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C D E F G
H I J K L
M N O P Q R S T
U V W X Y Z (Back
Abort: An instruction used to terminate execution of a computer
program or routine.
Active Video: The portion of a video signal that contains picture
Array: A series of like items arranged in a meaningful pattern,
such as a RAM array.
ASCII: American Standard Code for Information Interchange.
Assembly: A major part of a system that consists of more than
one component. For example, the main control panel is an assembly
within the model 3000. (Also see Component and System.)
Asynchronous: A mode of computer operation where the CPU immediately
begins a new task upon completion of the previous task. (Also
Audio Mixer: An electronic device that takes audio signals from
any of several sources (such as microphones, tape recorders, etc.)
to produce audio effects. (Also see Video Switcher.)
Auto Transition: A linear automatic transition made by pressing
a button (AUTO TRANS) instead of moving a lever arm.
Background Video: (1) Video that forms a background scene into
which a key may be inserted. (2) A video output generated by the
BACKGROUND generator within a switcher for use as background video
in key effects.
Baud Rate: The transmission rate (in bytes per second) of data
between communication devices such as computers, modems, and/or
BETA Format: A color difference video format that uses the Y,
R-Y, B-Y components.
Binary: A numbering system based on just two digits, 0 and 1.
(Also see Hex and Octal.)
Bit (Binary Digit): A single unit of information in a storage
device. (Also see Byte and Word.)
Black: A black video output generated within the switcher and
selected by the BLACK pushbuttons on the crosspoint buses and
by the PST BLK pushbutton.
Blanking: (1) The portion of the video signal during which the
picture is shut off to keep the screen dark during vertical and
horizon-tal retrace. (2) A standard signal from a television sync
generator used to create blanking in video.
Blanking Processor: A circuit which strips blanking and sync from
the source video and replaces it with blanking and sync from a
Boot: The process of loading a computer program, usually automatically
(upon power up) or manually (by pushbutton).
Border: One of the title border modes in which a matte is added
around the holes cut by the key signal.
Brightness: The relative intensity of light determined by the
sum of responses of the eye to the component wavelengths.
Buffer: An isolating component used to eliminate the loading of
a driving circuit by the circuit(s) being driven by it.
Bus: A circuit which provides a path for the transfer of information
from any of several sources to any of several destinations.
Bus Master: The device currently in control of the bus in a system
where control is shared between the CPU and one or more other
Byte: A sequence of 8 or 16 bits operated on as a unit. (Also
see Bit and Word.)
Character Generator: An electronic device that produces letters,
numbers, and symbols for video output.
Chroma: The attribute of light combining hue and saturation independent
of intensity. The color perceived is determined by the relative
proportions of the three primaries.
Chroma Key: An insert effect in which the key is derived from
the chrominance information (hue and saturation) of the key source.
Chrominance: The colorimetric difference between any color and
a reference color of equal luminance. The level of chrominance
corresponds to the sensation of saturation.
Clip: A threshold level adjustment to which the key source attribute
(e.g., luminance) is compared for generating a key signal.
CMOS (Complementary Metal Oxide Semiconductor): A family of semiconductors
characterized by low power consumption.
Color Bars: Standard color test signal of (usually) eight colors.
Color Black: A video signal in which the luminance is at the Black
Color Burst: A nine-cycle (NTSC) or ten-cycle (PAL) burst of subcarrier
on the video signal which serves as the reference for establishing
the picture color.
Color Frame: Video frame polarity. To keep the video signal in
phase, color frames must alternate polarity with each frame.
Component: A part of an assembly. (Also see Assembly and System.)
Component Video: A set of video signals (usually three), each
of which represents a portion of the information needed to generate
a full color image.
Composite Video: A video signal which contains both picture and
Control Processor: A circuit used to generate or alter control
Control Signal: A signal used to moderate the mixing of video
CPU (Central Processing Unit): The section of a computing device
that controls and causes the execution of instructions. A CPU
on a single chip is called a microcomputer.
Crosspoint: An electronic switch, usually controlled by pushbutton,
that allows video or audio to pass when the switch is closed.
Crosstalk: Signal interference from one part of a videotape to
CRT (Cathode Ray Tube): A television picture tube.
Cut: A transition between video and/or key video signals where
one signal is instantaneously replaced by another, or where one
signal is instantaneously added or removed.
Debug: To detect and correct malfunctions of a computer or errors
in a computer program.
Degauss: To demagnetize (erase) all recorded material on a magnetic
video or audio tape.
Diagnostics: A program, usually resident in a computer, made up
of routines which check for malfunctions and identify faulty com-ponents.
(Also see Program and Routine.)
Dissolve: A transition where one source of video or audio fades
out at the same time another source fades in.
Download: The process of transferring specific information from
a large device to a (usually) smaller device.
Dub: To make a copy of a video recording.
Dump: To record the contents of internal memory at a given instant
of time as an aid in detecting program errors.
Dupe: A duplicate copy of a videotape.
Duration: The length of time (in hours, minutes, seconds and frames)
that a particular effect or event lasts.
DVE®: A registered trademark of Nippon Electric Corporation
which stands for Digital Video Effects.
Editor: A (usually computerized) system which provides remote
control of VTRs, switchers, and other devices from a control panel.
An Editor enables production of finished video programs which
combine video tape and effects from several sources.
EDL (Edit Decision List): A record of edit decisions made for
a program (in-times, out-times, and effects). Often saved on a
floppy disk, it can be used for Auto Assemble at a later time.
EEPROM (Electrically Erasable Programmable Read Only Memory):
An information storage device on which the information cannot
readily be changed. It is nonvolatile memory in that power conditions
do not effect the information. (Also see PROM, RAM, and ROM.)
E-MEM® : A registered trademark of Grass Valley Group, Inc.
which stands for Effects Memory). It is an effect learned or programmed
into the switcher for later recall.
Error Message: A message generated by the program to identify
a program error or the area in which a malfunction occurs.
Event Number: Number assigned by the editing system to each performed
Exception Processing: The activity of a CPU in response to an
interrupt in its normal execution of instructions.
Execution: The carrying out of a particular set of instructions.
Fade: A dissolve from full video to black or from full audio to
Fade-to-Black: See PRESET BLACK
Fault Isolation: The determination of the cause of a failure by
identifying a defective component or circuit.
Field: One complete scan of the TV screen by the electron beam.
For NTSC, two inter-leaved fields of 262 and 263 raster lines
make up a frame. For PAL, two interleaved fields of 312 and 313
raster lines make up a frame.
File: A collection of related records in a computer system treated
as a unit.
Firmware: Physical devices which house computer programs. (Also
see Hardware and Software.)
Flag: A bit of information used to tell the program that some
condition has occurred.
Flash: Interference or breakup to one field of video, also known
as a hit.
Floppy Disk: An electronic device which is capable of storing
data and programs for ease of retrieval and use by a computer.
(Also see Hard Disk.)
Frame: Two interleaved fields which form one complete picture.
Frame Lock: Synchronization of the video signal with SMPTE time
Freeze Frame: The recording of a single frame of video.
Front Porch: The portion of the video signal that occurs during
blanking and extends from the end of active video to the beginning
Generation: The number of times a dupe is removed from the original
videotaped material. A copy of the original is a second generation
tape, and so on.
GPI (General Purpose Interface): An electronic device containing
switches activated by a remote signal. An editing system controls
various remote components through GPIs.
Grey Scale: Range of luminance levels from black to white.
Hard Copy: A print out on paper of data contained on another media,
such as a monitor or disk.
Hard Disk: An electronic device which is capable of storing large
amounts of data and programs for retrieval and use by a computer.
(Also see Floppy Disk).
Hardware: The electric, electronic, and mechanical equipment used
to perform the tasks controlled by a computer. (Also see Firmware
Head: An electromagnetic device that reads, writes, or erases
information in a storage media, such as a floppy or hard disk.
HEX (Hexadecimal): A numerical notation system using a base of
16. (Also see Binary and Octal).
House Sync: The signal generated in the studio as a reference
for other timing signals.
I/O Device: Equipment used to send information or data signals
to and from a computerized editing system.
In-Point: The beginning of an edit; the first frame that is recorded.
Interface: The method by which assemblies within a system and
independent systems communicate with each other.
Interrupt: A special control signal which informs the CPU that
its attention is needed for some type of exception processing.
Jogging: The process of moving the videotape forward or backward
at a variable rate of speed.
Key: Electronic method of inserting one source of video into another.
Keyboard: A device which displays symbols and functions which
serve to provide a human interface into an electronics system.
Linear Key: A key which is used by the switcher without processing;
clip and gain are bypassed and the key signal is applied directly
to the video switcher.
Load: To transfer data to or from a storage device.
Macro: A function that provides for one keystroke to take the
place of many keystrokes.
Mask: A pattern used to obscure parts of a video key.
Master/Slave: Editing process in which one or more VTRs (slaves)
are controlled by another VTR (master).
Matte: An internally generated flat color signal which is adjusted
for luminance, hue, and chrominance.
Matrix: An array of signal lines whose intersections form crosspoints.
Mix: A transition limit in which the pattern edge between two
video signals is set up with a lever arm and stored in microprocessor
Mix/Effects (M/E): An electronic system capable of processing
video signals with other video or control signals.
Modem: A device that converts signals from a form compatible with
data processing equipment to a form compatible with transmission
facilities (such a telephone lines) and vise versa.
Monitor: A device used for video output.
NAB: National Association of Broadcasters.
Nanosecond (ns): One billionth of a second.
Noise: Interference present in a video picture.
NTSC (National Television Standard for Color): The U.S. standard
for color TV transmission consisting of 525 lines of information
scanned at a rate of 30 frames per second. (Also see PAL.)
OCTAL: A numerical notation system using a base of 8. (Also see
Binary and Hex.)
Off-Line Editing: Editing which produces an Edit Decision List
which will be used to assemble the program.
On-Line Editing: Final editing session in which the finished program
master is assembled.
Open-Ended Edit: An edit that has a start time but no designated
Operating Program: The complex sequence of instructions that
determine the ability of a computer to both sequentially and concurrently
run specific programs. (Also see Program and Routine.)
Out-Point: A designated end of an edit.
PAL (Phase Alternating Line): A color TV standard consisting of
625 lines scanned at a rate of 25 frames per second. PAL is used
in many countries. (Also see NTSC.)
Port: A connection point between a computer and other hardware
Preset Black: A transition mode in which one video signal is faded
to color black before another video signal is faded up.
Preview: To rehearse an edit without recording it.
Printer: A device which converts signals into letters, numbers,
symbols, and graphics for output onto paper. (Also see Hard Copy.)
Program: A complex sequence of instructions which tell the computer
how to receive, process, store and transmit information for a
specific task or related tasks. (Also see Operating Program and
PROM (Programmable Read Only Memory): An information storage device
on which the information once entered cannot readily be changed.
It is nonvolatile memory in that power conditions do not effect
the information. (Also see EEPROM, RAM, and ROM.)
Pulse Count: A method of editing in which the system counts control
track pulses to find locations on the tape.
RAM (Random Access Memory): A computer memory system that allows
the storage and rapid retrieval of information. It is (usually)
considered volatile in that the information is lost if power is
Raster: The area of the TV picture tube that is scanned by the
Reaction Time: The delay (in frames) between the time the operator
sees the desired edit point and the time the in-point or out-point
is actually entered.
Real Time: Actual clock time in which events occur.
Reboot: The process of reloading the computer operating program
Recall: (1) To retrieve a previously per-formed event. (2) To
bring a set up from E-MEM and set up a switcher with it.
Reentry: Entry of a processed video signal into another processing
Register: A storage location in micro-processor memory which is
accessed for storage or recall by one of the pushbuttons on the
Registration: The alignment of various signal components to produce
a more exact video image.
RGB Chroma Key: An insert key effect in which the key signal is
derived from a video signal on the basis of RGB chroma hue and
Scroll: To move up or down a list.
Self Key: An insert key effect in which the key video signal serves
as both the key source and the insert source.
Sequence: An operating mode which allows automatic recall of the
contents of a series of E-MEM registers.
Shadow: A title border mode in which the title border is wider
and appears only to the right and bottom of the key.
Signal-to-Noise Ratio: A measurement of the amount of unwanted
noise present in an audio or video signal.
SMPTE: Society of Motion Picture and Television Engineers.
Software: Computer programs. (Also see Hardware and Firmware.)
Split Key: A key mode in which the key signal and the key video
are from different sources.
Streaking: Video irregularity that appears as dark streaks extending
toward the right side of the picture.
Sync: Synchronization pulses that coordinate the operation of
several interconnected video components.
Sync Roll: Synchronizing and rolling the VTRs for editing purposes.
Synchronous: A mode of computer operation where all task, regardless
of the time they take for execution, are allotted identical time
cycles. (Also see Asynchronous.)
System: A grouping of assemblies which perform multiple related
tasks. (Also see Assembly and Component.)
Terminator: A loop back connector which contains a 75 ohm resistive
load to ensure proper signal levels.
Time Base Corrector (TBC): An electronic device used to correct
video signal instability.
Transition: A change from one picture to another. A transition
can be a wipe, mix, or cut.
Upload: Transferring information from one device to a (usually)
Video Switcher: An electronic device that takes video signals
from any of several sources (such as cameras, VTRs, character
generators, etc.) to produce video effects. (Also see Audio Mixer.)
White Clip: Circuit that corrects positive over-modulation of
a composite video signal.
Wipe: Special effect transition in which one video source wipes
(replaces) over another.
Word: A unit of data which occupies one location in memory and
is acted upon as a unit. (Also see Bit and Byte.)
Workprint: Edited master recording created during off-line editing.