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D1 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. D16 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. D2 A 19 mm cassette tape format for composite
digital video using the 4fsc method. The second digital video tape
format, hence D2. D3 Half inch cassette tape format
for composite digital video using the same 4fsc composite signals as
D2. The third digital video tape format. D4 Doesn’t exist, so don’t
worry about it. 4 is an unlucky number in Japan and China. D5 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. D-6 Digital HDTV format using D-1 tape. Recording HDTV at 1.2 Gbits per second. D-7 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. D-8 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. D-9 Digital-S. A digital component format using DCT-based DV compression. Records on 1/2-inch tape with 50 Mbits per second video. DA-88 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. D-Frame 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. Dailies Database 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. 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) Decibel 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). Decoder 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. Default The basic assignment given to a setting or commandDefocus 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. Demodulator 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. Definition 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. Demodulated 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.
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. Deserializer A device that converts serial digital information to parallel digital. Desktop 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. Device 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. Diaphragm 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. Digital 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. 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. Digitizing 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. Digitization 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. Digitize To convert from analog to digital Digitizer 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. Directory
Disc 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.
Disk A magnetic storage
device for computers such as a floppy or a hard disk. Display 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.
Dissolve 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. DNS 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 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. DOS 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".
Doubling Strengthening a
signal via mixing a delayed version with the original signal. Downlink/Uplink Receiving or sending
information usually via satellite. Download 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. Drop-Out 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. DS-1 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. DS-3 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) DS0 Digital signal level
zero, 64 kbps. DSS 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 Dub 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. Dubbing
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.
DUI 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. Dupe 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. Duplication DUR
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-MC
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-MS
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)
DVD 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. DVI 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. DVTR 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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