it was necessary to patch these components together, CV jacks can also be found among hard-wired synthesizers where they were used as an early form of external MIDI-like control for connecting them to other analog devices. CV input and/or output jacks may also be labeled OSC In, Keyboard In, VCO in, or Key Volt.

c-mount lens – A lens with a standard one-inch threaded mount assembly that is screwed into the camera body, as opposed to a bayonet or m-mount.

cable – 1. The electrical cords used to interconnect pieces of audio and video equipment.  2. an assembly of more than one conductor (wire).

cache – An amount of memory set aside to help improve media playback performance by allocating space to either RAM or hard disk drive.

Call Sheet – A listing of which actors will be required for which scenes, and when they will be required. Call sheets are created by assistant directors and others.

cameo – A bit part played by a famous actor who would ordinarily not take such a small part. Originally meaning “a small piece of artwork”, the term was borrowed by director Michael Anderson when attempting to attract famous actors to play bit parts in Around the World in 80 Days.

camera – 1. A device for recording images. 2. (3D) Like a real-world camera, the 3D camera frames the view of a scene by tracking, tumbling, panning, and zooming. Unlike a real-world camera, the 3D camera does not automatically capture lighting, motion blur, and other effects – these effects must be explicitly created and tuned for realistic output.

camera cap – A cap screwed or mounted onto the front of a camera in place of the lens to protect the camera pickup tube from light or dirt when the lens is not in place.

camera crew – The group of crew members directly involved with operation of the camera. Individual job titles include: clapper-loader, camera operator, assistant cameraman, director of photography, focus puller, grip, key grip, dolly grip, additional camera.

Camera Loader – Clapper-Loader, Clapper Loader. The person who operates the clapboard at the beginning of a shot, also responsible for loading film stock into film magazines. The action of slapping the clapper was invented as a way of synchronizing the visual and audio components of a shot. Recent innovations in audio-visual synchronization have made this unnecessary, but it still occurs extensively. See also assistant cameraman.

camera log – A record sheet that catalogs details of a scenes photographed on the original film.

Camera Operator – Cameraman. The person who operates the camera to the specifications dictated by the director of photography.  A director or a director of photography sometimes assumes this role. (Luc Besson always operates the camera on films he directs.) See also Steadicam operator.

camera report –  The form used to identify what is on each exposed camera roll and any special printing or transfer instructions.

camera target (interest) – What the camera points at.

camp – also campy.  A form of comedic parody where the clichéd conventions of a dramatic form like adventure are deliberately exaggerated to the point of ridiculousness. Often unfairly used to describe superhero films and shows as Batman is a prime example of this form of comedy.

can – combine effects of panning, tilting, and pedding in one fluid movement.

cannon – A three-pin connector used with balanced audio lines for line and mic level audio signals. Also known as an XL or XLR connector.

capacitance – the ability of a nonconductive material to develop an electrical charge which can distort an electrical signal. A common misunderstanding about electrical capacitance is to assume that capacitance represents the maximum amount of charge a capacitor can store. That is misleading because capacitors don’t store charge (their total charge being zero). They “separate charge” so that their plates have equal and opposite charge. It is also wrong because the maximum charge one may put on a capacitor plate is determined by the potential at which dielectric breakdown occurs. Compare: capacity.

capacitive reactance – the opposition a capacitor offers to alternating current flow. Capacitive reactance decreases with increasing frequency or, for a given frequency; the capacitive reactance decreases with increasing capacitance. The symbol for capacitive reactance is XC.

capacitor – An electrical device which stores energy as an electrostatic charge. Often used as a component in filter circuits. It allows the apparent flow of alternating current while blocking the flow of direct current. The degree to which it allows ac flow depends on the frequency of the signal and the size of the capacitor. Capacitors are used in filters, delay-line components, couplers, frequency selectors, timing elements, voltage transient suppression, etc.  We probably should avoid the phrases “charged capacitor”, “charging a capacitor” and “store charge”. Some have suggested the alternative expression “energizing a capacitor” because the process is one of giving the capacitor electrical potential energy by rearranging charges on it (or within it). Some who agree with most everything I have said on this topic still defend “stored charge”. They say that the capacitor circuit separates charge and then stores equal and opposite charges on the capacitor plates presumably for release by discharge through a circuit (rather than by discharge within the capacitor). That’s a correct description for it puts the capacitor in the context of the circuit to which it is attached. But the abbreviated phrase “The capacitor stores charge” is still misleading and should be avoided unless it is explained as I have done here. And it’s still more to the point to say the capacitor stores electrical potential energy.

capture – Process of feeding media material from outside sources into a computer. When capturing media from an outside source it requires special hardware, the video capture card. Special software is needed too, when capturing video of what is displayed on the computer screen.

capture rate –  A term used to describe the number of times/second that a picture is taken or captured in an imaging system. In a progressive system, the capture rate is equal to the frame-rate. In an interlaced system, the capture rate is double the frame rate. This is due to the fact that at each capture interval only one (1) field (a half resolution image) is acquired. It takes two (2) fields to make a complete frame.

captive screw connector – sometimes called a Phoenix connector, it is a molded plastic connector whose termination requires that you strip and slide a wire directly into a slot on the connector. A set screw then pushes a gate down to hold the wire in place.

card – 1. A plug-in memory device. RAM cards, which require an internal battery, can be used for storing user data, while ROM cards, which have no battery, can only be used for reading the data recorded on them by the manufacturer. 2. A circuit board that plugs into a slot in a computer.

cardboarding – Lack of true 3D feel to a shot making it look like it is made from cardboard cut-outs. This is also referred to as Cut-out Planar Effect. Caused by inadequate depth resolution due to an incorrect matching between the focal length of the recording lens (or CGI camera) and the interocular distance between the cameras. See: Interocular.

cardioid – heart-shaped region where some microphones will be most sensitive to sound predominately from the front of the microphone diaphragm and reject sound coming from the sides and rear.

carrier – 1. modulated frequency that carries video or audio signal. 2. A signal that is being modulated or regulated by some other signal, as in FM synthesis.

carrier leak – refers to a problem in black and white video that originates from a video playback device. The term is sometimes seen in the context of machine maintenance and calibration due to the origin of the artifact. Carrier leak can be recorded into a second-generation video copy, where it becomes part of the video signal. In recording black and white video, the FM process is used to modulate the video signal (~3 Mhz for black and white) for storage on video tape. During the process of playback, the frequency modulated signal is read by the pair of video heads, amplified and demodulated by electronics in the playback machine. If the processing isn’t accurate so that there is an imbalance in the amplification between the signal read from the two playback heads, a textured and banded pattern is superimposed over the video image. This distortion is the result of the modulated carrier leaking into the demodulated video signal that is displayed on the monitor during playback. There are two reasons why this disturbing interference is found in older video formats in particular. First, the relatively simple video devices were often maintained by the users themselves, i.e., by non-technicians, consequently they were not always properly adjusted; and second, in the very oldest formats, modulation often took place in frequency ranges that lie within the baseband bandwidth of the video signal. If the carrier leak is recorded into the image, there is no way to remedy the artifact. If the carrier leak is occurring due to equipment malfunction, the VTR may need to be serviced.

cast – A collective term for the actors appearing in a particular movie.

casting – The process of hiring actors to play the characters in a script, typically done by a Casting Director, but with some input from a Director, Producer, or studio. See also CSA.

casting couch – During the so-called “Golden Age” of Hollwood, it was not uncommon for would-be-stars to grant sexual favors to directors and/or producers in return for a role in films. These favors were usually rumored to be on a couch in the filmmaker’s office. The phrase “Casting Couch” has been popularized, and although the practice has diminished, the term remains in use.

Casting Director – also Extras Casting, Casting Assistant, Casting Associate. The person who auditions and helps to select all of the speaking role actors in film, television shows or plays. The CD must possess a vast knowledge of the actor pool and be able to match a variety of actors with just the right role. Directors and producers rely on the Casting Director to assist them with assembling the perfect cast for their production. Casting Directors are also responsible for serving as the liason between the director, and the actors and their agents. CDs negotiate the deals with agents once the actors have been cast and are also responsible for the contracts and SAG of each actor.

catch capture – Combining your video capture card with deck control so that you define the “in” and “out” points first, then capture only the footage you want.

category 5 (Cat 5) – the designation for 100-ohm unshielded twisted-pair cables and associated connecting hardware whose characteristics are specified for data transmission up to 100 Mb/s. (Part of the EIA/TIA 568A standard.)

category 5e (Cat 5e) – enhanced version of the Cat-5 cable standard that adds specifications for far end crosstalk. (Part of the EIA/TIA 568A standard.)

category 6 (Cat 6) – cable standard for Gigabit Ethernet and other interconnect that is backward compatible with Category 5 cable, Cat-5e and Cat-3. Cat-6 features more stringent specifications for crosstalk and system noise. (Part of the EIA/TIA 568A standard.)

cautics – The light patterns generated on a surface by reflected or refracted light rays. Photon mapping is one implementation of this.

cement splice – Film splice made using a film solvent cement to make the splice virtually seamless.

cel – A hand drawn sheet representing a single animation frame, usualy made of a clear material like cellulose or mylar to allow several layers of composition.

cel animation – A form of animation where hand drawn pictures are transposed on to plastic sheets, each with a different element such as characters and background, and layered on top of each other to create a complete scene. The composition is then photographed and incorporated in the finished film. It was the predominate of form of animation until the rise of computer generated animation in the mid 1990’s.

censorship – Changes required of a movie by some person or body other than the studio or the filmmakers, usually a national or regional film classification board. See also certificate.

certificates – also certificate, ratings. Various countries or regions have film classification boards for reviewing movies and rating their content in terms of its suitability for particular audiences. For many countries, movies are required to be advertised as having a particular “certificate” or “rating”, forewarning audiences of possible “objectionable content”. The nature of this “objectionable content” is determined mainly by contemporary national, social, religious, and political standards. The usual criteria which determine a film’s certificate are violence and sexuality, with “mature” (adult) situations and especially blasphemy and political issues often being considered more important outside the Western world. This is by no means a hard and fast rule; see the Hays Production Code for an example. In some cases, a film classification board exhibits censorship by demanding changes be made to a movie in order to receive a certain rating. As many movies are targetted at a
particular age group, studios must balance the content of their films against the demands of the classification board. Negotiations are common; studios agree to make certain changes to films in order to receive the required rating. The IMDb uses the term “Certificate” as opposed to “Rating” to avoid confusion with “ratings” meaning the opinions of critics. See also: Banned, NC-17, PG, G, XXX.

cent – The smallest conventional unit of pitch deviation. One hundred cents equal one half-step. Cent is used for measuring the disparity of two pitches in an equal-tempered scale.

Centaurus –  the industry standard for high-end, uncompressed video I/O hardware.

center marker – A cross that indicates the center of the image on the viewfinder screen.

change pages – When a script is being edited during production, changes are distributed to actors and the filmmakers on “change pages”, which are usually a different color to the pages of the script.

change-over marks – also change-over, reel change, reel change marks, cigarette burns. Most completed movies consist of more than one reel, and thus for an uninterrupted screening, at least two projectors must be used. Towards the end of a reel, one or more frames may include a small circle in one of the corners. These are signals to the projectionist that the current reel is approaching the end, and he or she should be ready to start the next projector, which should have the next reel prepared for projection. Also, many theaters have switched to a platter system which allows the entire film to be spliced together and put on a large platter. The film is fed through the center of the reel (unwinding from the inside out), then into the projector, and then back onto another platter. This process allows the film to be show back-to-back without having to rewind it.

channel – 1. A digital effects processing path for video. 2.  A particular signal path. 3. A portion of the television broadcast spectrum assigned to a particular broadcasting station. 3. An electrical signal path. In analog audio (such as a mixer), each channel consists of separate wired components. In the digital domain, channels may share wiring, and are kept separate through logical operations. MIDI provides definitions for 16 channels, which transmit not audio signals but digital control signals for triggering synthesizers and other devices.

channel pressure – 1. A type of MIDI control message that is applied equally to all of the notes on a given channel; the opposite of poly pressure, in which each MIDI note has its own pressure value. Also called aftertouch, channel pressure is generated on keyboard instruments by pressing down on a key or keys while holding them down. 2. a MIDI control communication that is bestowed uniformly to every note on a specific channel. See aftertouch, poly pressure. Channel pressure.

character actor – An actor who specializes in playing a particular style of character, often stereotypical, offbeat, or humorous.

characteristic curve – A film exposure plot that shows the relationship between the photographic exposure and the image density produced after the film has been processed.

check print –  First film print used to check color corrections.

checksum – A small set of data computed through an algorithm with the intent of detecting errors in data files or blocks introduced through storage or transfer. The checksum data accompanies or is otherwise associated with the data files or blocks, and is used to help ensure data integrity.

Choreographer – A person who plans and directs dance sequences within a movie.

chorusing – 1. A type of signal processing. In chorusing, a time-delayed or detuned copy of a signal is mixed with the original signal. The mixing process changes the relative strengths and phase relationships of the overtones to create a fatter, more animated sound. The simplest way to achieve chorusing is to detune one synthesizer oscillator from another to produce a slow beating between them. 2. combining a time-delayed and original signal.

chroma – The characteristic of a color which refers to its saturation or intensity. Also the color pattern of the television signal. See my Image Glossary for more on chroma.

chroma key – also chromakey.  1. A key based on the chroma saturation and hue of portions of a picture, rather than on the luminance, or brightness. A specific hue is replaced by one picture source, while the rest of the picture is replaced by another picture source. A chroma key is an external key.                 2. Electronically matting or inserting an image from one camera into the picture produced by another. Also called “keying.” The subject to be inserted is shot against a solid primary color background. Signals from the two sources are merged through a special effects generator.

chroma keying – also chromakeying. 1. Also known as “blue screen” or “green screen”, chroma keying is the process of removing a selected color from an image. For example, to show an actor standing in front of a computer generated background, the footage of the actor can be shot against a green screen. The background can then be removed with the chroma key video effect to reveal another clip underneath which will provide the new background. For best results, the background to be removed must be a very consistent color (e.g., without highlights or shadows), and the background color must not appear on actors or objects which you don’t want to remove. 2. Overlaying one video signal over another is defined as chromakeying. The areas of overlay must be defined by a specific range of color, or chrominance, depending on the foreground signal. The chrominance must have sufficient bandwidth or resolution. Chromakeying is also called blue screen or green screen, depending on the color being replaced. 3. In 3D compositing: The most popular method to automatically pull matte is chroma-keying, where mask is created from the difference between the colour of the object to be masked and the colour of the background. The key to success here is to find the background colour which differs completely from the target, and to light it evenly. When none of the pixels in the background matches the colour of the target pixels a perfect matte is pulled. TV production houses, for example, use systems capable of real-time chroma-keying. Blue screen: A blue background used to chroma key people. It is of a special shade of blue which is not usually present in the colour of the human skin. So often used that blue screen and chroma key today are almost synonymous. Ultimatte: Synonymous to blue screen. Originally the name of the company manufacturing chroma-keying systems.

chrominance – 1. the color portion of a composite or S-Video signal; video picture information contains two components: luminance (brightness and contrast) and chrominance (hue and saturation). 2. The color portion of the television signal, which contains the color information (hue and saturation).

chrominance noise  – can be identified as traces and specks of color in an otherwise clear picture. It is most visible in dark, saturated areas of the video image. It can be due to limitations of CCD sensitivity in video cameras (i.e., low-lighting conditions during camera recording), over-boosting of chrominance in the video signal, or the use of poor video processors.  Multi-generation composite dubs may suffer from high levels of chrominance noise. If the video output has been properly adjusted for playback, there is not an acceptable fix for this problem in preservation workflows.

chrominance signal – Or chroma signal is a video signal containing color information.

chute cowboys – Slang term for experienced parachutists that either perform or assist with stunts involving parachutes.

chyron – Text graphics which appear at the bottom of a screen used to describe time, place, or name of person on screen; can also describe the technology used to add the text to the bottom of the screen.

cinema – A place where screenings occur. Cinemas can be hardtops or ozoners.

Cinema Verité – literally: Cinema Truth. A documentary style in which no directorial control is exerted. The term is frequently misused to describe new-wave “handheld” camera techniques.

Cinematographer –  or Cin. A person with expertise in the art of capturing images either electronically or on film stock through the application of visual recording devices and the selection and arrangement of lighting. The chief cinematographer for a movie is called the director of photography.

cinemascope – A trade mark system of wide screen presentation. The 35mm film image is compressed horizontally by 50% in the negative stage and when the film is printed and projected, the 35mm print image is expanded horizontally by the same amount using an anamorphic projection lens. The screen image has an aspect ratio of 2:35:1.

cineon –  This is a file format that was specifically designed to represent scanned film images.

circuit – The interconnection of a number of devices to perform an electronic function.

clamp, clamping – The circuit or process that restores the dc component of a signal. A video clamp circuit, usually triggered by horizontal synchronizing pulses, re-establishes a fixed dc reference level for the video signal. Some clamp circuits clamp sync tip to a fixed level, and others clamp back porch (blanking) to a fixed level. A major benefit of a clarnp is the removal of low-frequency interference, especially power-line hum.

clangorous – Containing partials that are not part of the natural harmonic series. Clangorous tones often sound bell-like.

clapboard – also Clapper or slate. A small board which holds information identifying a shot. It typically contains the working title of the movie, the names of the director and director of photography, the scene and take numbers, the date, and the time.  It is filmed at the beginning of a take. On the top of the clapboard is a hinged stick which is often “clapped” to provide audio/visual synchronization. See also clapper-loader, continuity report.

Clapper-Loader – See Camera Loader.

claw – Mechanism used is most cameras to advance the film.

Claymation – Animation of models constructed from clay or plasticine.

Clean Speech – A take in which all dialogue was performed without error.

cliffhanger – A moment of high drama, frequently used at the end of serials. Named for the (now cliché) practice of leaving a hero or heroine hanging onto the edge of a cliff.

clip – A term usually in reference to a section of or sometimes even an entire video program.

clock – Any of several types of timing control devices, or the periodic signals that they generate. A sequencer’s internal clock is always set to some number of pulses per quarter-note (ppq), and this setting is one of the main factors that determine how precisely the sequencer can record time-dependent information. The actual clock speed is usually determined by the beats-per-minute setting. See ppq, bpm, MIDI clock.

clock adjustment – also called timing signals, used to fine tune the computer image. This function adjusts the clock frequencies that eliminate the vertical banding (lines) in the image.

clock resolution – The precision (measured in ppq) with which a sequencer can encode time-based information.

coaxial cable – A cable having a center signal carrying conductor surrounded by insulation and a concentric outer conductor grounded metallic noise shield, and optional protective covering, all of circular cross-section. Abbreviated coax. In television, the cable impedance is 75.

coding – Ink stamping or burning numbers into the edges of work print and work track to mark sync points. It is done with a “coding” machine.

coercivity –  Measures the force required to erase a video tape that has been recorded to the maximum possible level. Coercivity is measured in “Oersteds”.

Cold Open – A cold open, or teaser, is a short segment of a TV show’s action, shown before the program’s opening credits are shown. It serves to heighten a viewer’s interest and to build dramatic tension before the show begins.

color analyzer – Equipment used to color correct a negative and to determine the correct printing lights.

color bar signal –  a video test signal which can be displayed as vertical bars of different colors on a color video  monitor. Contains bands of color with fixed amplitudes and saturations. Widely used for system and monitor setup, it is used to check chrominance functions of color television and camera-s.

color burst – that part of an NTSC video signal that carries the color information. It is a signal consisting of several (8 to 10 in NTSC) cycles of unmodulated color subcarriers, superimposed at a specified location within the composite signal.

Color Consultant – A technical advisor with expertise in film stock and film developing, who provides advice for cinematographers and color timers. For more on color, see my Image Glossary; my PhotoList; and Jae Kamel’s JKU One, in the Art Category.

color conversion filter – Is an optical filter used with video cameras to convert the color temperature of a light source.

color correction – The altering of color balance.

color difference signals – signals which convey color information such as hue and saturation in a composite format. Two such signals are needed. These color difference signals are R-Y and B-Y, sometimes referred to as Pr and Pb or Cr and Cb.

color fade – The result of chemical instability in color print stocks that leads to magenta prints.In these cases the yellow and cyan (blue-green) layers have faded, leaving magenta(blue-red) as the only prominent color.

color separation negative – Black and white negative made from red, yellow, or blue light from an original or positive color film.

color temperature – Term that describes the color of light sources; color quality expressed in degrees Kelvin (K).  The temperature at which a ‘blackbody’ emits enough radiant energy to evoke a color equivalent to that coming from a given light source. A high color temperature corresponds to bluer light, a low color temperature to redder light. Each light source has its own color temperature. The color temperature of daylight is around 5500K. See also my Image Glossary for info. about color.

color timing – also color correction, color timer, color corrected. A process which adjusts the final print so that colors match from shot to shot, regardless of the film stock and camera used to shoot the scene. So named because one aspect is adjusting the exposure time of each shot. Performed by a color timer. See also color consultant.

Colorist – An image artist who, during post-production of a movie or television show, utilizes computer-based alteration/correction programs to go through the movie/show frame by frame to insure color and light continuity. The colorist may also tweak colors to stylistically heighten them.

colorization – A film alteration process where an operator digitally alters a black and white image to include color. It is a controversial practice because many filmmakers and viewers believe it fundamentally alters an artistic creation. Early attempts at colorization in the 1980’s were relatively crude in their shading range. Citizen Kane is notable in that Orson Welles was able to legally prevent its alteration.

comb filter – transversal filter that combs out a specific set of frequencies. Comb filters are very effective in separating the chrominance and luminance sidebands in an NTSC video signal.

combiner – in a process called multiplexing, the combiner puts signals together onto one cable constituting a broadband signal.

common-mode – refers to either noise or surge voltage disturbances occurring between the power neutral (white wire) and the grounding conductor (green wire). Unwanted common mode disturbances exist as a result of noise injection into the neutral or grounding wires, wiring faults, or overloaded power circuits.

common mode rejection (CMR) – A measure of how well a differential amplifier rejects a signal which appears simultaneously and in-phase at both input terminals. As a specification, CMR is usually stated as a dB ratio at a given frequency.

common-mode rejection ratio (CMRR) – 1. The ratio of the common-mode interference voltage at the input of a circuit, to the corresponding interference voltage at the output. 2. For a differential amplifier, the ratio of differential gain to common mode gain. Expressed in dB, the ratio of common mode input voltage to output voltage. For an operational amplifier, the ratio of the change in input/offset voltage to the change in common mode voltage.

companding – A type of signal processing in which the signal is compressed on input and expanded back to its original form on output. Digital companding allows a device to achieve a greater apparent dynamic range with fewer bits per sample word. A signal is compacted upon entry and enlarged to its original shape on release.

component – component signal keeps luminance and chrominance separate. It provides better picture quality.

component analog – The unencoded output of a camera, videotape, etc…consisting of three (3) primary color signals, i.e. red, green & blue (RGB), that together convey all necessary picture information.

component digital – A digital representation of a component analog signal set, most often Y, B-Y, R-Y.

component video – color video in which the brightness (luminance) and color hue and saturation (chrominance) are handled independently. The red, green and blue or, more commonly, the Y, R-Y, B-Y signals are encoded onto three wires. Because these signals are independent, processing such as chroma keying is facilitated.

component video signal – A signal that consists of a luminance signal (Y) and two chrominance (color difference) signals (R-Y, B-Y).

composer – A musician whose music appears in a movie’s score. Most movies have at least some original music written for the score, usually after the relevant parts of the movie have been filmed. See also lyrics.

composite –   combines luminance and chrominance. It is usually less expensive than component.

composite analog – An encoded video signal, such as NTSC or PAL video, that includes horizontal & vertical synchronization information.

composite digital – A digitally encoded video signal, such as NTSC or PAL video, that includes horizontal & vertical synchronization information.

composite print – also called Synchronized Print. A print with a images and sound on the same strip of film. The sound component may be either a magnetic soundtrack or an optical soundtrack. See also advance.

composite video – 1. An encoded video signal, such as NTSC or PAL video,that includes horizontal and  vertical synchronizing information. composite video signal 2. A signal that consists of video (luminance and color subcarrier), sync (horizontal and vertical), and color burst signals. 3. Composite video combines all video and synchronization information into one signal. It was developed as a practical way of broadcasting video. It also allowed video to be transferred via a single wire, and was later adopted as a way to record video onto tape. Beginning with Betacam, professional videotape formats successively replaced recording composite video and instead recorded video as separate components. The advantage being increased quality. Consumer videotape formats continued using composite because of the great advantage of directly recording analog broadcasts and the low cost of manufacturing machines. Later as digital broadcasting and data recording proliferated, composite video gave way to component. Below is a list of some of the more common composite videotape formats, including “legacy” formats: VHS, S-VHS, VHS-C, Betamax, Video 2000, Video8, Hi8, U-matic 3/4″, 1/4″ CVC, 1/2″ EIAJ, 1″ Type A, B, and C, 2″ Quadruplex videotape, 2″ Helical Scan (IVC).

composite video signal – the electrical signal that represents complete color picture information and all synchronization signals, including blanking and the deflection synchronization signals to which the color synchronization signal is added in the appropriate time relationship.

compositing – 1. Process of combining separate images into a single new image. 2. The combining of visual elements from separate sources into single images (or sequences of images), often to create the illusion that all those elements are parts of the same scene. Examples might be incorporating rendered 3D images (CGI) into filmed material, or extracting elements shot in front of blue/green screen. Today most compositing is achieved through digital image manipulation.   3. Layering 3D. Creating an image by combining two or more images, often with the aid of mattes to mask off unwanted areas of images. In the film industry, compositing was done on an optical printer, but today it is accomplished almost entirely on a computer. This is largely due to the fact that in digital compositing it is possible to produce successive generations of images (process the same images all over again) without any loss of quality. Compositing is not to be confused with composing, they are not synonymous. 3. Layer. An image carrying information from one specific area of depth in the scene. Compositing is started with the layer furthest off the eye, i.e the background. In an outdoor scene this is often the sky. From there it is proceeded forwards, layer by layer, until the image with the information nearest to the eye (such as the face of an actress) is reached. 4. Plate. Synonymous to layer. The term clean plate refers to the background layer. 5. Matte (mask). An image or a part of an image containing transparency information. The matte is usually a black and white image (1-8 bit) where the white areas are opaque and black areas transparent. This is suitable for compositing, but if it is used to produce transparency on a model in a 3D software, it has to be inverted first. At rendertime, 3D applications automatically generate masks for the objects in the scene. In successful compositing the quality of the matte is crucial.  6. Alpha channel. If matte information is included in a ‘normal’ image it is stored in the alpha channel.  In colour images the alpha channel is the fourth channel after the red green and blue channels.  In black and white images it is the second after the luminance channel.  7. Garbage matte. A matte that needs retouching before it can be used. Methods that pull mattes automatically (such as difference matte) often create garbage.  8. Traveling matte. An approximated, moving matte that isolates an object from the background. Most useful in masking flying objects that never get too close to each other. Often travelling mattes need to be perfected by hand or by combining it with other matte-pulling methods. Then it is a garbage matte.  9. Difference matte. A matte pulled from the differences between two images. For example, to get the mask for a man who walks across the screen we would first shoot the guy walking in front of whatever background, and then, without moving the camera, shoot only the empty background. Computer would then compare the sequences image by image, pixel by pixel, and produce matte only for the pixels that does not match, which, in this case, are the pixels of our man! Because of the slight differences between the backgrounds of the two sequences (produced by film grain or video artefacts, or by differences in lighting if shot outdoors), difference matte is usually a garbage matte.  10. Chroma-keying. The most popular method to automatically pull matte is chroma-keying, where mask is created from the difference between the colour of the object to be masked and the colour of the background. The key to success here is to find the background colour which differs completely from the target, and to light it evenly. When none of the pixels in the background matches the colour of the target pixels a perfect matte is pulled. TV production houses, for example, use systems capable of real-time chroma-keying. 9. Blue screen. A blue background used to chroma key people. It is of a special shade of blue which is not usually present in the color of the human skin. So often used that blue screen and chroma key today are almost synonymous.  11. Ultimatte. Synonymous with blue screen. Originally the name of the company
manufacturing chroma-keying systems.  12. Luma-keying. Like chroma-keying, except that the matte is derived from the differences between the luminance of the background and the object to be masked. Not so versatile, and thus less used, than chroma-keying.  13. Rotoscoping. The last resort: if there is absolutely no other way to extract a mask you can naturally do it by tracing the contours of an object by hand (frame by frame). As well imagined, this is an extremely laborious and time-consuming method.  14. Matte painting. Film special effect: to paint background images for live action scenes. They were  previously hand-painted on glass, but are today created digitally on a paint program.

Compositor – A person who works with compositing. See also digital compositor.

compress –  1.  A digital picture manipulator effect where the picture is made proportionally smaller.  2. The process of converting video & audio data into a more compact form for storage or transmission.

compression – 1. the action of the air molecules moving closer together permitting audible sound. 2. the act of condensing or consolidating material for playback, usually meaning: to change its digital format to allow playback for transmission on non-standard or consumer equipment. 3. Improper video signal level caused by nonlinearity in a circuit’s transfer function. Results in lack of detail in either the black or white areas of the video picture. Can also be caused by pointing a video camera at a scene that has a total black-to-white range. Wider than a standard television signal can handle.  4. Use of a method to reduce the size of digital files or streams of data, also referred to as data reduction. Compression is used to either save data storage space or better enable movement over networks or transmission lines. There are many different techniques to compress data, but all fall into one of two overall categories: Lossless: Any data removed can be reconstructed; and Lossy: Some of the data removed is discarded and gone forever. 5. The process of reducing the amplitude range of an audio signal by reducing the peaks and bringing up the low levels; compression reduces an audio signal’s amplitude range by lowering the high levels and elevating the low ones.  6. The process of reducing a data file in size, often by noting patterns in the data and summarizing them. Some types of audio data compression are “lossy,” meaning the quality of the audio is reduced. See also my Image Glossary for more about compression.

compression ratio – A value that indicates by what factor an image file has been reduced after compression. The higher the ratio, the greater the compression.

compressor – a compressor controls the overall amplitude of a signal by reducing that part of the signal which exceeds an adjustable level (threshold) set by the user. When the signal exceeds the threshold level, the overall amplitude is reduced by a ratio, also usually adjustable by the user.

condensation – is moisture condensation usualy on the head drum, which cases the tape to stick to the drum, resulting in damaging the tape and posible malfunction of the recorder.

condenser microphones – 1. also called a capacitor microphone, it transduces sound into electricity using an electrostatic condenser. 2. A microphone using a power supply (usually a battery) to maintain a charge across two plates which modulate a voltage when the distance between them changes.

conductor – 1. in electronics, a material that easily conducts an electric current because some electrons in the material are free to move.  2. A person who directs the orchestra’s performance of the score, often the composer.

cone – most commonly used component in a loudspeaker system and found in all ranges of drivers.

conferencing systems – the technology by which people separated by distance come together to share information. Conferencing systems may include projection, monitor displays, computers, satellite connections video and audio playback devices, and much more.

conform – Match the original element to the final edited version. (cf. accuracy)

conforming –  To prepare a complete version of your project for viewing or playing out by conforming it. The conformed version might either be an intermediate working version or the final cut.

constraint – In 3D animation: An object or part of an object can be constrained to another object or the world coordinates in order to keep it still. For example, to animate a waving flag, you may first create the wave effect on the flag and then constrain the other end of it to the flag pole. If the constraint source is animated, the constrained object will follow.

Construction Co-ordinator – also Construction Foreman, Construction Manager. Financial responsibilities include budgeting, tracking costs, generating reports, etc. Through drawings, a construction co-ordinator is directed artistically by the Production Designer and Art Director to produce their “vision” in three dimensions. Also responsible for the physical integrity of the structures built by the construction department.

contact print – Print made where the original negative comes in direct contact with the print film emulsion to emulsion.

container – A type of file, also called a wrapper or envelope, which can hold different CODECs according to the design of the  container. AVI, FLV, MKV, MP4, QuickTime, RM and WMV are examples of containers used for multimedia players.

continuity – 1. the quality of being continuous (as in a continuous electrical circuit).  2. The degree to which a movie is self-consistent. For example, a scene where an actor is wearing a hat when seen from one camera angle and not from another would lack continuity. A person is often employed to check that continuity is maintained since re-shooting embarrassing lapses in continuity can be prohibitively expensive. See also continuity report. In modern times, some continuity errors can be corrected through digital compositing.

continuity report – also continuity script. A detailed list of the events that occured during the filming of a scene. Typically recorded are production and crew identification, camera settings, environmental conditions, the status of each take, and exact details of the action that occurs. By recording all possible sources of variation, the report helps cut down continuity error between shots or even during reshooting.

continuous controller – A type of MIDI channel message that allows control changes to be made in notes that are currently sounding. See controller.

contrast – The difference in illumination between the brightest and darkest parts of a scene or picture.

contrast control – A control used to change the amplitude of the video signal in viewfinders receivers, and monitors, but not affecting the output of cameras or other video sources.

control strip – A short piece of film containing a series of film exposures used for checking film processing.

control track – 1. A reference signal recorded on videotape and used to control the path of the video heads across the tape on playback.  2. the portion along a length of a recorded tape on which sync control information is placed; used to control the recording and playback of the signal.

controller – 1.  Any device — for example, a keyboard, wind synth controller, or pitch-bend lever —  capable of producing a change in some aspect of a sound by altering the action of some other device.  2. Any of the defined MIDI data types used for controlling the ongoing quality of a sustaining tone. Strictly speaking, MIDI continuous controllers are numbered from 0 to 122; in many synthesizers, the controller data category is more loosely defined to include pitch-bend and aftertouch data.

convergence –  1. In human eyesight, the ability of our eyes to divert eye optical axes horizontally in an inward direction. The convergence ‘near point’ is the closest point which is still possible to perceive one image. In practice, the eyes can easily converge inward but have much less ability to diverge outward, as it is something we don’t do in life and only when looking at 3D images that have positive parallax beyond the individual human interocular.  2.  In cameras — ‘toeing’ of the cameras (to simulate the eyes converging)focusing on a depth point in the scene, either in front of, behind or at the point of interest. The ‘convergence point’ is where the axes of toed in cameras align on the Z-axis. Convergence can be adjusted in Post by horizontal movement. Note that sometimes the term ‘vergence’ is used to describe both convergence and divergence. Convergence pullers are camera-crew members on a Stereoscopic shoot who are responsible for setting up and shifting the convergence during a shot. See: Parallax.

converter – A software program of changing one media format to another for use in different devices. Often used to take a media format that plays on a computer and transfer it to one that will play on a smart phone, tablet or other mobile device.

convex hull – The “skin” created by enclosing all the extreme points of a 3D object.

Co-Producer – A producer who performs a substantial portion of a creative producing function, or who is primarily responsible for one or more managerial producing functions. A co-producer has less responsibility than a producer for the completion of a project. Note that if a project has more than one producer, it doesn’t mean that these individuals are “co-producers” in the technical sense of that term. See also executive producer, associate producer, line producer.

coupling – The manner in which two circuits or systems are connected. Usually this involves either ac or dc coupling.

Cowboy Shot – A shot framed from mid-thigh up. Got its name during the filming of many westerns, when this was a common framing used.

Crane Shot – A shot taken by a camera on a crane; often used to show the actors/action from above. Cranes usually carry both the camera and a camera operator, but some can be operated by remote control.

creases – A fold or crack in a piece of film.

Creative Consultant – A multi-faceted individual that works primarily for the director of a feature, who helps with the creative process of a film in more than one field (e.g. script, special effects, photography sound design, music, etc.) In many cases, creative consultants go unaccredited, like ghost writers, for various reasons.

Creator – also Concept. The writer or other primary creative force behind a movie, series, or group of characters.

credits – Listings of all those involved in making a program, usually appearing at the end of a television program or film.

cropping –  A rectangular cutting off of image edges. By cropping you remove a part of your image, for example, to receive a letterbox effect (black borders at the top and bottom). As opposed to zoom and pan where you can create a similar effect, the remaining image is normally not scaled back to the size of the video format but remains in its original size.

cross abrasions – Short scratches occurring across the film width. Usually caused during film shipment.

crosscut – The technique of interweaving pieces of two or more scenes, usually in order to show simultaneous actions or illuminate themes.

crossfade looping – 1. a section of data at the start of a loop combines with data at the loop’s end resulting in an even changeover.  2. A sample-editing feature found in many samplers and most sample-editing software, in which some portion of the data at the beginning of a loop is mixed with some portion of the data at the end of the same loop, so as to produce a smoother transition between the end and the beginning when the loop plays.

crosspoint – An electronic switch, usually part of an array of switches, that allows video or audio to pass when the switch is closed.

cross-stitching – in a synthesizer two sounds are set at opposing velocities.

cross-switching – A velocity threshold effect in a synthesizer in which one sound is triggered at low velocities and another at high velocities, with an abrupt transition between the two. If the transition is smooth rather than abrupt, the effect is called crossfading rather than cross-switching. Cross-switching can also be initiated from a footswitch, LFO, or some other controller. Also called velocity switching.

crosstalk – 1. any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel; undesired transmission of signals from one circuit into another circuit in the same system; usually caused by unintentional capacitive (ac) coupling.  2. Signal interference from one part of a videotape to another.

curl – Physical curl across the width of the film.

current – the amount of electrical energy that is flowing in a circuit.current;  the amount of electrical energy that is flowing in a circuit.

curtains – Non-uniform densities running lengthwise of the image.

cut –  1. A change in either camera angle or placement, location, or time.  2. “Cut” is called during filming to indicate that the current take is over. See also shot, action.  3. A “cut” of a movie is a complete edited version.  4.  Instant change between two sources of video, also called ‘hard cut’. However, you can also create cuts or ‘cutting points’ by simply dividing a video clip at a certain position.

Cut List – A cut list is usually provided as a file and used to determine a sequence of video and audio clips. It describes a timeline with video and audio clips via time-code data of succeeding in- and outpoints. Cut lists may also contain information about transitions between clips (hard cut or wipe) and exist in various different, not standardized formats. See also EDL and Timeline.

curvature of field – a blurry appearance around the edge of an otherwise in-focus object (or the reverse) when the velocity of light going through the lens is different at the edges than at the center of the surface, due to the lens design.

curve – The characteristic curve represents the reproduction accuracy in the full tonal scale of the original film. Also know as the H&D Curve developed by Hurter and Driffield.

cutoff frequency – the place within the frequency spectrum past which a synthesizer’s filter lowers the signal being transmitted; the point in the frequency spectrum beyond which a synthesizer’s filter attenuates the audio signal being sent through it.

Cyberpunk – 1. A subgenre of science fiction that typically has elements which include a futuristic tone, massive urban areas in decay and poverty, partial environmental collapse, extremely powerful business corporations, random street gang violence with the overall presence of extremely powerful computer, robotic and information technology. Blade Runner is considered a definitive cyberpunk movie.  2. orig. by SF writer Bruce Bethke and/or editor Gardner Dozois. A subgenre of SF launched in 1982 by William Gibson’s epoch-making novel “Neuromancer” (though its roots go back through Vernor Vinge’s “True Names” to John Brunner’s 1975 novel “The Shockwave Rider”.  Gibson’s near-total ignorance of computers and the present-day hacker culture enabled him to speculate about the role of computers and hackers in the future in ways hackers have since found both irritatingly naive and tremendously stimulating. Gibson’s work was widely imitated, in particular by the short-lived but innovative “Max Headroom” TV series. Since 1990 or so, popular culture has included a movement or fashion trend that calls itself `cyberpunk’, associated especially with the rave/techno subculture.  Hackers have mixed feelings about this. On the one hand, self-described cyberpunks too often seem to be shallow trendoids in black leather who have substituted enthusiastic blathering about technology for actually learning and doing it.  Attitude is no substitute for competence. On the other hand, at least cyberpunks are excited about the right things and properly respectful of hacking talent in those who have it. The general consensus is to tolerate them politely.

cyberspace – 1. encompasses the realm of large electronic networks, it is the national information-space.'
2. Notional
information-space’ loaded with visual cues and navigable with brain-computer interfaces called cyberspace decks'; a characteristic prop of cyberpunk SF.  At the time of this writing (mid-1991), serious efforts to construct {virtual reality} interfaces modeled explicitly on Gibsonian cyberspace are already under way, using more conventional devices such as glove sensors and binocular TV headsets.  Few hackers are prepared to deny outright the possibility of a cyberspace someday evolving out of the network.
3. Occasionally, the metaphoric location of the mind of a person in 'hack mode'. Some hackers report strong eidetic imagery when in hack mode; interestingly, independent reports from multiple sources suggest that there are common features to the imagery.  In particular, the dominant colors of this subjective
cyberspace’ are often gray and silver, and the imagery often involves constellations of marching dots, elaborate shifting patterns of lines and angles, or moiré patterns.

cynch marks – also cinch marks. 1. Short scratches on the surface of the film running parallel to its length. These scratches are caused by film debris or other abrasive particles between film wraps or loose winding.
2. Scratches on a print running parallel to the edge of the strip of film. Typically caused by improper reel winding which allows one coil of the print to slide against another.