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Sony 19 mm cassette tape format for digital component video using the CCIR 601 standard, 8 bit, 4:2:2 and non compressed. No generation loss. The first digital video tape format, hence D1.


QuantelĆ format for storing high resolution “Domino” images, on a standard D1 cassette tape. One Domino image occupies the space of sixteen 625 line images, hence the name. The technique allows three high resolution images to be recorded or replayed every two seconds, or viewing resolution at normal speed, on standard monitoring equipment.


A 19 mm cassette tape format for composite digital video using the 4fsc method. The second digital video tape format, hence D2. It is said by some that Ampex developed the D-2 format.


Half inch cassette tape format for composite digital video using the same 4fsc composite signals as D2. The third digital video tape format.


Doesn’t exist, so don’t worry about it. 4 is an unlucky number in Japan and China.


Half inch cassette tape format for component digital video using CCIR 601 and HDTV, 4:2:2 video. Uses the same cassette as D3.  Betcha can guess why it’s called D5. HD D5 uses 4:1 compression and can handle 8 or 10 bits.


Digital HDTV format using D-1 tape. Recording HDTV at 1.2 Gbits per second.


DVCPRO. A digital component format using DCT-based DV compression. Records on 1/4-inch (6.35 mm) tape with 25 Mbits per second video.


There is no D-8, nor will there be. The Television Recording and Reproduction Technology Committee of SMPTE decided to skip D-8 because of the possibility of confusion with similarly named digital audio or data recorders.


Digital-S. A digital component format using DCT-based DV compression. Records on 1/2-inch tape with 50 Mbits per second video.


A Tascam-brand eight track digital audio tape machine using the 8 mm video format of Sony. It has become the defacto standard for audio post production though there are numerous other formats, ranging from swappable hard drives to analog tape formats and everything in between.

D/A (D-A, D/A, D-to-A)

Abbreviation for Digital-to-Analog converter. See also: ADC.


Frame coded according to an MPEG-1 mode, which uses DC coefficients only.

DAC (Digital-to-Analog Converter)

Also called a D to A converter. A device that converts digital signals to analog signals that can be handled by traditional analog circuits–i.e. VCRs, audio amplifiers, video monitors, etc. In a digital video system, the DAC converts digital video to an analog video signal. In a CD drive, it converts the digital information to analog audio that can be used by amplifiers and speakers.

An electronic device that is used to convert digital signals to analog signals, commonly found on video encoders, video pattern generators and computer video graphics equipment.  


Rushes. The first positive prints made by the laboratory from the negative photographed on the previous day.


In an automation system, the database is a group of files that store information about all prepared material. Located on a network drive, or File Sever.

Data Compression

A technique that provides for the transmission or storage, without noticeable information loss, of fewer data bits than were originally used when the data was created.

Data Element

An item of data of data as represented before encoding and after decoding.

Data Encryption Standard (DES)

A national standard used in the United States for the encryption of information digitally transmitted. The standard has been set by the National Bureau of Standards (NBS).

Data Rate

The speed of a data-transfer process, normally expressed in bits per second or bytes per second. The data rate of CD-ROM is 150,000 bytes per second, while the data rate for a typical Magnetic Hard Disk is 1.5 MB per second.

Day of Air

The name of a TCS schedule.

DB (decibel)

A measure of voltage, current, or power gain equal to 1/10 of a bel. Given by the equations 20 log Vout/Vin, 20 log Iout/In, or 10 log Pout/Pin. Each increase of .3 dB equates to a doubling of an electronic signal.
See also: Bel.

DC (Direct Current)

An electrical current which, unlike AC, maintains a steady flow and does not reverse directions. DC cannot be measured in cycles per seconds or Hz. DC current is either generated from a battery or derived from alternating current through a special circuit. Many electronic circuits require DC current in their operation.

DC Coupled

Refers to the specific type of connection used to pass through the AC and DC components of a signal of interest.  Typically, the AC component represents the signal of interest, which rides upon the DC components constant voltage level

DC Restoration

An electronic circuit commonly found in monitors, video test equipment, and video graphics equipment that clamps a part of a waveform at a fixed DC voltage level. This ensures that the picture is always the same brightness, although there may be a slight potential voltage difference between one video device and another.

DCE (Data Circuit Terminating Equipment)

Telecommunications term: equipment at an access point of a network. A modem is a DCE while a personal computer is a DTE (Data Terminal Equipment).

DCT (Discrete Cosine Transform)

1. Discrete cosine transform. A widely used method of data compression of digital video pictures basically by resolving blocks of the picture (usually 8 x 8 pixels) into frequencies, amplitudes, and colors. JPEG and DV depend on DCT.  2. Also an Ampex data videotape format using discrete cosine transform. Also, an Ampex cassette component digital videotape format, conforming to the CCIR 601 standard. It is a rival to Digital Betacam by Sony.

DCT-1 / IDCT  (Inverse Discrete Cosine Transform)

DDR (Digital Disk Recorder.  See: Disk Recorder)

DDS  (Digital Data Service)

DEC  (Decoder)


A unit of measure applied to both sound and electrical signals, based on a logarithmic scale. Also referred to as "dB." in power, 3 dB increase is approximately double the power, a 3 dB decrease is approximately half the power. One decibel is one tenth of a bell.

Decision Point

The point in an interactive program where the user must make a choice, such as selecting an item from a menu or choosing an answer to a question. Choices made at the decision point move the viewer into one of several potential program branches. (See Branches).


A device or circuit used to extract the individual video component signals (R, G, B) from a composite-encoded video source such as NTSC or PAL.

Decoding (process)

The process defined in the Digital Television Standard that reads an input coded bit stream and outputs decoded pictures or audio samples.

Decoding Time Stamp

A field that may be present in a PES packet header that indicates the time that an access unit is decoded in the system target decoder.  Transmitted only if not identical with PTS reference to PID.

Dedicated Network

Videoconferencing term: a network line which is leased full time, providing direct connection between sites.


The basic assignment given to a setting or command


1. To blur an image optically or electronically. 2. An option for the da Vinci 2K that produces selective defocus of both the image and a key.

Delay Line

A device inserted in the path of a video signal to delay the signal for a specific length of time. Often used to match horizontal and subcarrier phase differences due to propagation delays in equipment and cables.


Device or circuit to extract the audio, composite video, and synchronization information from the radio frequency carrier of a video transmission. A tuner on a TV set is such a device.

Default Event

Default material that can be played when backups, standbys, etc. are not available.  Also referred to as alternate event/material/source.


Synonymous with sharpness, detail, quality, or resolution of a video signal.

Delivery System

The computer, video players, and other media equipment actually used to deliver a multimedia program. A delivery system may consist of as little as a videodisc player with an on-board microprocessor, a monitor, and a keypad or may extend to an external computer, two or more monitors, and a variety of peripheral devices.


The description of a signal stripped of its modulated carrier frequency and converted into a standard video signal after broadcast transmission and prior to display. Signals transmitted by antennae, microwave, fiber optics, and other means must be modulated to a special carrier frequency prior to transmission. Once transmission is complete, the signal must be demodulated for recording and display.

Dense Wavelength Division Multiplexing
Dense Wavelength Division Multiplexing (DWDM) is a fairly new technology that enables fiber optic lines to increase in capacity without adding more fiber lines. Contained within a small package placed at either end of a fiber optic line, Dense Wavelength Division Multiplexers allow the transmission of carriers of different colors simultaneously over one fiber optic line. Each color carries a group of signal frequencies, at the same time as other colors, in the same fiber. Increases of 4, 8, 16, and 32 times are presently achieved without the need to deploy added optical fiber. Integral components of this technology are many small, dielectric optical filters that permit selected wavelengths of light to be transmitted.
Approximately five years ago, the International Telecommunications Union (ITU) established definitive wavelengths (frequencies) for signals to be transmitted. Each wavelength was assigned a channel number. In a 200GHz multiplexer, a sequence of either odd or even channels are used. For instance, in building an 8-channel 200GHz multiplexer, one would use either channels 21, 23, 25, 27, 29, 31, 33, and 35 or channels 22, 24, 26, 28, 30, 32, 34, and 36.
This makes a single fiber capable of having up to 32 individual channels. Each channel is on a different color carrier.


Depth of Field

The distance between the first object in focus and the last object in focus within a scene as viewed by a particular lens. Depth of field is affected by choice of lens focal length and aperture. Depth of field increases with shorter focal lengths and smaller aperture openings.


A device that converts serial digital information to parallel digital.


The monitor interface of a computer system. On DUI da Vinci systems each User can define both the color and arrangement of the desktop. From DUI v2.0 multiple desktops will be available. The Desktop settings are stored from the Options menu, and with sessions. They are not stored with Config files.

Desktop Video

Video post production using personal computers at the desktop rather than a traditional post-production environment. Desktop video may include video storyboarding, editing, and/or special effects generation using personal computer equipment rather than dedicated post-production hardware.


Any item of broadcast machinery controlled by the system.

DFD (Displaced Frame Difference)

Differential picture if there is motion.

D/I  (Drop and insert)

A point in the transmission where portions of the digital signal can be dropped out and/or inserted.


A flexible plate within a microphone that vibrates in sympathy with sound pressure waves. It assists in converting the sound energy into an electrical signal.

Differential Gain

Refers to a distortion of the chrominance gain by the luminance level and is expressed as a percentage (%) of how much the chrominance signal is distorted in the amplitude direction.  The smaller the differential gain percentage, then the smaller the distortion.  When differential gain is present, it will manifest itself as changes in color saturation as the luminance (brightness) of the picture changes.

Differential Phase

Refers to a distortion of the chrominance phase by the luminance level and is expressed in degrees of subcarrier phase and indicates how much the chrominance signal is distorted in the phase direction.  The smaller the differential phase, the smaller the distortion.  When differential phase distortion is present, it will manifest itself as changes in hue as the luminance (brightness) of the picture changes.


Circuitry in which data carrying signals are restricted to either of two voltage levels, corresponding to logic 1 or 0. A circuit that has two stable states: high or low, on or off.

Digital Betacam

VTR format using a Sony proprietary, cassette component digital videotape format. 10 bit, compressed 4:2:2 recording to CCIR 601 standard.

Digital chromakeying

Digital chromakeying differs from its analog equivalent in that it can key uniquely from any one of the 16 million colors represented in the component digital domain. It is then possible to key from relatively subdued colors, rather than relying on highly saturated colors that can cause color spill problems on the foreground.
A high-quality digital chromakeyer examines each of the three components of the picture and generates a linear key for each. These are then combined into a composite linear key for the final keying operation. The use of three keys allows much greater subtlety of selection than does a chrominance-only key

Digital Component Video

Digital video using separate color components, such as Y'CbCr or R'G'B'. Sometimes incorrectly referred to as D-1.

Digital Components

Component video signals that have been digitized.

Digital Composite Video

Digital video that is essentially the digitized waveform of (M) NTSC or (B, D, G, H, I) PAL video signals, with specific digital values assigned to the sync, blank, and white levels. Sometimes incorrectly referred to as D-2 or D-3.

Digital Disk Recorder (DDR):

A video recording device that uses a hard disk drive or optical disk drive mechanism. Disk recorders offer nearly instantaneous access to recorded material.

Digital Effects:

Special effects created using a digital video effects (DVE) unit

Digital Film

A generic term for film stored as digital data. In this form the film can be manipulated, edited, and enhanced before being returned back to film or recorded as video. The da Vinci 2K is digital film capable.

Digital Framestore

A memory device that scans and stores a complete frame of video information after the information has been converted from analog to digital form. Digital framestores are used in the creation of digital special effects.

Digital Parallel Distribution Amplifier

A distribution amplifier designed to amplify and fan-out parallel digital signals.

Digital Storage Media (DSM)

A digital storage or transmission device or system.

Digital Video

Minimizes generation loss as information is recorded as a series of numbers. For optimum results, pictures should originate in the digital domain and remain digital throughout post production. More precise and faster sampling improves accuracy.

Digital Word

The number of bits treated as a single entity by the system.


The act of taking analog video and converting it to digital form. In 8 bit digital video there are 256 possible steps between maximum white and minimum black.


The process of changing an electronic analog signal into a discrete binary form. The process is divided into the steps of sampling the analog signal at set moments in time, quantizing each sample (assigning it a numerical value), and translating the sample into a discrete binary number. The advantages of digitization, include reliable high-speed signal transmission, quality duplication, and easy manipulation and processing. A copy of a digital signal is virtually identical to the original. The primary disadvantage of digital signals is their large size resulting in high-storage requirements. Digital compression techniques are helping to overcome this disadvantage.


To convert from analog to digital


A computer-peripheral device that converts an analog signal (images or sound) into a digital signal. With an image, the digitizer may employ an image scanner or a traditional video camera to pick up the image for digitizing.

Digitizing Time

Time taken to record footage into a disk-based editing system, usually from a tape-based analog system, but also from newer digital tape formats without direct digital connections.

Dipole or Dipole Antenna

A dipole antenna is an antenna with two parts and is one half the wavelength of its transmit frequency. Wave length in meters can be calculated as 300,000,000 divided by the frequency in Hz. The wave length (λ) of a transmitter transmitting at 150MHz is 300,000,000 divided by 150,000,000 or 2 meters. The length of a dipole antenna then would be half that amount or one meter in length.

Direct Broadcast Satellite (DBS)

A service that transmits multiple channels of television programming from a satellite to direct to the home.

Direct Color

The process of recording full-bandwidth video information onto videotape. This system is used in the 1-inch Type C and D-2 Digital formats.


Directories are used to store files in a computer. 


A generic name for an optically recorded medium as opposed to “disk” which refers to magnetically recorded material.

Discrete Cosine Transform

A mathematical transform that can be perfectly undone and which is useful in image compression.


A magnetic storage device for computers such as a floppy or a hard disk.


1. Visual readout of stored information.  2. A CRT (Cathode-Ray Tube): a device used to view electronic images; the process of presenting that image.


A dissolve is a gradual transition that creates a smooth, seamless value change over a defined number of frames. A dissolve results in a dynamic event during which the values for each frame are calculated by computer, and the grading controls are locked out. (Lap Dissolve: Mix).

Distribution Amplifier (DA)

A device which converts a single input into multiple outputs which can be distributed to various devices within the system. DAs assure that signal quality is maintained as the signal moves around the system.

Distribution Quality

The level of quality of a television signal from the station to its viewers. For digital television this is approximately 19.39 Mbps.

DNG  (Digital News Gathering)

Electronic news gathering (ENG) using digital equipment and/or transmission.


Domain Name Server. Specific software that runs on a server and resolves domain names to actual IP addresses. Nodes communicate with each other using IP addresses rather than domain names, though users may never see the actual IP addresses being used.

Dolby Digital (formally Dolby AC-3, now also Dolby D)

The approved 5.1 channel (surround-sound) audio standard for ATSC digital television, using approximately 13:1 compression
Six discrete audio channels are used: Left, Center, Right, Left Rear (or side) Surround, Right Rear (or side) Surround, and a subwoofer (considered the ".1" as it is limited in bandwidth). The bit rate can range from 56 Kbps to 640 Kbps.
When moving from analog recording to a digital recording medium, one finds that the digital audio coding used yields an amount of data often too immense to store or transmit economically, especially when multiple channels are required. As a result, new forms of digital audio coding-often known as "perceptual coding"-have been developed to allow the use of lower data rates with a minimum of perceived degradation of sound quality.
Dolby's third generation audio coding algorithm (originally called AC-3) is such a coder.
This coder has been designed to take maximum advantage of human auditory masking in that it divides the audio spectrum of each channel into narrow frequency bands of different sizes, optimized with respect to the frequency selectivity of human hearing. This makes it possible to sharply filter coding noise so that it is forced to stay very close in frequency to the frequency components of the audio signal being coded. By reducing or eliminating coding noise wherever there are no audio signals to mask it, the sound quality of the original signal can be subjectively preserved. In this key respect, a coding system like Dolby Digital is essentially a form of very selective and powerful noise reduction.

Domain Name

The "address" or URL of a particular Web site. You can register your own domain name at www.networksolutions.com.

Domain extensions vary depending on the site in question:

COM - An Internet domain used for business or commercial ventures.

EDU - An Internet domain used for educational facilities.

GOV - An Internet domain used by the government.

MIL - An Internet domain used by the military.

NET - An Internet domain used for network businesses.

ORG - An Internet domain used for non-profit organizations.


Disk Operating System A command line operating system that Windows runs on top of. Bill Gates created DOS while working for IBM.

Dot Crawl

An artifact of NTSC video systems caused by leakage of the chrominance information into the luminance signal, typically seen as a dot pattern crawling up the edges of color areas.  Also known as "cross-luminance".


Strengthening a signal via mixing a delayed version with the original signal.


Receiving or sending information usually via satellite.


To copy a file from a remote computer to your computer. There are a few methods of doing this on the Internet. HTTP, FTP and e-mail attachments are the most common.

Downstream Key(er)

A term which is applied to the final output of the switcher where a key can be created. The downstream key function is used by broadcasters to key their logo over the final program feed, and by producers who wish to further modify their signal by taking advantage of the downstream keyer.

Downwardly Compatible

A feature by which an older format can play material recorded on a newer format. For instance, U-matic® SP tapes can be played back on older U-matic decks while Hi8™ tapes cannot be played back on 8mm equipment.

DPCM (Differential Pulse Code Modulation)

DRAM  (Dynamic Random Access Memory)

High density, cost-effective memory chips (integrated circuits). Their importance is such that the Japanese call them the "rice of electronics." DRAMs are used extensively in computers and generally in digital circuit design, but also for building framestores and animation stores. Being solid state, there are no moving parts and they offer the densest available method for accessing or storing data. Each bit is stored on a single transistor, and the chip must be powered and clocked to retain data.

DRAW Disc (Direct Read After Write)

An analog disc recorder for making a single copy of a videodisc for the purpose of prototyping or checking your program before sending your master tape to be mastered and replicated in the standard optical format. DRAW discs are not compatible with standard laserdisc players and must be played back on a DRAW player or Player/Recorder.

Drive  The data storage device that reads or writes a floppy disk or hard disk.

Driver (Device Driver)

A software program that translates commands between the computer operating system and a peripheral device such as a CD-ROM drive, videodisc player, computer printer, or other device.

Drop Frame

A type of SMPTE time code designed to match clock time exactly. Two frames of code are dropped every minute, on the minute, except every tenth minute, to correct for the fact that color frames occur at a rate of 29.97 per second, rather than an exact 30 frames per second. A second approach:  The video tape time code frame left out to compensate for the discrepancy between recorded tape time and real time. Drop Frame applies only when running at 30 frames per second.  (see Non- Drop Frame).

Drop Frame Editing

Time code editing where video time is corrected for clock time. For every second of time, 29.97 frames of video occur. This creates an error of 3.5 seconds an hour which is corrected by dropping two frames from time code every minute except for the 10, 20, 30, 40, 50, and 60th minutes. The choice when editing for clock time. Only the frame numbers are dropped, not the actual video frames.

Drop Frame Timecode

A type of SMPTE time code designed to match clock time exactly. Two frames of code are dropped every minute, on the minute, except every tenth minute, to correct for the fact that color frames occur at a rate of 29.97 per second, rather than an exact 30 frames per second (see Non-Drop Frame). 

Drop Shadow

Key effect that provides a shadow just behind the key and over the background. This effect is often combined with keyed text to make it more attractive and readable.


Loss of a portion of the video picture signal caused by a lack of iron oxide on that portion of the videotape, or by dirt or grease covering that portion of the tape.


A standard for digital communications channels in North American which communicate at 1.544 Mbps. Also referred to as T-1.  

A telephone company format for transmitting information digitally. DS1 has a capacity of 24 voice circuits at a transmission speed of 1.544 megabits per second.
See also: T1.


A standard for digital communications channels in North American which communicate at 45.304 Mbps. Also referred to as T-3.

A terrestrial and satellite format for transmitting information digitally. DS3 has a capacity of 672 voice circuits at a transmission speed of 44.736 megabits per second. DS3 is used for digital television distribution using mezzanine level compression-typically MPEG-2 in nature, decompressed at the local station to full bandwidth signals (such as HDTV) and then re-compressed to the ATSC's 19.39 Mbps transmission standard.

DSM (Digital Storage Media)

DSM-CC (Digital Storage Media Command and Control)


Digital signal level zero, 64 kbps.


Digital satellite system. An alternative to cable and analog satellite reception initially utilizing a fixed 18-inch dish focused on one or more geostationary satellites. DSS units are able to receive multiple channels of multiplexed video and audio signals as well as programming information, Email, and related data. DSS typically uses MPEG-2 encoding.

DSU (Data Service Unit)

A videoconferencing/telecommunications term: A CPE (Customer Premises Equipment) component which interfaces to a digital circuit such as Tl. The DSU converts the digital data to a format suitable for transmission. The DSU is generally used in conjunction with a CSU (Channel Services Equipment).

DTE (Data Terminal Equipment)

A videoconferencing/telecommunications term: Computer, terminal, or other end-user device that connects to a network through a DCE (Data Circuit-Terminating Equipment).

DTMF Signal

Dual Tone Multi-Frequency.  A set of standardized two-frequency tone combinations, first used by the telephone company, which can be detected by an automation system.  This triggers events, usually commercials which are being inserted into program material such Turnaround (satellite feeds -- CNN…) feeds.  This standard is set by the International Telecommunications Union (ITU) and is CCITT recommendation Q.23 and Q.24.

DTS (Decoding Time Stamp)

DTV Team, The

Originally Compaq, Microsoft and Intel, later joined by Lucent Technology. The DTV Team promotes the computer industry's views on digital television-namely, that DTV should not have interlace scanning formats but progressive scanning formats only. (Intel, however, now supports all the ATSC Table 3 formats, including those that are interlace, such as 1080i.) Internet: www.dtv.org


1. One of the two terms used to describe an audio or videotape duplicate.. To dub is also a term meaning to copy.  2. The computer industry calls the same thing a clone.  The term dub is usually reserved for analog and Clone for digital. 3. The addition of sounds or voices, often in another language, to a film,after shooting.

Dub Cable

Transfers the video information in a component form. (The dub cable does not carry audio). This means that the copied image will have less noise and less image deterioration than if the video signal is run through the line cable. In hard-cut editing, the image quality saved by using a dub cable, in terms of generational loss, is significant. It is possible to run dub cables between different format videotape recorders.


The process of recording material from one source to either the same or different media, such as tape.

Dub List  

A list of all the events that are to be prepared for playout. The dub list is typically generated by a traffic system then translated for use by media preparation systems.


Da Vinci User Interface. The name given to SGI controlled Renaissance 8:8:8 systems to distinguish them from the earlier text based, or "Classic Interface" systems.


Duplicate -- A copy (of a piece of film).

 Dupe Neg.

A duplicate negative, made from a master positive by printing and development or from an original negative by printing followed by reversal development.

Duplex Audio

An audio teleconferencing system which allows all sites to be heard simultaneously. These systems generally do not use voice switches. They operate like normal telephone handsets used between two sites. Sometimes referred to as Open audio.


Copying. The process of making Dubs. Also used to refer to the area where Dubs are made.


Stands for Duration. The timecode length of a spot on a cassette, or the length of an event in real time, as the system plays it to air. The length of time between the SOM and EOM.

DVB (Digital Video Broadcasting)

Set of open, inter-operable standards and system specifications developed by a world-wide consortium providing a complete solution for digital television and data broadcasting across the range of delivery media.  See www.dvb.org.

DVB-C (Digital Video Broadcasting-Cable)

DVB system specification for cable network systems.  Has the same core as the satellite system DVB-S, but the modulation system is based on quadrature amplitude modulation (QAM) rather than QPSK, and no inner-code forward error-correction is needed.


DVB system specification based on the DVB-C cable delivery system but configured for use with microwave frequencies below approximately 10 GHz for direct distribution to viewers' homes enabling a common receiver to be used for both cable transmissions and this type of microwave transmission.


DVB system specification based on the DVB-S cable delivery system but configured for use with microwave frequencies above approximately 10 GHz for direct distribution to viewers' homes.  DVB-MS signals can therefore be received by DVB-S satellite receivers, which need to be equipped with a small 'MMDS' frequency converter, rather than a satellite dish.

DVB-S (Digital Video Broadcasting-Satellite)

DVB system specification of a single carrier, layered system for transmission of digital video, audio and data via satellite in the 11/12 GHz bandwidth.  The core layer is the payload, which is the useful bit-rate.  Surrounding the payload are a series of layers to make the signal less sensitive to errors, and to arrange the payload in a form suitable for broadcasting.  The video, audio, and other data is inserted into fixed-length MPEG Transport Stream packets.  The packetized data constitutes the payload.

DVB-T (Digital Video Broadcasting-Terrestrial)

DVB system specification for the terrestrial broadcasting of digital television signals with 7 ~ 8 MHz channels.  MPEG-2 sound and vision coding forms the payload transmission scheme based on Orthogonal Frequency Division Multiplexing (OFDM).

DVCR (Digital Video Cassette Recorder)


Digital Versatile Disk -- A new format for putting full length movies on a 5" CD using MPEG-2 compression for "better than VHS" quality.

DVE (Digital Video Effects)

A registered trademark of Nippon Electric Company. Refers to video equipment that performs digital effects such as compression and transformation.
Used to manipulate video images: fly-in, squeeze room, rotate spin. DVE effects have been exclusively in the high-end video production domain until recently when low-cost extension boards have become available to accomplish these effects on the Macintosh and other PCs.


Intel Corporation’s Digital Video Interactive is a set of proprietary chips that allows the recording of 72 minutes of full-motion video, 40-hours of digital audio, or a combination of both audio and video on a CD-ROM disc. The video quality is said to rival that of VHS 1/2-inch videotape. DVI is not yet a commercial product.


Digital videotape recorder.

Dwell Time

The amount of time a sequential switcher allows a particular image to remain displayed.

Dye Sublimation

A printing process that produces photo-realistic, hard-copy prints from video and computer imagery. The process uses special dye films affixed to coated paper stock by use of a multi-element thermal head which achieves a smooth, finished blend of dyes.

Dynamic Bandwidth Assignment

The ability to reallocate bandwidth on the fly so that higher resolution channels can share it with lower resolution channels

Dynamic Microphone

A low-impedance type of microphone that operates on electromagnetic principals.

Dynamic Range

Audio Term: The range of acceptable loudness an audio device can handle without distortion.

The highest and lowest signal levels (amplitude) on a given device.

Dynamic Rounding

The intelligent truncation of digital signals. Some image processing requires that two signals are multiplied, for example in digital mixing, producing a 16-bit result from two original 8-bit numbers (see: Byte). This has to be truncated, or rounded, back to 8-bits. Simply dropping the lower bits can result in visible contouring artifacts especially when handling pure computer generated pictures.

Dynamic Rounding is a mathematical technique for truncating the word length of pixels-usually to their normal 8-bits. This effectively removes the visible artifacts and is non-cumulative on any number of passes. Other attempts at a solution have involved increasing the number of bits, usually to 10, making the LSBs (least significant bit) smaller but only masking the problem for a few generations.

Dynamic Rounding is a licensable technique, available from Quantel and is used in a growing number of digital products both from Quantel and other manufacturers.

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