0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 
Name Description
16x9 A wide screen television format in which the aspect ratio of the screen is 16 units wide by 9 high as opposed to the 4x3 of normal TV.
24-bit color Color for which each red, green, and blue component stores 8 bits of information. 24-bit color is capable of representing over one million different variations of color.
2:3 pulldown  See pulldown. 
2K An image scanned into a computer file at a resolution of 2048 horizontal pixels.
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, 2 fields, etc. 
4 fsc Composite Digital video as used in D2 and D3 VTRs. Stands for 4 times the Frequency of Subcarrier, which is the sampling rate used.
4:2:2 The sampling ratio used in the D1 (CCIR 601) digital video signal. For every 4 samples of luminance there are 2 samples each of R-Y (Red minus Luminance) and B-Y (Blue minus luminance).
4:3 The aspect ratio of conventional video, television, and computer screens.
4:4:4 A sampling ratio that has equal amounts of the luminance and both chrominance channels.
4K An image scanned into a computer file at a resolution of 4096 pixels. 4 K is considered to be a full-resolution scan of 35mm film.
8mm A compact videocassette format that uses magnetic tape and is eight millimeters wide. 8mm is a world-wide standard and offers high-quality recording and playback of video and audio. 
A and B cutting A method of assembling original material in two separate rolls, allowing optical effects to be made by double printing ( A and B Printing).
a-frame edit A video edit which starts on the first frame of the 5 video frame (4 film frame) sequence created when 24 frame film is transferred to 30 frame video (see 3:2 pulldown). The A-frame is the only frame in the sequence where a film frame is completely reproduced on one complete video frame. Here is the full sequence (The letters correspond to film frames.) A-frame=video fields 1&2, B-frame= video fields 1&2&1, C-frame=video fields 2&1, D-frame=video fields 2&1&2.
A-mode  A linear method of assembling edited footage. In A-mode, the editing system performs edits in the order in which they will appear on the master, stopping whenever the edit decision list (EDL) calls for a tape that is not presently in the deck. See also B-mode, C-mode, D-mode, E-mode, source mode. 
a-mode edit An editing method where the footage is assembled in the final scene order. Scene 1, scene 2, ...
A-roll  A method of conforming that requires the compositing of all multilayer effects into a single layer (including laboratory-standard dissolves and fades) before assembly. Also called single-strand editing. 
A-to-D converter An electronic device that converts analog signals to digital. An A-to-D converter is an integral part of digital-video-related technology.
A/B roll Typically, A/B roll is an editing technique where scenes or sounds on two source reels (called roll A and roll B) are played simultaneously to create dissolves, wipes, and other effects. On nonlinear editing systems, A/B roll refers to using two source streams (.avi, .wav, .tga, and so on) to create an effect.
A/B-roll linear editing Recording edits from two video sources, such as two VCRs to a third, to achieve transition effects. See also, B-roll
A/D converter  Analog-to-digital converter. A device that transforms a continuously variable (analog) signal to discrete binary bits that represent digital samples of the original signal. 
A/V drive Audio/video drive; a high-end hard drive capable of storing high-bandwidth (i.e., high data rate) audio/video data. 
AC'97, AC'98 These are definitions by Intel for the audio I/O implementation for PCs. Two chips are defined: an analog audio I/O chip and a digital controller chip. The digital chip will eventually be replaced by a software solution. The goal is to increase the audio performance of PCs and lower cost. 
AC Coupled AC coupling passes a signal through a capacitor to remove any DC offset, or the overall voltage level that the video signal "rides" on. One way to find the signal is to remove the DC offset by AC coupling, and then do DC restoration to add a known DC offset (one that we selected). Another reason AC coupling is important is that it can remove large (and harmful) DC offsets. 
academy  Pertaining to specifications that meet the Academy of Motion Picture Arts and Sciences standards, such as academy leader, academy format (for film stock), academy countdown, and so forth. 
access time The length of time it takes to find, retrieve, and display digital information.
active picture area The part of a TV picture that contains actual picture as opposed to sync or other data. Vertically the active picture areas is 487 lines for NTSC and 576 lines for PAL. The inactive areas is called blanking.
ADC, A/D Analog-to-Digital Converter. This device is used to digitize audio and video. An ADC for digitizing video must be capable of sampling at 10 to 150 million samples per second (MSPS). 
add edit  An edit added between consecutive frames in a sequence segment within the Timeline. An add edit separates segment sections so the user can modify or add effects to a subsection of the segment. 
additive colour Colour mixture by the addition of light of the three primaries, red, green, and blue.
additive mix A mixing process that adds the colour value of a pixel in one source clip to the value of a corresponding pixel in a second source clip, and assigns the resulting value to the corresponding pixel in the output clip.
ADR  1. Automatic display replacement. The process of looping playback of a selected region in a sequence and automatically recording multiple replacement takes. 2. Automatic dialog replacement in film. Also called dubbing
advance The separation between a point on the sound track of a film and the corresponding picture image.
Advanced Television Systems Committee (ATSC) The group that recommended the new digital television standards to the FCC. They defined the SDTV and HDTV standards for the United States, using MPEG-2 for video and Dolby Digital for audio. Other countries are also adopting the ATSC HDTV standard. 
AES  Audio Engineering Society. The primary international organization of users and producers of professional audio. The AES maintains a standards committee that supervises the work of several subcommittees and working groups covering various fields of sound reinforcements. 
AES/EBU The digital audio standard set by the Audio Engineering Society and European Broadcast Union and used by most forms of digital audio from CDs to D1.
AFM Abbreviation for audio frequency modulation; the most common form of audio recording found in most consumer and professional video recording decks, especially in VHS and 8mm recorders. AFM audio is limited in dynamic range and frequency response, and can include stereo and multi-track audio.
AIFF Audio Interchange File Format. This is the format for both compressed and uncompressed audio data.
AIFF-C  Audio Interchange File Format-Condensed. A sampled-sound file format that allows for the storage of audio data. This format is primarily used as data interchange format but can be used as a storage format as well. OMF Interchange includes AIFF-C as a common interchange format for noncompressed audio data. 
aliasing Defects in the picture caused by too low a sampling frequency or poor filtering. Usually seen as "jaggies" or stair steps in diagonal lines.
alpha channel The fourth channel of a 32-bit RGB image that creates transparency in the image. The other three channels are red, green, and blue. 
Alpha Mix This is a way of combining two images. How the mixing is performed is provided by the alpha channel. The little box that appears over the left-hand shoulder of a news anchor is put there by an alpha mixer. Wherever the little box is to appear, a "1" is put in the alpha channel. Wherever it doesn't appear, a "0" is used. When the alpha mixer sees a "1" coming from the alpha channel, it displays the little box. Whenever it sees a "0", it displays the news anchor. Of course, it doesn't matter if a "1" or a "0" is used, but you get the point. 
ambient Natural, or surrounding light in a clip.
American Standard Code for Information Interchange, (ASCII) Unformatted text characters that are interchangeable across platforms and applications. Also referred to as "plain text".
Ampex Digital Optics, (ADO) Trade name for digital effects system manufactured and sold by Ampex.
amplitude The maximum distance an oscillating body (e.g., a pendulum) or wave travels from a mean point.
Amplitude Modulation, (AM) A method of encoding data onto a carrier, such that the amplitude of the carrier is proportional to the data value. 
 
analog Analog information is represented electronically as a continuously varying electronic signal.
analog recording  The common form of magnetic recording where the recorded waveform signal maintains the shape of the original waveform signal. All videotape source footage is analog. When recorded or digitized (via telecine transfer), footage is converted from the analog format to a digital format. 
analog video A video signal made of a continuous electrical signal. Your television and VCR can be analog video devices. To be stored and manipulated on a computer, analog video must be converted to digital video.
anamorphic Distortion in viewing of images or geometry related to the difference between computer monitor screen aspect ratio (in which pixels are square) and broadcast, projected or frame aspect ratio (in which image pixels are wider than they are high).
Ancillary Timecode, (ATC) BT.1366 defines how to transfer VITC and LTC as ancillary data in digital component interfaces. 
animatic Limited animation consisting of art work shot and edited to serve as a video tape storyboard. Commonly used for test commercials.
animation The recording of a sequence of still artwork or objects in a way that makes them appear to move on film or video. 24 fps is considered the appropriate speed for animation.
animation curve A curve depicting the interpolation between the various keyframes.
answer Smoothing, removing, or reducing jagged edges along the lines and curves in text, images, or geometry.
answer print The first print combining picture and sound submitted by the laboratory for the customers' approval.
Anti-Alias Filter A lowpass filter used to bandwidth-limit a signal to less than one-half the sampling rate. 
anti-aliasing A technique that smooths jagged edges in computer-generated text or graphics. The manipulation of edges (e.g., those between areas with contrasting colors) in an image, graphic, or text to make the edges appear smoother. Anti-aliased edges appear blurred up close but smooth at normal viewing distance. Anti-aliasing is important when working with high-quality graphics for television use. Contrast with aliasing.
aperture The opening which allows light to pass through a camera lens. An adjustable diaphragm is used to control the size of the opening. 

Effective Aperture
An adjustable diaphragm is used to control the size of the opening. The apparent diameter of a lens viewed from the position of the object against a diffusely illuminated background, such as a sky. 

Picture Aperture 
The rectangular opening in a metal plate at which each frame of the motion picture film is situated during exposure, printing or projection. 

Relative aperture 
The ratio of the focal length of a lens to its effective aperture for an object located at infinity.

Aperture Delay Aperture delay is the time from an edge of the input clock of the ADC until the time the ADC actually takes the sample. The smaller this number, the better. 
Aperture Jitter The uncertainty in the aperture delay. This means the aperture delay time changes a little bit each time, and that little bit of change is the aperture jitter. 
architecture In digital video, architecture (sometimes also known as format) refers to the structure of the software responsible for creating, storing, and displaying video content. A architecture may include such things such as compression support, system extensions, and browser plug-ins. Different multimedia architectures offer different features and compression options, and store video data in different file formats. QuickTime, RealVideo, and MPEG are examples of video architectures (though MPEG is also a type of compression). 
Artifacts A side effect in video or audio caused by signal processing. In the video domain, artifacts are blemishes, noise, snow, spots, whatever. When you have an image artifact, something is wrong with the picture from a visual standpoint. Don't confuse this term with not having the display properly adjusted. For example, if the hue control is set wrong, the picture will look bad, but this is not an artifact. An artifact is some physical disruption of the image. 
ASA Exposure Index or speed rating that denotes the film sensitivity, defined by the American National Standards Institution. Actually defined only for black-and-white films, but also used in the trade for colour films.
Aspect Ratio The ratio of the width of the picture to the height. Displays commonly have a 4:3 or 16:9 aspect ratio. Program material may have other aspect ratios (such as 20:9), resulting in it being "letterboxed" on the display. 
aspect ratio  The numerical ratio of a viewing area's width to its height. In video and television, the standard aspect ratio is 4:3, which can be reduced to 1.33:1 or simply 1.33. HDTV video format has an aspect ratio of 16:9. In film, some aspect ratios include: 1.33:1, 1.85:1, and 2.35:1. 
assemble edit Adding material that has a different signal to the end of a pre-recorded section of a video tape. Adding an assemble edit to the middle of an existing segment causes an abrupt and undesirable change in the sync of the video signal. Contrast with insert edit.
asynchronous When digital communication (e.g., that between computers) is not synchronized by a mutual timing signal or clock.Refers to circuitry without a common clock or timing signal. 
ATM  Asynchronous transfer mode. A network technology based on transferring data in packets of a fixed size. The packet used with ATM is relatively small compared to units used with older technologies. The small, constant packet size allows ATM equipment to transmit video, audio, and computer data over the same network and ensures that no single type of data ties up the line. Current implementations of ATM support data transfer rates of 25 to 622 Mb/s (megabits per second). This compares to a maximum of 100 Mb/s for Ethernet, the current technology used for most local area networks (LANs). 
ATR  Audiotape recorder. A device for recording and reproducing sound on magnetic recording tape. 
ATSC Advanced Television Systems Committee. They defined the SDTV and HDTV standards for the United States, using MPEG-2 for video and Dolby Digital for audio. Other countries are also adopting the ATSC HDTV standard. 
ATSC A/49 Defines the ghost cancellation reference signal for NTSC. Download the specification. 
ATSC A/52 Defines the (Dolby Digital) audio compression for ATSC HDTV. Download the specification. 
ATSC A/53, A/54 Defines ATSC HDTV for the USA. Download the A/53 and A/54 specifications. 
ATSC A/57 Defines the program, episode, and version ID for ATSC HDTV. Download the specification. 
ATSC A/63 Defines the method for handling 25 and 50 Hz video for ATSC HDTV. Download the specification. 
ATSC A/65 Defines the program and system information protocol (PSIP) for ATSC HDTV. Download the specification. 
ATSC A/70 Defines the conditional access system for ATSC HDTV. Download the specification. 
ATSC A/90 Defines the data broadcast standard for ATSC HDTV. Download the specification. 
ATSC A/92 Defines the IP multicast standard for ATSC HDTV. Download the specification. 
attenuation A decrease in an electrical signal's amplitude.
Attic folder  The folder containing backups of your files or bins. Every time you save or the system automatically saves your work, copies of your files or bins are placed in the Attic folder, until the folder reaches the specified maximum. The Attic folder copies have the file name extension .bak and a number added to the file name. The number of backup files for one project can be changed (increased or decreased) in the Bin Settings dialog box. 
attribute clip  A mechanism that applications can use to store supplemental information in a special track that is synchronized to the other tracks in a track group. 
audio effects board Similar to a switcher, an audio effects board is the primary router and mixer for source audio, and for adjusting, mixing, and filtering audio. Usually, a digital audio workstation is used to perform more complex audio work.
Audio Modulation Refers to modifying an audio subcarrier with audio information so that it may be mixed with the video information and transmitted. 
audio scrub  See scrubbing. 
Audio Subcarrier A specific frequency that is modulated with audio data. 
audio subframe There are 100 subframes of audio for every frame of video.
audio sweetening  The mixing of sound effects, music, and announcer audio tracks with the audio track of the edited master tape, usually during the mixing stages of a production. Also called audio postproduction for video. 
audio timecode  Longitudinal timecode (LTC) recorded on an audio track. 
AudioVision  A registered trademark of Avid Technology, Inc. A digital, nonlinear audio editing system that locks digital video in sync with audio for audio editing and sweetening. 
auto-assembly The automatic assembling of an edited video tape on a computerized editing system (controller), based on an edit decision list (EDL). Auto-assembly is used in assemble editing.
Automatic Frequency Control (AFC) A technique to lock onto and track a desired frequency. 
Automatic Gain Control, (AGC) A circuit that automatically adjusts audio or video input levels.
AutoSave  A feature that saves your work at intervals you specify. Backups are placed in the Attic folder. 
AUX  Auxiliary track. In a video editing system, a channel reserved for connecting an external audio device, video device, or both. 
AV Abbreviation for audiovisual; the making use of or relating to both hearing and sight and to electronic media in general.
AVI Abbreviation for Audio-Video Interleaved; the algorithm created by Microsoft for synchronizing and compressing analog audio and video signals. AVI is also the file format used by Video for Windows
Avid disk  The disk on the Macintosh platform that contains the operating system files. The computer needs operating system information in order to run. 
Avid Projects folder  The folder containing your projects. 
AVR  Avid Video Resolution. The compression level at which visual media is stored by the Avid system. The system creates media in a particular AVR using proprietary conversion algorithms to convert analog video to digital form.
axis the component of an object that you use to determine its two or three dimensional space and movement.
B'-Y' The blue-minus-luma signal, also called a color difference signal. When added to the luma (Y') signal, it produces the blue video signal. 
b-frame Bi-directional frame. The frame in an MPEG sequence created by comparing the difference between the current frame and the frames before and after it.
B-mode  "A ""checkerboard"" or nonsequential method of assembly. In B-mode, the edit decision list (EDL) is arranged by source tape number. The edit system performs all edits from the tapes currently assigned to decks, leaving gaps that will be filled by material from subsequent reels. See also A-mode, C-mode, D-mode, E-mode, source mode. "
b-mode edit An editing method where the footage is assembled in the order it appears on the source reels. Missing scenes are left as black holes to be filled in by a later reel. Requires fewer reel changes and generally results in a faster edit session.
B-roll Refers to secondary or duplicated footage of a fill or secondary nature usually played from the B source player in an A/B-roll linear editing system. B roll does not refer to all tapes played from the B source player.
backplane PCB (printed circuit board) on a Movie-2 bus connector.
backtiming  A method of calculating the IN point by subtracting the duration from a known OUT point so that, for example, music and video or film end on the same note. 
backup  A duplicate copy of a file or disk in another location if the original file or disk becomes corrupted. See also Attic folder. 
balanced cable In audio systems, typically refers an a specific cable configuration that cancels induced noise.
Bandpass Filter A circuit that allows only a selected range of frequencies to pass through. 
Bandwidth (BW) The range of frequencies a circuit will respond to or pass through. It may also be the difference between the highest and lowest frequencies of a signal. 
Bandwidth Segmented Orthogonal Frequency Division Multiplexing BST-OFDM attempts to improve on COFDM by modulating some OFDM car­riers differently from others within the same multiplex. A given transmission channel may therefore be "segmented", with different segments being modu­lated differently. 
bar code  A pattern of vertical stripes of varying width and spacing that encodes information. Bar codes can be used to encode timecode on film. 
base board Printed circuit board (and mounted components such as integrated cirucuits, etc.) that is inserted into the computer's expansion slot. A module board isoften attached to the base board.
Baseband When applied to audio and video, baseband means an audio or video signal that is not modulated onto another carrier (such as RF modulated to channel 3 or 4 for example). In DTV, baseband also may refer to the basic (unmodulated) MPEG stream. 
batch capture The automated process of capturing clips in a list. (see batch list) 
batch digitize  The automated process in which groups of clips, sequences, or both are digitized (recorded digitally). 
batch list A list of clips to be batch captured. 
batch record  The automated process in which groups of clips, sequences, or both are digitized (recorded digitally). 
baud  The number of electrical oscillations that occur each second. Baud was the prevalent measure for bandwidth or data transmission capacity, but bps (bits per second) is used most often now and is more accurate. 
BBC British Broadcasting Corporation. 
beam the directed flow of bombarding electrons in a TV picture tube.
beam-splitter prism The optical block in a video camera onto which three CCD sensors are mounted. The optics split the red, green and blue wavelengths of light for the camera.
Bento  A registered trademark of Apple Computer, Inc. A general container format and software API (application programming interface). Bento is used by OMF Interchange as a storage and access system for the information in an OMF Interchange file. 
best light  A telecine transfer performed with optimum settings of the color grade controls but without precise scene-by-scene color correction. 
Betacam, Betacam SP  Trademarks of Sony Electronics, Inc. Two component videotape and video recording standards. Sony Betacam was the first high-end cassette-based system, recording video onto 1/2-inch magnetic tape. The SP version arrived 3 years after the first Betacam, improving on signal-to-noise ratios, frequency responses, the number of audio channels, and the amount of tape available on cassettes. SP is now the only type sold. 
bezier A curve that connects the vertices of a polygon; each vertex has two tangents, or handles, which you can use to adjust the slope of the adjacent curve or side of a polygon.
bi-phase Electrical pulses from the tachometer of a telecine, used to update the film footage encoder for each new frame of film being transferred.
bicubic surface A surface that you can add to a layer with four control handles that you can use for four-point tracking.
bid sheet A written estimate, or quote, for video or production services.
bilinear surface A surface that you can add to a layer with more than four control handles for creating non-linear effects.
bin  A database in which master clips, subclips, effects, and sequences are organized for a project. Bins provide database functions to simplify organizing and manipulating material for recording, digitizing, and editing. 
BIOS Basic Input/Output System settings for system components, peripherals, etc. This information is stored in a special battery-powered memory an is usually accessible for changes at computer start-up.
bit One binary digit. An eight-bit byte can define 256 brightness or colour values.
bit rate The amount of data transported in a given amount of time, usually defined in Mega (million) bits per second (Mbps). Bit rate is one means used to define the amount of compression used on a video signal. Uncompressed D1 has a bit rate of 270 Mbps. Mpeg 1 has a bit rate to 1.2 Mbps. HDTV has a bit rate of 1.5Gbps (giga bits per second).
bit stream A continuous series of bits, commonly used to describe a large file such as MPEG video that is read as a stream instead of all at once.
BITC Burned-In Time Code. The timecode information is displayed within a portion of the picture, and may be viewed on any monitor or TV. 
bitmap A pixel-by-pixel description of an image. Bitmap images are also referred to as raster images.
black and code  Video black, timecode, and control track that are prerecorded onto videotape stock. Tapes with black and code are referred to as striped or blacked tapes. 
black box A term used to describe a piece of equipment dedicated to one specific function.
black burst  A video signal that has no luminance or chrominance components (except burst) but contains all the other elements of a video signal. Black burst is the reference signal commonly used for timing audio and video samples. An electronic device that emits a signal that registers as pure black when recorded on videotape. 
black edits  1. A video source with no image. 2. A special source you can fade into, out of, or use for other effects.
Black Level This level represents the darkest an image can get, defining what black is for a particular video system. If for some reason the video goes below this level, it is referred to as blacker-than-black. You could say that sync is blacker-than-black. 
black point  The luminance value in a video image that you set to be equal to reference black when making a color adjustment. Compare with white point. 
black stripe See striping.
blacked tapes  See black and code. 
blackout The fading of a video signal to black to indicate, for example, the end of a show.
blanket fee Typically used for musical selections. One who pays a blanket fee has permission to use the musical selection the fee covers in an unlimited number of released projects and videos. 
blanking Portions of the video signal during which both camera and receiver complete a scan line (horizontal blanking) or field (vertical blanking), and retrace to begin the next scan. Blanking is the part of the video signal that contains no picture information. This is the time that the scanning beam in a TV picture tube is blanked to allow it to track back to the beginning without drawing diagonal lines across the screen.
blanking level The level of a video signal separating the range that contains synchronizing information from the range that contains picture information. Also known as a pedestal. 
bleach 1. Converting a metallic silver image to a halide or other salt which can be removed from the film with hypo. When bleaching is not carried to completion, it is called reducing. 2. Any chemical reagent that can be used for bleaching.
Blooming This is an effect, sometimes caused when video becomes whiter-than-white, in which a line that is supposed to be nice and thin becomes fat and fuzzy on the screen. 
blue screen  A special effects procedure in which a subject is photographed in front of a uniformly illuminated blue or green background. A new background image can be substituted for the blue or green during the shoot or in postproduction through the use of chroma key. 
BNC connector Standard twist-connector for attaching coaxial cable to professional video equipment.
bps  Bits per second. The standard measure of data transmission speeds. 
break-down The separation of a roll of camera original negative into its individual scenes.
Breezeway That portion of the video waveform between the trailing edge of horizontal sync and the start of color burst. 
brightness (1) The intensity of a color as determined on a scale from black (no brightness) to white (maximum brightness). The combination of brightness, hue, and saturation determines the appearance of the colors of a polychromatic image, whereas the brightness alone determines the appearance of a monochromatic image's color. (2) The luminance of a video signal. (3) The brightness of a monitor or video projector measured in lumens.
broadcast monitor Television set without receiving circuitry, wired directly to a VTR or other output device.
broadcast quality A quality standard for composite video signals set by the NTSC and conforming to FCC rules. If you plan to record video signal or videotape for broadcast, it is important to note that devices providing NTSC signals do not necessarily meet FCC broadcast standards.
BS.707 This ITU recommendation specifies the stereo audio specifications (Zweiton and NICAM 728) for the PAL and SECAM video standards. Purchase the specification. 
bspline A smooth curve that passes on the inner side of the vertices of a polygon to connect the vertices to interpolate or draw the polygon. 2. A curve used to define a motion path.
BST-OFDM See Bandwidth Segmented Orthogonal Frequency Division Multiplexing. 
BT.1119 Defines the widescreen signaling (WSS) information for NTSC and PAL video signals. For (B, D, G, H, I) PAL systems, WSS may be present on line 23, and on lines 22 and 285 for (M) NTSC. Purchase the ITU specification. 
BT.1124 Defines the ghost cancellation reference (GCR) signal for NTSC and PAL. Purchase the specification. 
BT.1197 Defines the PALplus standard, allowing the transmission of 16:9 programs over normal PAL transmission systems. Purchase the specification. 
BT.1302 Defines the transmission of 16:9 BT.601 4:2:2 YCbCr digital video between pro-video equipment. It defines a parallel interface (8-bit or 10-bit, 36 MHz) and a serial interface (360 Mbps). Purchase the specification. 
BT.1303 Defines the transmission of 16:9 BT.601 4:4:4:4 YCbCrK and RGBK digital video between pro-video equipment. Two parallel interfaces (8-bit or 10-bit, 36 MHz) or two serial interfaces (360 Mbps) are used. Purchase the specification. 
BT.1304 Specifies the checksum for error detection and status for pro-video digital interfaces. Purchase the specification. 
BT.1305 Specifies the digital audio format for ancillary data for pro-video digital interfaces. Purchase the specification. Also see SMPTE 272M. 
BT.1358 720 x 480 (59.94 Hz) and 720 x 576 (50 Hz) 4:2:2 YCbCr pro-video progressive standards. Purchase the specification. Also see SMPTE 293M. 
BT.1362 Pro-video serial interface for the transmission of BT.1358 digital video between equipment. Two 270 Mbps serial interfaces are used. Purchase the specification. 
BT.1364 Specifies the ancillary data packet format for pro-video digital interfaces. Purchase the specification. Also see SMPTE 291M. 
BT.1365 Specifies the 24-bit digital audio format for pro-video HDTV serial interfaces. Purchase the specification. Also see SMPTE 299M. 
BT.1366 Specifies the transmission of timecode as ancillary data for pro-video digital interfaces. Purchase the specification. Also see SMPTE 266M. 
BT.1381 Specifies a serial digital interface-based (SDI) transport interface for compressed television signals in networked television production based on BT.656 and BT.1302. Purchase the specification. 
BT.470 Specifies the various NTSC, PAL, and SECAM video standards used around the world. SMPTE 170M also specifies the (M) NTSC video standard used in the United States. BT.470 has replaced BT.624. Purchase the specification. 
BT.601 720 x 480 (59.94 Hz), 960 x 480 (59.94 Hz), 720 x 576 (50 Hz), and 960 x 576 (50 Hz) 4:2:2 YCbCr pro-video interlaced standards. Purchase the specification. 
BT.653 Defines the various teletext standards used around the world. Systems A, B, C, and D for both 525-line and 625-line TV systems are defined. Purchase the specification. 
BT.656 Defines a parallel interface (8-bit or 10-bit, 27 MHz) and a serial interface (270 Mbps) for the transmission of 4:3 BT.601 4:2:2 YCbCr digital video between pro-video equipment. Purchase the specification. Also see SMPTE 125M. 
BT.709 This ITU recommendation specifies the 1920 x 1080 RGB and 4:2:2 YCbCr interlaced and progressive 16:9 digital video standards. Frame refresh rates of 60, 59.94, 50, 30, 29.97, 25, 24, and 23.976 Hz are supported. Purchase the specification. 
BT.799 Defines the transmission of 4:3 BT.601 4:4:4:4 YCbCrK and RGBK digital video between pro-video equipment. Two parallel interfaces (8-bit or 10-bit, 27 MHz) or two serial interfaces (270 Mbps) are used. Purchase the specification. 
BTSC This EIA TVSB5 standard defines a technique of implementing stereo audio for NTSC video. One FM subcarrier transmits a L+R signal, and an AM subcarrier transmits a L-R signal. 
bug An error in a computer program.
bump-up Copying from one recording medium onto another that is more suitable for post-production purposes because, for example, it offers better bandwidth or timecode capabilities.
bumping up  The transfer of a program recorded on a lower quality videotape to a higher quality videotape (such as from 3/4-inch to 1-inch videotape, or S-VHS to MII). 
burn-in  A visible timecode permanently superimposed (burned in) on footage, usually in the form of white numbers in a black rectangle. Burned-in timecode is normally used for tracking timecode during previews or offline editing. A videotape with burn-in is also called a burn-in dub or window dub. 
burn-in-dub A duplicate of an original or master tape that includes the time code reference on-screen and is used as a reference for logging and locating scenes.
burnt-in timecode Time code numbers that are superimposed on the picture, generally created using the overlay feature of a VTR. Used for rought-cut and edit-list processing. Also called burn in.
burst The part of the sync signal that controls the hue and color accuracy of television pictures. 
Burst Gate This is a signal that tells a video decoder where the color burst is located within the scan line. 
bus 1. Electrical signal path between different physical connection points. 2. System bus on computers, represented by the expansion slot connectors. 3. Movie-2 bus.
BVB  Black-Video-Black. A preview mode that displays black, newly inserted video, and then black again. 
byte A sequence of bits. In general, the amount of memory needed for one character (for example, the letter A) of a specified size, usually 8 or 16 bits.
C-mode  A nonsequential method of assembly in which the edit decision list (EDL) is arranged by source tape number and ascending source timecode. See also A-mode, B-mode, D-mode, E-mode, source mode. 
calibrate  To fine-tune video levels for maximum clarity during digitizing (from videotape). 
camcorder A combination camera and recording device that records continuous pictures and generates a signal for display or recording.
Camera Control Unit (CCU) The remote control device used to set parameters for one or more television cameras.
camera log A record sheet giving details of the scenes photographed on a roll of original negative.
capstan servo The regulating device of the capstan as it passes tape through a video tape recorder.
capture The process of digitizing video or audio material, usually from a VTR, and storing it in a file on a hard disk.
capture card Sometimes called a capture or video board, the logic card installed into a computer and used to digitize video. Or, for video that is already digitized, the device that simply transfers the file to the hard disk. Using a hardware or software codec, the capture card also compresses video in and decompresses video out for display on a television monitor.
Capture Mask effect  An effect that converts the format of source data during playback. For example, it could convert video frame data between PAL (25 fps) and NTSC (29.97 fps) formats. 
capturing Refers to capturing source video for use on a computer. If analog, the captured video is converted to digital.
Cathode Ray Tube (CRT) Display device, or picture tube, for video information.
CATV Community antenna television, now generally meaning cable TV. 
CBC Canadian Broadcasting Corporation. 
CBR, (Constant Bit Rate) MPEG video compression where the amount of compression does not change.
CCIR Comite Consultatif International des Radiocommunications or International Radio Consultative Committee. The CCIR no longer exists-it has been absorbed into the parent body, the ITU. For a given "CCIR xxx" specification, see "BT.xxx". 
CCIR 601 The standard for digitizing component video. Also sometimes called D1 after the VTR format that first used this signal.
CCITT Abbreviation for Consultative Committee on International Telegraphy and Telephony; the organization that sets standards and makes recommendations for international communication.
CD Abbreviation for compact disc; the digital data storage media proposed by Philips and Sony. CD is the preferred medium for storing digital multimedia files because it is inexpensive and has a fairly large capacity (640 MB).
CD-ROM Abbreviation for compact disc read-only memory; A CD that cannot be written to.
cell animation Also called onion skinning, an animation technique in which a background painting is held in place while a series of transparent sheets of celluloid containing objects are placed over the background painting, producing the illusion of movement. One of the two main types of animation associated with digital video. Compare frame-based 2-D animation. 
cell side The base (celluloid) surface of a strip of film.
CGI Abbreviation for computer graphic imagery. 
CGMS-A Copy Generation Management System - Analog (CGMS-A). See EIA-608. 
change list  A list of instructions produced by Film Composer that is used to track and compare the differences between two versions of a digital sequence. A change list is used to update a work print cutting with specified new edits and revisions. 
change-over In projection, the act of changing from one projector to another, preferably without interrupting the continuity of projection; or, the points in the picture at which such a change is made.
channel  1. physical audio input or output. 2. One of several color components that combine to define a color image. An RGB image is made up of red, green, and blue color channels. In color correction, you can redefine color channels by blending color components in different proportions. 3. See track.
channel editor The tool used to set keyframes and modify animation curves of the channels.
channel hierarchy A set of animation parameters arranged and displayed in a logical group. A group, or upper-level, channel is called a folder. For example, the Camera folder contains channels for camera settings such as position, interest and focal length.
Chaoji VideoCD Another name for Super VideoCD. 
character generator (CG) A device or software application running on a computer and used for creating text for display over video (e.g., titles and credits).
Charge-Coupled Device, (CCD) A light sensitive semi-conductor used as an image sensor in video camera.
chassis  The housing for removable disk modules. The chassis contains a power supply, drives, and connectors for each module. 
checker-board cutting A method of assembling alternate scenes of negative in A and B rolls allowing prints to be made without visible splices.
Checksum An error-detecting scheme which is the sum of the data values transmitted. The receiver computes the sum of the received data values and compares it to the transmitted sum. If they are equal, the transmission was error-free. 
Chroma The NTSC, PAL, or SECAM video signal contains two parts that make up what you see on the display: the intensity part, and the color part. Chroma is the color part. 
Chroma Bandpass In a NTSC or PAL video signal, the luma (black and white) and the chroma (color) information are combined together. If you want to decode an NTSC or PAL video signal, the luma and chroma must be separated. A chroma bandpass filter removes the luma from the video signal, leaving the chroma relatively intact. This works reasonably well except in images where the luma and chroma information overlap, meaning that we have luma and chroma stuff at the same frequency. The filter can't tell the difference between the two and passes everything. This can make for a funny-looking picture. Next time you're watching TV and someone is wearing a herringbone jacket or a shirt with thin, closely spaced stripes, take a good look. You may see a rainbow color effect moving through that area. What's happening is that the video decoders thinks that the luma is chroma. Since the luma isn't chroma, the video decoder can't figure out what color it is and it shows up as a rainbow pattern. This problem can be overcome by using a comb filter. 
Chroma Burst See color burst. 
chroma corrector A device that corrects problems related to a video signal's chroma, color balance, and color noise.
Chroma Demodulator After the NTSC or PAL video signal makes its way through the Y/C separator, the colors must be decoded. That's what a chroma demodulator does. It takes the chroma output of the Y/C separator and recovers two color difference signals (typically I and Q or U and V). Now, with the luma information and two color difference signals, the video system can figure out what colors to display. 
chroma key A video effect wherein a particular area of color (i.e., range of chrominance) is removed from one video signal and replaced with a different signal. This effect is often used during newscasts when a weather map is inserted behind a meteorologist during a newscast.
Chroma Trap In a NTSC or PAL video signal, the luma (black and white) and the chroma (color) information are combined together. If you want to decode the video signal, the luma and chroma must be separated. The chroma trap is one method for separating the chroma from the luma, leaving the luma relatively intact. How does it work? The NTSC or PAL signal is fed to a trap filter. For all practical purposes, a trap filter allows certain frequencies to pass through, but not others. The trap filter is designed with a response to remove the chroma so that the output of the filter only contains the luma. Since this trap stops chroma, it's called a chroma trap. The sad part about all of this is that not only does the filter remove chroma, it removes luma as well if it exists within the frequencies where the trap exists. The filter only knows ranges and, depending on the image, the luma information may overlap the chroma information. The filter can't tell the difference between the luma and chroma, so it traps both when they are in the same range. What's the big deal? Well, you lose luma and this means that the picture is degraded somewhat. Using a comb filter for a Y/C separator is better than a chroma trap or chroma bandpass. 
chrominance The color portion of a video signal that is a mixture of hue and saturation, but not of luminance (brightness). Every color signal has both chrominance and luminance.
chrominance-to-burst phase The difference between the expected phase and the actual phase of the chrominance portion of the video signal relative to burst phase.
chrominance-to-luminance delay The difference in time that it takes for the chrominance portion of the video signal to pass through a system relative to the time it takes for the luminance portion. Also called relative chroma time.
chrominance-to-luminance gain The difference between the gain of the of the chrominance portion of the video signal and the gain of the luminance portion as they pass through a system.
chunking  The transfer on media files in segments so other workgroup users can access and use the media before complete files have been sent. 
CIF Common Interface Format or Common Image Format. The Common Interface Format was developed to support video conferencing. It has an active resolution of 352 x 288 and a refresh rate of 29.97 frames per second. The High-Definition Common Image Format (HD-CIF) is used for HDTV production and distribution, having an active resolution of 1920 x 1080 with a frame refresh rate of 23.976, 24, 29.97, 30, 50, 59.94, or 60 Hz. 
cinch marks Short scratches on the surface of a motion picture film, running parallel to its length; these are caused by improper winding of the roll, permitting one coil of film to slide against another.
cinching  Videotape damage due to creasing or folding. 
cinemascope Trade name of a system of anamorphic widescreen presentation.
Cinepak A commonly used QuickTime codec for compression of video files on CD-ROM. Cinipak offers temporal and spatial compression, and data-rate limiting.
cinex strip A short test print in which each frame has been printed at a different exposure level.
circle take  A take from a film shoot that has been marked for use or printing by a circled number on the camera report. 
Clamp This is basically another name for the DC-restoration circuit. It can also refer to a switch used within the DC-restoration circuit. When it means DC restoration, then it's usually used as "clamping". When it's the switch, then it's just "clamp". 
clean list (clean EDL) An edit decision list (EDL) used for linear editing that has no redundant or overlapping edits. Changes made during off-line editing often result in edits that overlap or become redundant. Most computer-based editing systems can clean an EDL automatically. Contrast with dirty list (dirty EDL). See also, on-line editing.
clip  1. A segment of source material recorded or digitized into your system at selected IN and OUT points and referenced in a project bin. The clip contains pointers to the media files in which the actual digital video and audio data is stored. 2. In a record in a log, which stands for one shot, the clip includes information about the start and end timecode for the shot, the source tape name, and the tracks selected for editing. 3. In OMFI, a general class of objects in the OMF Interchange class hierarchy representing shared properties of source clips, filler clips, attribute clips, track references, timecode clips, and edge code clips. A clip is a subclass of a component. See also master clip, media files, subclip. 
clip properties A clip's specific settings, including frame size, compressor, audio rate, etc. 
clipping The cropping of peaks (overmodulation) of the white or the black portions of a video signal.
Clipping Logic A circuit used to prevent illegal conversion. Some colors can exist in one color space but not in another. Right after the conversion from one color space to another, a color space converter might check for illegal colors. If any appear, the clipping logic is used to limit, or clip, part of the information until a legal color can be represented. Since this circuit clips off some information and is built using logic, it's not too hard to see how the name "clipping logic" was developed. 
clock timecode  See drop-frame timecode. 
Closed Captioning A service which decodes text information transmitted with the video signal and displays it on the display. For NTSC, the caption signal may be present on lines 21 and 284. For PAL, the caption signal may be present on lines 22 and 334. See the EIA-608 specification for (M) NTSC usage of closed captioning and the EIA-708 specification for DTV support. For MPEG-2 video, including ATSC and DVB, the closed caption data are multiplexed as a separate data stream within the MPEG-2 bitstream. It may use the picture layer user_data bits as specified by EIA-708, or in PES packets (private_stream_1) as specified by ETSI EN 301 775. For DVD, caption data may be 8-bit user_data in the group_of_pictures header (525/60 systems), a digitized caption signal (quantized to 16 levels) that is processed as normal video data (625/50 systems), or a subpicture that is simply decoded and mixed with the decoded video. 
Closed Subtitles See subtitles. 
Closeup, (CU)  See also ECU. 
CMYK This is a color space primarily used in color printing. CMYK is an acronym for Cyan, Magenta, Yellow, and blacK. The CMYK color space is subtractive, meaning that cyan, magenta, yellow and black pigments or inks are applied to a white surface to remove color information from the white surface to create the final color. The reason black is used is because even if a printer could print hues of cyan, magenta, and yellow inks perfectly enough to make black (which it can't for large areas), it would be too expensive since colored inks cost more than black inks. So, when black is used, instead of putting down a lot of CMY, they just use black. 
coaxial cable A single conductor, braid-shielded cable used to carry video signals. Has a 75 ohm impedance.
codec Contraction of compression/decompression algorithm; used to encode and decode, or compress and decompress data, such as sound and video files. Common codecs include those that convert analog video signals to compressed digital video files (e.g., MPEG), or that convert analog sound signals into digital sound files (e.g., RealAudio).
Coded Orthogonal Frequency Division Multiplexing Coded orthogonal frequency division multiplexing, or COFDM, transmits dig­ital data differently than 8-VSB or other single-carrier approaches. Frequency division multiplexing means that the data to be transmitted is distributed over many carriers (1,705 or 6,817 for DVB-T, as opposed to modulating a single carrier. Thus, the data rate on each COFDM carrier is much lower than that required of a single carrier. The COFDM carriers are orthogonal, or mutually perpendicular, and forward error correction ("coded") is used. COFDM is a multiplexing technique rather than a modulation technique. One of any of the common modulation methods, such as QPSK, 16-QAM or 64-QAM, is used to modulate the COFDM carriers. 
coefficient recording A form of data bit-rate reduction used by Sony in its Digital Betacam format and with its D-2 component recording accessory, the DFX-C2. Co-efficient recording uses a discrete cosine transformation and a proprietary information handling scheme to lower the data rate generated by a full bit-rate component digital signal. Such a data bit-rate reduction system allows component digital picture information to be recorded more efficiently on VTRs.
COFDM See coded orthogonal frequency division multiplexing. 
color balance Adjustment of the colour circuitry of a TV camera to the colour temperature of the light source for a given scene.
color bars An electronically-generated test signal usually consisting of six vertical strips of colour. A standard test signal that appears as a series of vertical rows of colour by which the chrominance and video levels of a camera's output or a recorded signal can be checked.
color burst The portion of the composite video signal that contains a sample of the color subcarrier. The color burst is used to establish a reference for the color information that follows it, and for decoding the color information of the signal. Burst is many cycles of 3.58 MHz pulses recorded during the horizontal blanking interval and used to establish phase relationships for determining the hue. A color television receiver's color oscillator is phase locked to the color burst.
color correction  The process of adjusting the color characteristics of video material to achieve an accurate representation of color and consistency of color from one clip in a sequence to another. The term generally refers to adjustments made across all the video in a program rather than to individual color changes made as part of a single effect. 
Color Decoder See chroma demodulator. 
Color Demodulator See chroma demodulator. 
Color Difference All of the color spaces used in color video require three components. These might be R'G'B', Y'IQ, Y'UV or Y'(R' - Y')(B' - Y'). In the Y'(R' - Y')(B' - Y') color space, the R' - Y' and B' - Y' components are often referred to as color difference signals for obvious reasons. They are made by subtracting the luma (Y') from the red and blue components. I and Q and U and V are also color difference signals since they are scaled versions of R' - Y' and B' - Y'. All the Ys in each of the Y'IQ, Y'UV and Y'(R' - Y')(B' - Y') are basically the same, although they are slightly different between SDTV and HDTV. 
Color Edging Extraneous colors that appear along the edges of objects, but don't have a color relationship to those areas. 
Color Encoder The color encoder does the exact opposite of the color decoder. It takes two color difference signals, such as I and Q or U and V, and combines them into a chroma signal. 
color frame  "A sequence of video fields required to produce a complete pattern of both field and frame synchronization and color subcarrier synchronization. The NTSC system requires four fields; PAL requires eight. "
Color Key This is essentially the same thing as chroma key. 
Color Killer A color killer is a circuit that shuts off the color decoding if the incoming video does not contain color information. How does this work? The color killer looks for the color burst and if it can't find it, it shuts off the color decoding. For example, let's say that a color TV is going to receive material recorded in black and white. Since the black and white signal does not contain a color burst, the color decoding is shut off. Why is a color killer used? Well, in the old days, the color decoder would still generate a tiny little bit of color if a black and white transmission was received, due to small errors in the color decoder, causing a black and white program to have faint color spots throughout the picture. 
Color Modulator See color encoder. 
color picker A tool used to plot colours in an image.
Color Purity This term is used to describe how close a color is to the theoretical. For example, in the Y'UV color space, color purity is specified as a percentage of saturation and +/-q, where q is an angle in degrees, and both quantities are referenced to the color of interest. The smaller the numbers, the closer the actual color is to the color that it's really supposed to be. For a studio-grade device, the saturation is +/-2% and the hue is +/-2 degrees. On a vectorscope, if you're in that range, you're studio quality. 
color reference burst  The color synchronizing signal included as part of the overall composite video signal. When compared with the color subcarrier signal, the color reference burst determines the hue of the video image. 
Color Reversal Intermediate, (CRI) A duplicate colour negative prepared by reversal processing.
Color Space A color space is a mathematical representation for a color. No matter what color space is used -- RGB, Y'IQ, Y'UV, etc. -- orange is still orange. What changes is how you represent orange. For example, the RGB color space is based on a Cartesian coordinate system and the HSI color space is based on a polar coordinate system. 
color subcarrier The 3.58 MHz (NTSC) or 4.43 MHz (PAL) signal that carries color information. The color subcarrier is superimposed onto the luminance level. Its amplitude represents saturation and its phase angle represents hue.
Color Temperature Color temperature is measured in degrees Kelvin. If a TV has a color temperature of 8,000 degrees Kelvin, that means the whites have the same shade as a piece of pure carbon heated to that temperature. Low color temperatures have a shift towards red; high color temperatures have a shift towards blue. The standard for video is 6,500 degrees Kelvin. Thus, professional TV monitors use a 6,500-degree color temperature. However, most consumer TVs have a color temperature of 8,000 degrees Kelvin or higher, resulting in a bluish cast. By adjusting the color temperature of the TV, more accurate colors are produced, at the expense of picture brightness. 
color timing The process wherein colors are referenced and alternate odd and even color fields are matched to ensure colors match from shot to shot. Most commonly found in high-end equipment, such as Betacam SP.
color wheel  A circular graph that maps hue values around the circumference and saturation values along the radius. Used in the Color Correction tool as a control for making hue offset and secondary color correction adjustments. 
ColorStream, ColorStream Pro, ColorStream HD The name Toshiba uses for the analog YPbPr video interface on their consumer equipment. If the interface supports progressive SDTV resolutions, it is called ColorStream Pro. If the interface supports HDTV resolutions, it is called ColorStream HD. 
Common Image Format See CIF. 
Common Interface Format See CIF. 
compile To compute an image or effect using a nonlinear editing, compositing, or animation program. The result is generally saved in a file on the computer. Also called render. component video
component video  The structuring of the video signal whereby color and luminance signals are kept separate from one another using the color-subtraction method Y (luminance), B–Y (blue minus luminance) and R–Y (red minus luminance), with green derived from a combination. Two other component formats are RGB and YUV. 
composite An analog video signal comprising both luminance and chrominance.
composite blanking See blanking.
composite print A motion picture print with both picture and sound on the same strip of film.
composite sound track  A sound track containing all required sound elements — usually dialog, music, and effects mixed in correct proportions. 
composite sync A signal that comprises only horizontal sync pulses, vertical sync pulses, and equalizing pulses, and has a no-signal reference level.
composite video A signal in which the luminance, chrominance, and sync information are combined into one signal using one of the coding standards (e.g., NTSC, PAL, or SECAM). The signal must take the form of composite video before it can be broadcast or recorded by standard means. Until recently, most monitors and projectors accepted only composite video signals, though many presently accept RGB signals. Contrast with component video.
compositing Layering multiple pictures on top of each other. A cutout or matte holds back the background and allows the foreground picture to appear to be in the original picture.
composition  The standard term used by OMF Interchange to refer to an edited sequence made up of a number of clips. The OMF equivalent of a sequence in an Avid system. 
compression The translation of audio or video data into a format that requires less storage space than the original data. See also, codec.
compression ratio The ratio of the amount of data in the original video compared to the amount of data in the compressed video. The higher the ratio the greater the compression.
Conditional Access This is a technology by which service providers enable subscribers to decode and view content. It consists of key decryption (using a key obtained from changing coded keys periodically sent with the content) and descrambling. The decryption may be proprietary (such as Canal+, DigiCipher, Irdeto Access, Nagravision, NDS, Viaccess, etc.) or standardized, such as the DVB common scrambling algorithm and OpenCable. Conditional access may be thought of as a simple form of digital rights management. Two common DVB conditional access (CA) techniques are SimulCrypt and MultiCrypt. With SimulCrypt, a single transport stream can contain several CA systems. This enables receivers with different CA systems to receive and correctly decode the same video and audio streams. With MultiCrypt, a receiver permits the user to manually switch between CA systems. Thus, when the viewer is presented with a CA system which is not installed in his receiver, they simply switch CA cards. 
confidence value  A measurement, expressed as a percentage, of the probability that the pattern the system finds during a motion tracking operation is identical to the pattern for which the system is searching. During a motion tracking operation, Avid Symphony calculates a confidence value for each tracking data point it creates. 
configuration file Contains a list of the device parameters, resource directory path names, and image file extensions that are required to run fire*.
conform  To prepare a complete version of your project for viewing. The version produced might be an intermediate working version or the final cut. 
conforming The process wherein an off-line edited master is used as a guide for performing final edits.
conforming a film negative  The mathematical process that the editing system uses to ensure that the edits made on a videotape version of a film project (30 fps) are frame accurate when they are made to the final film version (24 fps). 
Console  A display that lists the current system information and chronicles recently performed functions. It also contains information about particular items you are editing, such as the shots in your sequence or clips selected from bins. 
consolidate  To make copies of media files or portions of media files, and then save them on a drive. The Consolidate feature operates differently for master clips, subclips, and sequences. 
constant An option for the interpolation and/or extrapolation of an animation curve that produces a square or stepped curve.
Constant Bit Rate, (CBR) Constant bit rate (CBR) means that a bitstream (compressed or uncompressed) has the same number of bits each second. 
Contouring This is an image artifact caused by not having enough bits to represent the image. The reason the effect is called "contouring" is because the image develops vertical bands of brightness. 
contrast The range of difference between the lightest and darkest values of a picture, or maximum and minimum brightness values.
control point  A location on a Bézier curve that controls its direction. Each control point has two direction handles that can extend from it. 
control track A continuous, stable, low-frequency signal recorded onto tape. It is used to identify frame locations and control the playback of the video signal. Electronic sprocket holes recorded on video tape to guide the heads and control tape transport during playback. A signal recorded on video tape to allow the tape to play back at a precise speed in any VTR. Analogous to the sprocket holes on film.
control track editing The linear editing of videotape with equipment that reads the control track information to synchronize the editing between two decks. Contrast with timecode editing.
control-L See LANC.
convergence (1) The accuracy of the positions of the red, green, and blue beams of a color monitor or projector. (2) The adjustment of the red, green, and blue electron beams in a monitor or video projector to align the red, green and blue images.
CPU  Central processing unit. The main computational section of a computer that interprets and executes instructions. 
crash edit  An edit that is electronically unstable, such as one made using the pause control on a deck, or using a noncapstan served deck. 
crash recording  See hard recording. 
crawl Sideways movement of text across a screen.
crawling text  Text that moves horizontally over time. Examples include stock and sports score tickers that appear along the bottom of a television screen. 
Creepy Crawlies Yes, this is a real video term! Creepy-crawlies refers to a specific image artifact that is a result of the NTSC system. When the nightly news is on, and a little box containing a picture appears over the anchorperson's shoulder, or when some computer-generated text shows up on top of the video clip being shown, get up close to the TV and check it out. Along the edges of the box, or along the edges of the text, you'll notice some jaggies "rolling" up (or down) the picture. That's the creepy-crawlies. Some people refer to this as zipper because it looks like one. 
crop box A box that you superimpose over frames, either automatically or manually, to limit colour corrections, key setups etc., to the area inside the box.
cropping  The redefining of image boundaries, usually by electronically removing the top, bottom, left, or right sides of the image. 
Cross Color This occurs when the video decoder incorrectly interprets high-frequency luma information (brightness) to be chroma information (color), resulting in color being displayed where it shouldn't. 
Cross Luma This occurs when the video decoder incorrectly interprets chroma information (color) to be high-frequency luma information (brightness). 
cross mod A test method for determining the optimum print requirements for a variable area sound track.
Cross Modulation A condition when one signal erroneously modulates another signal. 
crossfade  An audio transition in which the outgoing sound gradually becomes less audible as the incoming sound becomes more distinct. Also called an audio dissolve. See also dissolve, fade. 
Crosstalk Interference from one signal that is detected on another. 
crushing the blacks  The reduction of detail in the black regions of a film or video image by compressing the lower end of the contrast range. 
cue  To shuttle a videotape to a predetermined location. 
cue channel A dedicated track for sync pulses or timecode. 
cue mark Marks used to indicate frames of interest on a clip.
curl A defect of a photographic film consisting of unflatness in a plane cutting across the width of the film. Curl may result from improper drying conditions, and the direction and amount of curl may vary with the humidity of the air to which the film is exposed.
Curves graph  An X, Y graph that plots input color values on the horizontal axis and output color values on the vertical axis. Used in the Color Correction tool as a control for changing the relationship between input and output color values. 
cut  1. An instantaneous transition from one video source to another. 2. A section of source or record tape.
cut list  A series of output lists containing specifications used to conform the film work print or negative. See also dupe list.
cutout See matte.
cutting The selection and assembly of the various scenes or sequences of a reel of film.
CVBS Abbreviation for Composite Video Baseband Signal or Composite Video, Blanking, Synchronization. 
cycles An option for the extrapolation curve that produces cycles in the curve based on the values of the first and last keyframes in the curve.
D-mode  An A-mode edit decision list (EDL) in which all effects (dissolves, wipes, graphic overlays) are performed at the end. See also A-mode, B-mode, C-mode, E-mode, source mode. 
D-to-A converter An electronic device that converts digital signals into analog signals.
D1 Digital video tape format using the CCIR 601 standard to record 4:2:2 component video on 19mm tape. A high quality of video tape format generally available. The first digital video tape format, hence D1.
D16 A format to store film resolution images on D1 format tape recorders. Records one film frame in the space normally used for 16 video frames.
D2 Digital video tape format using the 4fsc method to record composite digital video. Uses 19mm tape and a cassette similar to D1. The second digital video tape format, hence D2. 
D3 Digital video tape format using 4fsc composite signals like D2, but recorded on ˝" tape. The third digital video tape format...
D4 Doesn't exist, so don't worry about it.
D5 Digital video tape format using CCIR 601, 4:2:2 video. Uses the same cassette as D3. Betcha can guess why its called D5.
D9 Digital Video tape format from JVC, before called JVC Digital-S
DAE  Digidesign Audio Engine. A trademark of Avid Technology, Inc. The application that manages the AudioSuite plug-ins. 
dailies The first positive prints made by the laboratory from the negative photographed on the previous day.
dailies  Film prints or video transfers of recently shot film material, prepared quickly so that production personnel can view and evaluate the previous day's shooting before proceeding. Also called rushes, primarily in the United Kingdom. 
DAT Abbreviation for digital audio tape; a digital audio-recording-and-playback system developed by Sony. DAT uses a small, 4mm tape and has a signal quality that can surpass that of the CD. In audio, DAT is often used for mastering a final mix of a sound track or musical composition. In computers, it is often used for archiving or backing up data and may be referred to as DDS (Digital Data Storage).
data rate The amount of data moved over a period of time, such as 10MB per second. Often used to describe a hard drive's ability to retrieve and deliver information.
DAVIC Abbreviation for Digital Audio Visual Council. It's goal was to create an industry standard for the end-to-end interoperability of broadcast and interactive digital audio-visual information, and of multimedia communication. The specification is now ISO/IEC 16500 (normative part) and ITR 16501 (informative part). 
dB Abbreviation for decibels, a standard unit for expressing relative power, voltage, or current. 
dBm Measure of power in communications. 0 dBm = 1 mW, with a logarithmic relationship as the values increase or decrease. In a 50-ohm system, 0 dBm = 0.223 volts. 
dBw Decibels referenced to 1 watt. 
DC 30 editing mode An edit mode in Premiere—specifically for DC30 users—that allows video to be streamed out of the DC30 capture card installed in a computer running Windows. 
DC Restoration DC restoration is what you have to do to a video signal after it has been AC-coupled and has to be digitized. Since the video waveform has been AC-coupled, we no longer know absolutely where it is. For example, is the bottom of the sync tip at -5v or at 1v? In fact, not only don't we know where it is, it also changes over time, since the average voltage level of the active video changes over time. Since the ADC requires a known input level and range to work properly, the video signal needs to be referenced to a known DC level. DC restoration essentially adds a known DC level to an AC-coupled signal. In decoding video, the DC level used for DC restoration is usually such that when the sync tip is digitized, it will be generate the number 0. 
DCT This is short for Discrete Cosine Transform, used in the MPEG, H.261, and H.263 video compression algorithms. 
De-emphasis Also referred to as post-emphasis and post-equalization. Deemphasis performs a frequency-response characteristic that is complementary to that introduced by pre-emphasis. 
De-emphasis Network A circuit used to restore a frequency response to its original form. 
Decibel, (DB) A unit of measure applied to both sound and electrical signals, based on a logarithmic scale. A logarithmic unit that expresses the ratio between a signal and a reference signal. For voltages, dB=20 log (V measured/V nominal). Also referred to as "db's." A logarithmic unit that expresses the ratio between a signal and a reference signal. One-tenth of a Bel, used to define the ratio of two powers, voltages, or currents, in terms of gains or losses. It is 10x the log of the power ratio and 20x the voltage or current ratio. 
Decimation When a video signal is digitized so that 100 samples are produced, but only every other one is stored or used, the signal is decimated by a factor of 2:1. The image is now 1/4 of its original size, since 3/4 of the data is missing. If only one out of five samples were used, then the image would be decimated by a factor of 5:1, and the image would be 1/25 its original size. Decimation, then, is a quick-and-easy method for image scaling. Decimation can be performed in several ways. One way is the method just described, where data is literally thrown away. Even though this technique is easy to implement and cheap, it introduces aliasing artifacts. Another method is to use a decimation filter, which reduces the aliasing artifacts, but is more costly to implement. 
deck controller  A tool that allows the user to control a deck using standard functions such as shuttle, play, fast forward, rewind, stop, and eject. 
decode To divide a composite video signal into its separate components.
decoder A device that decrypts component signals from a composite (encoded) source. Decoders are used in video displays and processing hardware where component signals are needed from a composite source.
decompose  To create new, shorter master clips based on only the material you have edited and included in your sequence. 
definition The aggregate of fine details of a video image on-screen. The higher the definition, the more discernable the details.
degauss  To demagnetize (erase) all recorded material on a magnetic videotape, an audiotape, or the screen of a color monitor. 
deinterlace Separation of field 1 and fie