Glossary of Digital Photo Terms
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
A
Accelerator Board
A hardware expansion board specifically
designed to accelerate or supplement the performance of a specific computer
function such as CPU processing speed or input/output functions.
Access
To acquire data into a computer
system, typically from a storage device or from an input device.
Access Time
The amount of time that is required
to acquire a block of data from a storage device and read it into the
computer system.
Active-Matrix Display
A type of flat panel LCD display
used in laptop and portable computers. Active matrix displays produce
a superior image to passive matrix displays.
Adaptive Compression
A type of compression software
commonly used to back up files. The method of compression changes with
the type of file, and is not recommended for photographic images because
it may destroy original data.
ADC (Analog-to-Digital Converter)
The device responsible for converting
an analog sample such as a voltage level to a binary quantity, or video
tape to a digitized format.
Additive Colors
The three additive primary colors
are red, green and blue. When these three colors of light are mixed
in equal proportions they will produce white light. Also known as additive
primaries.
Addressable Resolution
The maximum resolution of any
device. The finite number of pixels that any imaging device is capable
of creating, manipulating or imaging.
Adobe Acrobat
Adobe's software application for
creation of Portable Document Format files that can display a document
as it was originally designed without having the particular software
or fonts used to create the file.
Airbrushing
A software tool found in many
image editing programs that simulates the effect of a mechanical airbrush.
Aliasing
The visual stair-stepping of edges
that occurs in an image when the resolution is too low. This can be
caused by improper image sampling or improper image processing.
Algorithm
A mathematical routine that solves
a problem or equation. In imaging, the term is usually used to describe
the set of routines that make up a compression or color management program.
Alpha
The degree of opacity of an image
in computer graphics. Not the same as luminance.
Alpha Channel
An additional eight-bit channel
used by some image editing software applications for masking or additional
image information. Many popular image editing programs use these channels
for saving selections and masks.
Alpha Chip
A Digital Equipment Corporation
produced RISC chip that is known for its processing speed.
Alpha Chip Analog
An electronic signal, tone or
other measure that is continuously variable in its level.
Alternative Media
This refers to a large group of
image output technologies on various substrata.
Anti-Aliasing
A technique used to smooth the
transition between adjacent image areas. The removal or softening of
jagged (aliased) edges by averaging or blending techniques.
AppleTalk
The local area networking system
that was introduced by Apple Computer for use in the Macintosh environment.
Architecture
The particular basic design of
a computer system. Refers to the basic components of the system, specific
bus structure, and the standards, protocols, and instructions that define
a specific microcomputer system.
Archival Storage
The storage of digital data in
long-term, off-line storage devices.
Archive
Storage of selected digital files
for backup or long-term storage.
Array Processor
A specific portion of a large
computer system that assists processing data quickly. An array processor
is sometimes capable of performing several operations simultaneously.
ARTA (Apple Real-Time Architecture)
The architecture of Macintosh
'AV' platforms that integrates audio and visual data.
Artifact
Unwanted visual anomalies or defects
generated by an input or output device, or by a software operation,
that degrade image quality.
Artificial Intelligence
The use of computers to solve
problems and process information in ways that approximate human thought.
Ascender
The portion of a lower case type
character which rises above the main body of the character, as in the
upper half of the letter "b."
ASCII (American Standard Code
for Information Interchange)
A coding system that converts
font characters to standard numeric values.
Aspect Ratio
The relationship of an image's
horizontal length and vertical height. The horizontal length number
is placed first (i.e. 3:2).
Assembly
Combining numerous files to produce
a finished product. Commonly used to describe the process of combining
line work and continuous tone images into a final layout.
ATM (Asynchronous Transfer
Mode)
A high-speed switching technique
that enables the transmission of 155 Mbits (Mega bits) and 622 Mbits
per second in packets.
ATM (Adobe Type Manager)
Adobe's utility program that improves
a computer monitor's display of type at any size.
AV (Audio-Visual)
A generic term used to deal with
animation, audio, video, and CD-I.
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B
Background Processing
Allows assignment of specific
operations to the background while the computer continues to perform
previously assigned instructions.
Banding
Contours or steps in a gradient
produced by an inadequate range of brightness levels available to display
the image. Banding can occur when displaying continuous tone images
on a display using less than 24 bits of color information, or when printing
a gradient that spans an extended distance without an adequate range
of colors to create smooth transitions from shade to shade.
Bandwidth
The amount of data that can be
transmitted. Also, video equipment specifications that indicate the
maximum image resolution that will be possible with that equipment.
Barrel Distortion
Image distortion that spreads
the center dimensions of the picture.
Base Resolution
The Photo CD image resolution
(512 x 768 pixels) that is formatted for display on current consumer
televisions.
4 Base
The 1536 x 1024 pixel image that
is scanned and stored on a Photo CD. This image is ready to be used
by High Definition Television Systems.
Base/4
An image resolution with 1/4 the
number of pixels as Base Resolution.
Base/16
An image resolution with 1/16
the number of pixels as Base Resolution.
16 Base
The 2048 x 3072 pixels image that
is scanned and stored on a Photo CD and suitable for digital imaging
and desktop publishing applications.
64 Base
The maximum resolution image file
that is available on Pro Photo CD disks. This 4000 x 6000 pixel file
produces a 72 megabyte color image.
BASIC (BALUSTRADE Image Sensor)
A specific type of image capture
sensor or CCD that can capture high quality digital images with a single
chip.
Batch Processing
A method that allows for the repetetive
processing of groups of data or several digital files by executing only
one command.
Baud Rate
Used interchangeably with "Bits
Per Second." The unit of measure used to rate the speed at which computer
data can be translated via modem.Typical modem rates are 2,400, 9,600,
14,400, and 28,000 baud.
BBS (Bulletin Board System)
A system that allows computer
to computer connection via modems to copy files or exchange messages.
Bernoulli
A removable hard disk system that
is produced by Isomer Corp.
Beta Site
A business or location that is
involved in testing a specific product just prior to release.
Beta Test
The testing of a software product
in the field under real operating conditions prior to general release.
Bezier Curve
Curved line segments that are
created by establishing endpoints and adjusting anchor points.
Binary
The numbering system used by most
computers that uses only two digits, 0 and 1, to represent all numbers.
Bit
A Binary digit, this is the smallest
piece of binary information used by a computer. A bit will have a value
of either 0 or 1.
Bitmap Graphics
Graphics that are constructed
of individual pixels.
Black
The fourth color in four-color
printing. It is listed as the K in "CMYK." Black is required in the
printing process because equal amounts of cyan, magenta and yellow inks
will not produce a true black.
Black Generation
A term describing the addition
of black ink to the other process colors when separating an RGB color
image into CMYK colors. Black generation is typically handled in one
of two ways, GCR or UCR.
Blanket
In offset printing, a rubber sheet
which is wrapped around a cylinder on a printing press. The inked image
on an exposed metal plate is pressed onto this blanket for transfer
to the paper.
Bleed
Printing term referring to an
image or inked area which extends to the edge of a printed piece. The
bleed is the portion of the artwork that is beyond the trim marks of
the piece. The bleed is required to account for any slight misalignment
during trimming which would otherwise result in an unprinted strip of
paper appearing at the edge of the finished piece.
Blend
In computer graphics software,
the intermediate steps between two objects that are created when the
objects are merged together via a specified number of intermediate transformations.
Blooming
A visual effect caused by exposing
a CCD to too much light. This "digital overexposure" can cause distortions
of the subject and/or color.
Blue
One of the three additive primary
colors of light.
Blur
The softening of image detail.
Blurring of an image is usually accomplished through software averaging
of pixel values to soften edge detail.
BPl (Bits Per Inch)
A term defining the density of
data in a bitmap image.
BPS (Bits Per Second)
A measurement of the speed of
data transfer, used interchangeably with the term baud per second.
Brush
In many image editing programs,
this is the term describing a special effects filter that performs a
specific function, such smoothing selective edges. In some cases, the
image editing programs present the brushes as an icon that actually
looks like a brush.
Bubble Jet
A Canon ink jet printing technology
that creates bubbles in the ink supply and propels the ink through small
nozzles onto the print media.
Buffer
Part of the computer's memory
used for temporary storage of information. This becomes necessary to
compensate for differences in speed that different devices can transmit
or receive data.
Browser
A software tool for accessing
and navigating the World Wide Web.
Burn
In offset printing, the term for
exposing a metal printing plate.
Bus
A data pathway used within a computer
system to transfer information within the system.
Byte
A bundle of data containing eight
bits. This is the common size unit for computer data.
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C
Cache
Temporary storage located between
the hard disk and the computers RAM used to reduce the time needed for
the computer to access data.
Calibration
A process of setting digital imaging
components to standardized settings that will produce accurate and predictable
results in the output.
Camera Ready
Artwork that is ready for photographic
exposure to a printing plate.
Capture
Acquiring information, such as
an image, with a scanner or digital camera device.
Cathode Ray Tube (CRT)
The tube used in televisions and
computer monitors to display the output of the video signal or computer
line information. CRT's use the additive primary colors red, green and
blue.
CCD Array
An arrangement of CCD sensors
mounted in close proximity that allows for the simultaneous capturing
of many pixels with one exposure.
CCD Color Scanner
An input device that uses CCD's
to sample an analog color image and convert the information into a digital
form.
CCD (Charged Coupled Device)
A type of light detection device
used in many popular scanners, digital cameras, and video cameras that
generates electrical current in direct proportion to how much light
strikes areas of the sensor.
CCITT (Consultative Committee
for International Telephony and Telegraphy)
The CClTT has specified standards
for communications throughout the world.
CD (Compact Disc)
A small plastic disc used to store
digital information. A laser is used to read the digital information
from the disc.
CD Interactive (CD-I)
A multimedia system that uses
a CD-ROM XA disc that provides for simultaneous presentation of video,
audio, data and text, allowing the user to interact by responding to
prompts generated by software.
CD-ROM (CD-Read-Only Memory)
A compact disc format that allows
storage of information in a read only format.
CD-R (CD-Recordable)
A CD format that allows the users
to record data to a disc when using the proper hardware. Recorded data
is not erasable.
CD-ROM-XA (CD-ROM Extended
Architecture)
A specific type of compact disc-read
only device that is compatible with the Photo CD format and other CD
applications. Multiple session Photo CD's cannot be fully utilized on
non-XA drives.
CEPS (Color Electronic Prepress)
A high-end digital publishing
system specifically designed for color correction and image assembly.
CGA (Color Graphics Adapter)
A low resolution (200 x 300 pixels)
color video standard for PC-compatible computers.
CGM (Computer Graphics Metafile)
A vector based standard for graphics
files that allows images to be transferred between applications.
Chip
Common term for a computer integrated
circuit.
Choke
In offset printing, a term describing
a trapping relationship between a foreground element, and a background
color or element. To create a trap between a foreground element that
knocks out a background, the background may be "choked" or slightly
encroach into the knockout created by the foreground element. See also
"Spread" and "Trapping".
Chroma
The hue or color information associated
with an image.
Chrominance
The portions of a signal that
are dedicated to describing the hue and saturation. Used in measuring
the difference between two colors of equal brightness.
CHRP (Common Hardware Reference
Platform)
Computer platforms developed by
IBM-Apple that share a common protocol allowing execution in many operating
systems.
CIE (Commission International
de l'Eclairange)
A set of color standards based
on mathematical modeling of human vision and light. CIE color spaces
are used for the communication of color independent of a specific device.
CLC (Color Laser Copier)
Canon's color laser output technology.
Client-Server
An efficient means of storing
large files and applications on a server computer, rather than at the
client computer or desktop workstation. A file server is generally used
to manage files, an image server manages image files and so on. This
is faster than having to move an entire file across a network.
Cloning
The process of producing an exact
copy of existing digital image data, either to another image file or
copying an area of an image within the same file.
Closed Architecture
Computer systems that are "closed
architecture" severely limit the addition of peripheral devices to the
system, especially devices from other manufacturers.
CLUT (Color Look-Up Tables)
A digital color processing technique
that is employed when the display system is not capable of reproducing
all of the colors available in the image. This presents the best possible
combination of colors on the display for predicting accurate color for
the output.
CMY (Cyan, Magenta, Yellow)
These three subtractive primary
colors are used in color-negative printing and in some color output
devices to produce a full gamut of color. The combination of pure CMY
inks produces black, and the elimination of all three produces white.
CMYK (Cyan, Magenta, Yellow
and Black)
The four colors of ink that are
used in "four color process" printing to create the appearance of a
photographic or full color. Black is added to compensate for the lack
of purity in CMY inks.
Coated Paper Stock
A printing paper having a transparent,
smooth layer added to one or both sides that changes the look of the
final printing. Coatings are normally defined as hard glossy, semi-glossy
or matte surfaces.
Color
Color is produced using a combination
of luminance and chrominance signals.
Color Calibration
A system of software and/or hardware
that matches the colors between two or more digital devices. Color calibration
systems commonly compare device color profiles and translate one color
model into a device-independent language that the next color device
can use.
Color Correction
The process of adjusting an image
to compensate for scanner deficiencies or output device characteristics.
Color Curve
A graphic mechanism for displaying
color measurements and for making color changes to an image. User adjustments
to the angle and slope of the curve implement color changes to one or
all of an images color channels.
Color Key
A printer's proofing system developed
by 3M that makes separate acetate sheets of CMYK that when stacked give
a representation of the offset printing of a color image.
Color Management System (CMS)
A combination of software and
or hardware devices used to produce accurate color results throughout
a digital imaging system.
Color Model
Refers to the component colors
used in the image, such as RGB or CMYK. This is also called a Color
Space or Color System.
Color Proof
A color sample that attempts to
represent the final printed image that will result when a piece is offset
printed. Color proofs can be generated from film separations prior to
using the separations to make printing plates.
Color Separation
The electronic or photographic
process of separating a single RGB color image into the three subtractive
primary colors CMY plus K (black) that will be used for reproduction.
These four monochrome films are used to produce the plates in four color
printing.
Color Space
A 3-D system used to describe
a range of colors.
Color System
A concept that relates colors
for description or reproduction. Models in imaging include CIE, PMS
and Photo YCC among others.
Color Temperature
A scale used to refer to the visible
energy system of various light sources. The scale uses degrees Kelvin
as a measure of the mixture on a scale from red to blue white. Daylight
= 5500 Kelvin, a blue-white color. The Tungsten in a light bulb produces
about 3200 Kelvin, an orange color.
Colorimeter
A device for measuring color values.
ColorSense
A color management system developed
by Kodak to deliver predictable color control even when using multiple
computer platforms and software applications.
Colorsync II
A color management software developed
by Apple computer. ColorSync manages the color between digital devices
by comparing each device's color description to the standard CIE color
mode.
Comp
An abbreviation for composite
or comprehensive. A layout that is produced during the design process
providing a preview of the finished print job.
Compact Disc Erasable
A type of compact disc that allows
for the disc to be recorded, erased and re-recorded.
Composite Video
A video signal that includes the
luminance and chrominance signals, along with the burst signal and sync
signals. Composite video signals are transmitted over a single wire.
The standard television signal.
Compression
The process of reducing the size
of a data file, usually accomplished through software processing. This
is used to reduce the required storage space or cut transmission times.
Computer Program
Term used to describe a specific
piece of software for a computer system. Sometimes referred to as an
application.
Computer-to-Plate
A method of applying an image
onto an offset printing plate. The image is transferred from a computer
directly to the device that exposes the image onto the plate, bypassing
the need for separations and film.
Console
Terminology sometimes used to
describe a computer monitor and keyboard.
Contact Print
A photographic print made from
a negative or positive original in contact with a photographically sensitive
film, paper, or printing plate.
Continuous Tone (CT)
An image that consists of a visually
infinite tonal range of colors or gray values. Value changes appear
as a continuous gradient.
Contouring
See "Banding."
Contrast
The measure of difference between
the lightest and darkest values appearing in an image. High-contrast
images contain mainly dark values and white values with few steps or
tones available in the image.
Copy
The text character elements of
a page layout; or to duplicate digital data from one location to another.
Copyright
The legal ownership of artistic
or written material. Assignment of the copyright can be transferred
by contract.
CPU (Central Processing Unit)
The main processing portion of
a computer. This section contains processing and control circuitry along
with internal storage areas.
Cropping
The process of cutting away unwanted
portions of an image. For instance, an image may be cut down to only
include a person's face.
CT Merge
The process of combining two continuous
tone image tiles to create a seamless blending of the two images.
Cyan
One of the three subtractive primary
colors. Produced by mixing equal amounts of blue and green projected
light. Cyan is also one of the four colors used in 4-color printing.
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D
D-RAM (Dynamic Random Access
Memory)
The term describes memory within
the computer that is constantly changing.
DAC (Digital-to-Analog Converter)
Any device capable of converting
discrete digital binary numbers into continuous analog signals or voltages.
DAT (Digital Audio Tape)
A recording format that is commonly
used for data storage and data backup because of its low cost per megabyte.
Data
The numbers that make up a digital
file.
Data Base
An organized collection of data
or information.
Data Compression
The process of reducing the size
of a data file, usually accomplished through software processing.
Datum
The singular of data.
DCS (Desktop Color Separation)
A Computer file format that includes
four EPS files for CMYK and a PICT file for screen display.
DDCP (Direct Digital Color
Proof)
A color proof that is produced
directly from the digital file without creating color separations.
DDES (Digital Data Exchange
Standard)
A set of standards developed by
suppliers and end users of digital image processing hardware and software
to ensure that data could be exchanged between digital prepress equipment
without the need for conversion.
Densitometer
A device used to measure the density
of light transmitted or reflected by paper or film. It is used to check
the accuracy, quality and consistency of an output device.
Density
The degree of opacity of a photographic
film.
Descender
The portion of a lower case type
character which falls below the main body of the character, as in the
lower half of the letter "p".
Descreening
A feature of some scanners that
allow them to eliminate moire patterns that can occur.
Desktop Publishing
The use of desktop computers to
create and perform some prepress operations for printing and publishing.
Device-Independent Color (DIC)
Any color matching system that
is based on a device independent color model, such as ClE, rather than
being based on the color gamut of one particular piece of equipment.
DIF (Data Interchange Format)
A standardized format that allows
for the exchanging of digital data between different programs.
Digit
A single unit from which all data
is built.
Digital
Information or data that exists
as numerical values (1 or 0) based on a binary coding system.
Digital Camera
A filmless camera system. Any
camera system that is capable of converting an analog image info a digital
signal or file.
Digital Duplicates
Reproductions of an image that
are produced by scanning the original analog image to produce a digital
image file, and then imaging the digital file using some variety of
digital printing or recording device.
Digital Halftone
The use of fine pixels to create
the halftone pattern that is then written to film, direct-to-plate or
direct-to-press for printing.
Digital Internegatives
Internegs that are produced by
digitally scanning the original transparency to create a digital file,
and then imaging the digital data using a film recorder to record the
image onto a negative film stock.
Digital Printer
Any printing device that is capable
of translating digital data into hardcopy output.
Digital Signal Processors (DSP)
Microprocessor chips specially
designed to convert, modify and manipulate streams of digitized signals
in real time. These chips allow for faster telephony, faxing, and audio
and video capture and editing.
Digitize
The process of sampling analog
data and converting (quantizing) the signal into a digital data format
usable by a computer.
Digitizer
A device that allows the user
to plot position points on a tablet using a mouse or stylus in order
to input drawing coordinates into a computer system.
DIMM (Dual Inline Memory Module)
Used to add additional RAM memory
to computers.
DIP (Dual In-line Package as
in DIP Switches)
Small switches used on some computer
peripherals in order to change operating settings.
Direct Digital Color Proof
Using any of a number of output
devices to create a proof from the digital file rather than by a photo-mechanical
method.
Direct Memory Access
The ability to use memory without
a software interface.
Direct-to-Press Printing
Printing devices that allow for
the elimination of film separations from the printing process. These
systems utilize a computer controlled system employing lasers to "write"
digital data to a plate that is already mounted on the press.
Disc
The spelling variation of "disk"
referring to compact discs such as Photo CD or other CD-ROM.
Disk Drive
A device that can contain a fixed
or removable spinning disk used for storage of digital data.
Dithering
A process used by some output
devices to simulate shades of gray or color variations with a randomizing
technique that uses varying sizes and shapes of pixel groupings instead
of an ordered array of halftone dotes.
DOS (Disk Operating System)
The main system software that
tells your computer how to work.
Dot
Dots make up an image in color
separations or halftones. Halftone dots will have a fixed density but
have variable size (amplitude modulation).
Dot Gain
The effect produced by the expansion
of individual dots in a halftone screen when printed onto paper. Dot
gain results in a darkening of a printed image and is influenced by
the tendency of different papers to absorb ink.
Dot Matrix
An impact printing process that
uses a series of dots to create all images, lines and text.
Dot Pitch
The distance between the dots
on a computer monitor, typically 0.2 to 0.3 millimeters. The closer
the dots the sharper the image on the monitor.
Download
The process of receiving data
from another computer, server or system.
DPI (Dots Per Inch)
The unit of measure used to describe
the resolution of image files, scanners, or output devices. The measure
of distinct pixels that a device can produce either horizontally or
vertically in one inch.
Drag and Drop
Terminology used to describe an
option in graphical user interfaces where tasks can be accomplished
by simply dragging an icon to a specified area.
Draw Program
A software program that can create
and manipulate object oriented graphics.
Drive Speed
The speed (RPM) that a drive mechanism
rotates. Faster drive speeds allow for faster data transfers.
Driver
A small software program used
to interface with and control a peripheral device such as a scanner
or printer.
Drum Scanner
A type of optical scanner where
the reflective or transmissive art is mounted to a rotating drum. As
the drum spins, light from the image enters a lens allowing the image
to be recorded in a series of fine lines.
Dry Silver Color Process
A printing technology developed
by 3M that constructs the image on a receiver material without the use
of developing solution.
DSP (Digital Signal Processor)
Chips that are designed to facilitate
digital video and audio, along with accelerating image processing.
Duotone
A monochromatic printed image
created by two overlapping halftone screens of different colors; generally
created from a black and white photographic original in order to add
additional tonal range, or to create a tinted or colored appearance.
DVD (Digital Versatile Disc)
A technology similar to Compact
Disc, but far superior in its storage capacity. A DVD can contain about
4.7 GB of data in its single-sided, single-density version, and 18 GB
or more in a double-sided, double-density version, or about 40 times
more than a CD.
DVI (Digital Video Interactive)
A technology that allows for interactive
video by the compression of approximately 70 minutes of video on one
standard CD-ROM.
Dye Sublimation (Diffusion
Transfer)
A color printing technology that
forms the image by delivering gaseous dyes to the receiver material
with a thermal driver. This creates near photographic quality images.
Dynamic Range
The measurable difference between
the brightest highlight and the darkest value that any system can scan,
create, manipulate or write. The range of gray values that a system
can reproduce.
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E
EGA (Extended Graphics Adapter)
A medium resolution (640 x 350)
color display standard in PC compatible computers.
EISA Bus
A type of 32 bit data bus used
in PC's.
Electroinks
These are used in direct-to-press
printing applications. They work in a manner similar to a laser copier's
toners.
Electronic Dot Generation (EDG)
The process used in digital halftone
production that allows negatives or plates to be generated by grouping
micro dots into regular groups to function in the same manner as a photographically
produced halftone.
Electrophotographic Copier
A printing technology that electronically
changes an image area on a metal drum. Toners adhere to the changed
area and are transferred onto paper.
Electrostatic Plotters
A color output technology that
is capable of producing large, simulated continuous tone prints using
CMYK toners applied using a plotter-type printer.
Emulsion Side
The side of photographic film
or paper coated with the silver emulsion. Film output is specified as
emulsion up, or emulsion down.
Encapsulated PostScript (EPS)
A file format developed by Adobe
that stores graphics and text as Postscript language commands that a
printer can read and print. These files contain low resolution preview
files in addition to the high resolution Postscript commands.
Encryption
The process of scrambling a signal
or digital file so that de-scrambling hardware or software is needed
for a receiver to use the image.
Equalization
An image processing technique
where the range of tones or colors in an image file are expanded in
order to produce a more pleasing image.
Error Diffusion
A screening technology used in
digital continuous tone printers where fixed-sized dots are placed based
on image detail and tone values to enhance sharpness and detail while
avoiding posterization problems.
Ethernet
The networking system originally
developed by Xerox that allows for data transfer between computers and
peripherals of up to 10 megabytes per second using coaxial cable.
Extended Architecture
A type of CD-ROM drive that allows
for the use of multisession discs, such as Photo CD.
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F
Feathering
A technique in many image editing
programs that allows for the softening of the edge around a selection.
Fiber Optic Cables
Cables made of very thin glass
fibers that use light pulses to transmit data instead of electricity.
These cables have greater bandwidth than electrical transmission through
wires.
Field Image
An image that is half of a complete
video image (frame). NTSC video contains 525 horizontal lines. A field
image is 262.5 lines that represent a set of either the odd or even
lines of an interlaced video image.
File Converters
Hardware or software that is used
to convert files from one type of file format to another format.
File Format
The particular arrangement of
digital information that is saved from an application program. The method
of arrangement or storage is unique for any particular application program,
but most applications can import and export standardized graphic and
text file formats, such as TIFF, GIF, and EPS graphuics; or RTF or ASCII
text.
Film Recorders (CRT& Drum)
A device used to output digital
files onto film materials. CRT film recorders use a cathode ray tube
and RGB filters to create the film image. Drum-based film recorders/writers
include sheet-fed and roll-fed models and use white light or lasers
to record the image on film.
Filters
Software that is used to modify
digital images by altering the values or arrangement of selected image
pixels.
Firmware
Software that is embedded into
a computer's ROM chips. This information is permanently burned into
the chip and cannot be changed.
FITS (Functional Interpolating
Transformational System)
A software technology that allows
the user to edit very large image files in near real-time by accessing
only the image data being edited.
Fixed Disk
Another term used to describe
a hard disk drive. A hard drive that cannot be removed is a fixed drive.
Flash Memory
A special type of RAM memory that
stores data without electrical current. This type of memory is currently
used in a number of digital cameras and some portable computers through
the use of credit-card sized devices.
FlashPix
An image file format developed
and supported by Eastman Kodak Co., Microsoft Corp., Hewlett-Packard,
Live Picture and other companies. The format uses FITS (see FITS) technology
to facilitate the transmission and manipulation of large image files.
Flat
In offset printing, a paper or
film holding all of the photographic films required to make a particular
printing plate.
Flatbed Scanner
A scanner which utilizes CCD linear
arrays, where the image is placed on a glass platen, and the CCD array
moves past the artwork.
Flexible Disk - See Floppy
Disk.
Flicker
A perceivable fluctuation of the
brightness levels of a displayed image. This problem is often present
in CRT monitors that have a vertical scan rate that is lower than 50
Hz.
Floppy Disk
A magnetically coated removable
disk used for the storage of computer information. Floppy disks come
in two common sizes, 5-1/4 and 3-1/2 inches, and store from 360K to
2.88 MB.
Floptical
A floppy disk storage device that
uses a light beam to accurately position the magnetic head and is capable
of storing 21 MB.
Font
All of the numbers, symbols, and
letters in a single typeface.
FPO (For Positioning Only)
A term used for low resolution
images used in layouts to define the position of images. The FPO is
replaced in the final production process with the original (high resolution)
image file.
Fractal
A mathematically generated pattern
that is reproducible at any magnification or reduction.
Fractal Compression
A type of video compression that
utilizes fractal-based compression algorithms.
Fractal Image
An image that is created by mathematically
generated geometric shapes containing an infinite amount of image detail.
Frame Buffer
An area in RAM memory set aside
to specifically hold the data for the screen display.
Frame Grabber
A computer expansion board that
is capable of digitizing and processing video signals, converting the
video signal to a single digital image that can be read and displayed
by a computer.
Frame Image
A video image that is the combination
of two fields and includes the odd and evenly scanned lines. One frame
represents 1/30 of a second of video viewing time.
FTP (File Transfer Protocol)
The language used to facilitate
the transfer of files from a server on the internet to another location,
such as a desktop computer or another server.
Full Bleed
Printing term used when an image
or background extends to the final trim edge of a printed page.
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G
Gamma
Refers to the slope of the line
that represents image output values versus the image input values. The
term gamma is also sometimes used to describe the contrast of a monitor.
Gamma Correction
The nonlinear tonal correction
editing an images gamma curve. This is typically used to manipulate
image shadow detail and lighten the image without washing out the highlight
areas.
Gamut
The range of colors that are available
in an image or output process.
Gamut Compression
The editing of an image to reduce
the color gamut so that the image can be displayed or output within
the limits of a particular device.
Gamut Mapping
The plotting of an image color
gamut into the CIE color space.
Ganging
Putting a group of images or jobs
on the scanner or press at one time.
Gateway
A computer server that allows
for the connection of different computer networks using protocol conversions.
Gaussian Blur
An image softening effect utilizing
a bell shaped gaussian distribution to apply the softening effect.
Generation Loss
The loss of quality that is unavoidable
in any type of analog duplication such as an interneg. Digital images
do not suffer this loss of quality when duplicated.
Ghosting
The effect of changing an object's
level of opacity.
GIF (Graphics Interchange Format)
A graphics file format common
to online services and the Internet. A GIF utilizes a 1 to 8-bit palette
to minimize file size (pronounced "jiff").
Gigabyte (GB)
Approximately one billion bytes
(1000 Megabytes). The exact number is 1,073,741,824 bytes.
GPIB (General Purpose Interface
Bus)
A standard interface bus popular
on PC compatible computers for connecting peripheral devices.
Gradation
A smooth graduated transition
between two colors or between black and white. Also known as a gradient.
Graphics Accelerator
A computer expansion board that
is specifically designed to increase the performance of graphics software
tasks.
Graphics Tablet
A device that allows the user
to plot position points on a tablet using a mouse or stylus to input
drawing coordinates.
GCR (Gray Component Replacement)
A type of process color separation
which determines the amount of black ink used to replace Cyan, Magenta,
and Yellow in areas where those three inks overlap.
Gray Scale (or Grayscale)
An image containing a range of
gray levels as opposed to only pure black and pure white.
Green
One of the three additive primary
colors of light (Red, Green and Blue).
GUI (Graphical User Interface)
A computer interface or control
system that uses graphical icons to control the computer operations.
The Apple Macintosh interface and Microsoft Windows are examples of
graphical user interfaces.
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H
Halftone
The process of reproducing a continuous
tone image as a series of various sized dots within a fixed grid that
can be reproduced with ink on a printing press. The finer the dot grid
the higher the quality of the reproduction.
Handshaking
This is a method that allows computers
or communications equipment to coordinate transmissions. This is particularly
important in higher speed communications.
Hard Copy
Any kind of printed or proofing
output, as opposed to display on a monitor.
Hard Disk or Hard Drive
A computer storage device that
contains a fixed magnetically coated disk used for storage of digital
data.
HDCP (High Definition Color
Printing)
A specialized color printing process
that uses balanced dot frequency and screen rulings as fine as 625 lpi
to reproduce near-photographic quality images.
HDTV (High-Definition Television)
A television system that incorporates
1000 or more horizontal lines of resolution (twice current standards)
along with a wider aspect ratio and digital quality audio.
Hertz (Hz.)
A scale used for measuring the
number of cycles per second.
Hi-Fi Color
An alternative printing process
that extends the capabilities of printing presses. This system uses
stochastic screening, 6-color printing, and other techniques to expand
the possible color gamut well beyond that of traditional 4-color processes.
Highlight
The brightest/lightest area within
an image.
Histogram
A graphical display which represents
the distribution of tones within an image. The horizontal coordinate
represents each pixel value possible from black to white. The vertical
values indicate the number of pixels in the image that occur at each
value level.
HLS (Hue, Luminance, and Saturation)
A color model that utilizes Hue,
Luminance, and Saturation as the three coordinates.
Holography
A photographic system that uses
laser light to expose film to a pattern developed by the interference
pattern of the laser and the reflection. When these films are viewed
under specific conditions a 3-D image is visible.
Home Page
The main page of a web site. Navigation
of a web site begins from this home page. Most home pages include links
to other pages of the web site.
Horizontal Resolution
The number of vertical lines that
a system is capable of producing (counted on a horizontal axis).
Host
Usually referring to a computer
server that can be accessed over a network
HSB (Hue, Saturation, and Brightness)
A color model that utilizes Hue,
Saturation, and Brightness as the three coordinates.
HSV (Hue, Saturation, and Value)
A color model that utilizes Hue,
Saturation, and Value as the three coordinates.
HTML (Hypertext Markup Language)
A computer language and format
that describes the components of graphics and text material presented
on the World Wide Web in a consistent manner.
HTTP (Hypertext Transfer Protocol)
The method that is used to retrieve
HTML documents on the World Wide Web. This takes place transparent to
the user once the URL (Uniform Resource Locator) address is accessed.
(For example, PMA is located at http://www.pmai.org)
Hue
One of the components of color.
The hue can be specified by the particular wavelengths or by CIE coordinates.
Hybrid Imaging
Electronic imaging systems that
mix traditional silver-halide technologies with digital imaging technologies.
Hyper-Compression
A technology developed by Eastman
Kodak Co. that compresses a photographic image by several hundred times,
reducing the image to just a few bytes of information. It allows an
entire image to be stored in a portion of a barcode or on the magnetic
strip of a credit card. When decompressed and viewed on the monitor,
it produces a low resolution, but recognizable, black-and-white-image.
Hypertext
A document made up from several
blocks of text that are linked within the computer. This process is
used in networks such as the internet or LAN's.
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I
I/0 (Input/Output)
Used to refer to the portions
of a computer that handle the movement of digital data from storage
devices such as hard drives into RAM or other storage devices.
IC (Integrated Circuit)
The use of transistors created
in silicon chips that are used for the various parts of a computer's
circuitry.
Icon
A small graphic or pictorial image
on the screen used to represent digital files or applications, and accessed
using a mouse or tablet.
IHS (Intensity, Hue, and Saturation)
A color model where colors are
expressed by three values representing Intensity, Hue, and Saturation.
Image Processing Board
A hardware expansion board specifically
designed to enable or accelerate the performance of specific image processing
programs or functions.
Imagesetter
A high resolution laser output
device that is used to record bitmapped data onto film or photographic
paper. These devices are available in flatbed and drum models that image
at resolutions of 1000 dots per inch or more.
Import
To access a separate file while
working on a document within an application program for use in that
current document.
Imposition
The process of positioning pages
of a publication into the correct position so that after the job is
printed and folded, the page order will be correct.
Initialize
A preparation stage that equipment
and storage media must go through in order to be ready for a task. The
initialization process clears equipment or media of any old data or
instructions.
Ink Jet
A nonimpact printing technology
where ink droplets are propelled at the paper to form characters or
graphics.
Input
Any type of information that is
fed into a computer system for processing or storage. Input could come
from digital cameras, scanners, storage devices, keyboards, mice, or
a number of other devices.
Interactive
A system where the operators'
input and the application's actions are inter-related. Interactive programs
often permit or require the operator to respond to prompts in order
to move forward in the program.
Interface
The connection between operator
and the system. A keyboard, mouse and monitor can all be considered
to be interfaces between operator and system.
Interlaced, Interlacing
The standard technology applied
to video monitors and television where the odd field is scanned by the
electron guns (every other line) followed by the scanning of the even
lines. This technology is employed in television monitors to reduce
noticeable flickering but interlacing in computer monitors can cause
flickering. The best computer monitors are non-interlaced.
Internal Data Path
The programmed path that data
travels in any given application.
Interpolation
A sampling technique used to increase
the size of an image file by creating more pixels and increasing the
apparent resolution of an image. Interpolation examines the existing
pixel information and creates additional pixels by averaging the existing
values.
IPU (Internal Processing Unit)
The main processing unit that
controls the speed and the operation of a computer.
ISA Bus (Industry Standard
Architecture)
A 16-bit bus for PC compatible
computers that was first introduced in the IBM AT.
ISDN (Integrated Services Digital
Network)
An international standard for
telecommunications that allows for data, video, and voice transmission
over the same phone lines.
ISO 9660
The standard for CD-ROM that covers
physical characteristics, such as the width of tracks, and the logical
parameters such as methods for naming files and extensions. The standards
are set by the International Standards Organization.
IT8
The lT8 committee developed the
standards for the exchanging of digital data in graphic communications
programs and prepress production systems. Also known as Digital Data
Exchange Standard.
IVUE
The file format invented by Live
Picture. This file format uses FITS Technology to allow for near real-time
access to the entire image or selected segments and unlimited image
zooming.
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J
Jaggies
The visual stair-stepping edges,
known as aliasing, that occur in an image when the image resolution
is too low.
Java
A computer language announced
by Sun MicroSystems in 1995 that allows desktop computers on a network
to access only the portion (called an Applet) of an application they
will need. The application itself resides on a networked server, eliminating
the need for a software application to be registered and paid for every
user. It also enhances websites on the internet by making it easier
to integrate video into a homepage.
Jazz Drive
A storage device manufactured
by Iomega that allows for up to one gigabyte of information on a single
low cost storage media.
JPEG (Joint Photographic Experts
Group)
A graphics file format designed
for use with photographs and other color bitmaps. The JPEG format uses
compression algorithms and an "averaging" technique to create files
that are smaller than would be the case with other graphics file formats.
Saving an image as a JPEG files does cause a very minor loss of image
data and in some cases, quality.
Jukebox
A device providing access to a
large number of CD-ROM's by mechanically finding, retrieving and playing
each disk.
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K
K (Kilobyte)
1,024 bytes of computer memory.
Kan Image
A camera system using a vibration
technique to move the CCD to provide higher resolution images.
Kelvin
A temperature measuring scale
used to describe the color of light. The lower the color temperature
the redder the light, and the higher the color temperature the bluer
the light.
KEPS
Eastman Kodak's system to bring
Photo CD to the prepress industry using the Kodak Precision Color Management
System.
Kerning
The fine adjustment of the spacing
between pairs of type characters in a word to create visually pleasing
and consistent spacing.
Knockout
In offset printing, when a foreground
object lays over a background color or object, the foreground object
is said to knockout the background if it replaces the ink that would
otherwise have appeared in the area underlying the foreground object.
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L
LAN (Local Area Network)
Formed by interconnected computers
within a single work site.
Landscape, Landscape Mode
The orientation of an image that
is wider than it is tall; a setting controlling an output device to
properly fit a computer document to the print medium.
Laser Scanner
A scanning device using a laser
light source to record the image.
Lasso
A tool found in many image editing
applications allowing the operator to select an area by drawing around
it.
Leading
In typesetting, the vertical distance
between lines of type; usually measured in points (pronounced Led-ing).
Library
A storage system organized to
retain and give access to files, data, images, programs, etc.
Lightness
A concept often referred to as
brightness that refers to the amount of perceived light reflecting or
emanating from a subject; also refereed to as Luminance.
Line Art
Artwork that is only black and
white, with no other tones included.
Line Screen
A term referring to the organization
of elements of a halftone printing screen. Normally used to define the
density of the screen; i.e. a 133 Line Screen refers to a pattern with
133 halftone dots/inch. A higher or "finer" line screen will create
a sharper, more detailed image.
Linear Scanner
A scanning device that uses a
linear array CCD. The linear array "sees" one line of the image at a
time, and the linear array is moved past the image or the image is moved
past the linear array in steps in order to capture the entire image
area
Linearization
A process that calibrates the
input and the output of tonal slope (gamma) to be equalized.
Local Bus
Part of the architecture of computers
that form pathways for the transmission of data. These are fast pathways
for moving data to RAM.
Lossless Compression
Any compression technique wherein
no loss in image data will occur when the image is compressed.
Lossy Compression
Any compression technique wherein
some loss of image data will occur when the image is compressed.
LPl (Lines Per Inch)
See "Line Screen"
LPM (Line Pairs per Millimeter)
The pixel density of a digital
image measured in millimeters.
Luminance
The lightness or brightness of
an image. A concept and control in some software that changes or imports
only the color lightness information within an image.
LUT (Look-Up Table)
Information tables that allow
an operator or software to use data relating to conversion functions
for a particular device; i.e., there are film LUT's for each output
device that correct the machines color balance to match the film's recording
characteristics.
LZW (Lempel-Ziv-Welch)
A lossless compression technique
common to TIFF files that allows smaller storage sizes.
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M
Macro
A predetermined pattern of key
strokes that are activated to save time when doing a repetitive task
on the computer.
Magenta
A subtractive primary color for
printing. It is made up of equal parts of red and blue projected light.
Magnetic Disk
A storage medium used to record
electronic data by magnetically imprinting on the disk.
Makeready
The steps required to set up a
print run on an offset printing press; also used to describe the first
printed pieces produced by the press while proper press settings are
in the process of being established.
Marquee
A selection tool in image editing
programs typically represented by animated dotted lines that surround
a selected area of an image.
Masking
A technique that allows manipulation
of one area of an image while other areas remain unaffected.
Mass Storage
High volume storage or archiving
systems.
Match Print
A direct digital color proofing
process developed by 3M that allows the printer to see the colors desired
in the final printing.
MCA (Micro Channel Architecture)
The design of computers that allows
expansion through plug-in modules.
Mechanical
Camera-ready-art prepared by conventional
means that is ready to be made into halftone negatives or plates.
Megabyte (MB)
1,048,576 million bytes of computer
memory.
Merging
Putting two or more data files
together. Typically used to describe the merging of two channels of
a bitmap image.
Metafile
Files that can be shared by more
than one application program.
Metamerism
Two colors that appear the same
under certain light conditions while differing under other light conditions.
MHz (Megahertz)
A unit of measure for frequency
that relates to the processing speed of a computer. Equal to one million
hertz.
Microprocessor
A combination of transistors designed
to perform specific tasks. These transistors are designed into silicon
chips to form the central processing unit of a computer.
Mini Discs
A small (3 inch) CD developed
by Sony.
Mirror
A software function that vertically
or horizontally reverses an image.
Mixers
A device that puts together multiple
inputs.
MO Disks (Magneto-Optical)
These use a combination of magnetic
and optical technology to allow for erasable optical storage disks.
Modem
A device that allows a computer
to communicate via phone lines to other communication devices or networks.
Moire
An undesirable pattern effect
that occasionally appears in combinations of overlapping halftone screens.
Changes to screen angles will often eliminate moire patterns.
Moire Pattern
A visual defect that occurs in
half-tone printing when the dots of the different separations used to
create the half-tone image are at the wrong angles (See Screen Angles).
Monitor Calibration
The process used to bring a monitor's
specifications of color, saturation and brightness into synchronization
with the final output device, allowing the user to assume that what
is seen on the screen will be extremely close to the final output in
appearance.
Morphing
Moving smoothly from one image
to another by having the computer animate a sequence transposing points
in the starting image to corresponding points in the final image.
Motherboard
The major circuit board of a computer
that contains processors, acts as a host to the peripherals, and operates
software.
Mouse
A device that when moved across
a surface makes a corresponding motion of the cursor on the computer
screen.
MPEG (Motion Pictures Expert
Group)
A motion picture compression system.
MS-DOS (Microsoft Disk Operating
System)
A major command-line based operating
system for PC's.
Multimedia
A term that is commonly used to
mean a computer presentation incorporating a combination of graphics,
audio, video, and interactivity.
Multiplexing
A single processing channel that
simultaneously allows many tasks or outputs.
Multiscan
A trademark of NEC for a multiscanning
monitor.
Multisession
A designation that means that
data can be written to a Photo CD on more than one occasion.
Multitasking
When a computer can work on more
than one task or program simultaneously.
Multithreading
Similar to multitasking, this
is a chip technology that routes information through more than one channel
in bursts of information, followed by bursts of information from another
task. The two tasks share time on the chip, giving the appearance of
multitasking.
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N
Nanometer
Visible part of the electromagnetic
spectrum ranges from 400-700 NM.
Nanoseconds
A time measurement equal to one-billionth
of a second.
Native Files
The original computer files, in
their original application forms, for a digital graphic or publication;
as opposed to an export format, Postscript print to disk format, or
other transformed format which can no longer be opened and edited by
the original programs used to create the graphic or publication.
Negative
Film containing a reversal of
an image, such that the values of the original are reversed with light
becoming dark, and vice versa.
Network
Interconnecting several computers
or communication devices.
Newton Rings
Concentric multicolored rings
caused by the pressing of film to glass. This can be a problem in scanning
from negatives or transparencies.
Noise
In image editing applications,
a random pattern of unwanted pixels or pixel groupings called artifacts.
Non-Impact Printer
A printing process that transfers
the ink to the paper without pressure.
Non-Interlaced
Refreshing the monitor screen
without using a method that scans odd lines followed by the scanning
of the even lines. This technology is employed in television monitors
to reduce noticeable flickering, but interlacing in computer monitors
can cause flickering. The best computer monitors are non-interlaced.
NTSC (National Television Standards
Committee)
NTSC is the standard television
and video signal configuration used in the United States, Canada, Japan,
Central America and much of South America.
NuBus
A hardware interface in Macintosh
computers that allows the connection of various peripherals or specialized
circuit boards to the computer. Most Macs now use a PCI bus (See PCI).
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O
OCR (Optical Character Recognition)
Software that allows the computer
to convert documents that have been scanned and saved in a graphics
format back into editable text.
ODC (On-Demand Color)
This term typically refers to
short run color printing. These processes include ink-jet, electrostatic
and direct-to-press.
Off-Line Storage
Storage system that is not resident
within the computer and can be removed; i.e., floppy disks, Syquest
disks, etc.
Offset Printing (Offset Lithography)
A common printing process that
makes prints by transferring ink to a rotating "blanket" that contacts
the paper.
OLE (Object Linking and Embedding)
Built into Windows 3.1 and later
versions, including Windows 95. It allows a data file (such as an image
or video and audio clips) to be either linked to another file in an
application that supports OLE, or the data file can actually be embedded
in the application file. If a linked data file is altered, it will automatically
be altered in the application file as well. If a data file is embedded
in the application file, it is protected from alteration by others.
On-Line
A term in relation to private
networks, such as CompuServe, AOL, the Internet or World Wide Web that
refers to being connected or actively participating in various aspects
of these computer communication networks. For instance, on could access
PMA on CompuServe (Go:PMAI) or the World Wide Web (http://www.pmai.org).
On-Line Storage
Storage systems or media device
that is connected to the CPU.
Open Architecture
The design of a computer that
allows additional non-proprietary hardware or software to be used without
factory installation.
Operating System
The system used by the computer
to control basic operation and software applications.
OPI (Open Prepress Interface)
A page layout system where original
photographic images are scanned by the prepress service and low resolution
files of each image are supplied to the page layout designers. The system
later replaces the low resolution for-placement-only images with high
resolution image scans before the final film separations or printing.
Optical Disk
A digital disk storage system
commonly used for mass storage.
Optical Resolution
The maximum physical resolution
of a device. Optical resolution provides better quality than interpolated
resolution which uses software to create additional image information.
Optical Scanner
A device that changes images from
either reflection or transparency medium to digital data.
Optical Storage
A storage device that is designed
to store large amounts of data, CD and "flopticals" the prime examples
of this system.
Orientation (See Landscape
and Portrait)
The direction that the page is
printed; horizontal = landscape, vertical = portrait.
Overprinting
Printing one ink or tint build
over another, most commonly for trapping purposes.
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P
Page Layout
The process and software that
prepares artwork into the page form to be printed.
Pagination
Putting pages of a publication
into order.
Paint Program
A software program that can create
and edit bit mapped images.
PAL (Phase Alternation Line)
A standard for video that is common
in Western Europe, Australia and other countries.
Palette
The range of color or tone available
in the imaging process, or a movable menu of tools or options found
in software applications.
Pantone
A company producing numerous color
matching systems for print and computer applications. The PMS color
matching system is commonly used to represent 3000 distinct colors through
a numbering system.
Pantone Matching System (PMS)
A printing industry-standard set
of color inks.
Parallel Port
This is a channel for 8 bit data
transmission in or out of the computer.
Parallel Processing
When an array of processors or
segments of the CPU work at the same time to speed processing or multi-task.
Passive-Matrix Display -
See Active-Matrix Display
Paste-Up
A traditional method of preparing
artwork where elements are attached to backing by glue, cement or wax.
PCI (Peripheral Component Interface)
Bus
A 32-bit pathway used to connect
peripherals or specialized circuit boards to the CPU.
PCMCIA Memory Cards (Personal
Computer Memory Card Information Association)
A storage memory device the shape
of a thick credit card
PCX (Paintbrush Extension)
A bitmap graphic format for images
common to many PC's.
PDF (Portable Document Format)
An electronic document format
that allows the distribution of digital files across any platform that
can display a document as originally designed and formatted without
having the software application or fonts on the viewing computer. A
reader, such as Adobe Acrobat Reader software, for viewing PDF documents
is free and available on many websites, including http://www.pmai.org.
PDL (Page Description Language)
A specific set of commands and
instructions that allow page information to be printed to an output
device that uses that same language.
Pentium
A CISC microprocessor chip manufactured
by Intel available in IBM type computers.
Peripheral
Any of a number of hardware devices
that extend or enhance the performance of the computer and are not part
of the CPU, though some are mounted inside the case of the computer.
Persistence
The effect of having an image
on a computer monitor remain even after refreshing.
Phase Change Printer
A printer that stores its ink
in a solid form that is liquefied to allow the ink to be deposited on
the receiver.
Phosphor
The chemical substance on the
inside face of a computer screen that illuminates when electrically
charged. The color accuracy and luminance values of phosphors change
over time, necessitating regular monitor calibration if consistent color
is required.
Photo CD
A trademarked Eastman Kodak designed
storage system for photographic images using a CD as media.
Photo Composing
Typically, this term is used to
describe the process of combining all or part of more than one image
into one image, possibly with text.
Photo YCC
A color standard established by
Eastman Kodak that is used to define the color space for digital imaging
in Photo CD and desktop publishing.
Photothermography
A process that uses heat to activate
silver in the print medium.
Pica
A unit of measurement used in
the graphic arts industry. One pica equals approximately 1/6 inch.
PICT
A bitmap picture format.
Pincushion Distortion
A distortion where the image compresses
toward the center with distortion most noticed at the center of horizontal
or vertical edges.
Pixel
A term common in computer imaging
referring to a picture element.
Plasma Display
A display screen that has a gas
contained between two panels. When specific x-axis (horizontal) and
y-axis (vertical) dots on the panels are electrically charged, the gas
in that area glows.
Platform
Refers to the particular proprietary
computer hardware design. This can be a PC, Macintosh, Sun, mainframe,
etc.
Plotter
An output device that generates
color images using multiple passes with colored ink.
Plug and Play
The ability to install equipment
with little or no training or setup.
PMS - See Pantone Matching
System
PMT (Photo Mechanical Transfer)
A print process that uses exposure
of an image to a photographically sensitive paper.
PMT (Photo Multiplier Tube)
A device used in scanners and
film recorders with a good dynamic range and signal-to-noise ratio.
Point
A unit of measurement used in
the graphic arts industry. There are 12 points to a Pica. One point
equals approximately 1/72 inch. See "Postscript Point."
Portrait, Portrait Mode
The orientation of an image that
is taller than it is wide; a setting controlling an output device to
properly fit a computer document to the print medium.
PostScript
A popular page description language
language designed by Adobe. See "PDL."
Postscript Point
A slight revision to the "Point"
measurement unit. A Postscript point is exactly 1/72 of and inch. Most
graphics software utilizes this refined value for a point.
Power PC Chip
A microprocessor chip jointly
developed by Apple, IBM and Motorola that has the capability to run
commonly used operating systems.
PPD
Refers to PostScript Printing
Description, a small file used to describe a particular printers characteristics
and capabilities to a graphics or word processing software program.
PPI (Pixels Per Inch)
Often used interchangeably with
DPI, PPI refers to the number of pixels per inch in an image.
PPP (Point to Point Protocol)
Software that is typically used
to connect a computer to the internet using a modem.
Pre-Flighting
A process of checking a job for
possible problems before the job is sent for final output. This process
is used to find problems such as missing fonts, postscript errors and
color problems.
Prepress
The process of preparing photographic
originals, typography, graphics and illustrations for a printing process.
Pressure Sensitive Pen
A tool that allows for information
to be put into the computer with a stylus in a manner similar to writing
or drawing.
Primary Color
A color that is the basis for
all other color combinations. The primary colors are Red, Green and
Blue (RGB) in light; Cyan, Magenta and Yellow (CMY) in color photographic
printing. In offset color printing, black (K) is added to CMY inks to
more accurately reproduce an image.
Print on Demand
This refers to any number of short
run publishing processes that include both copier technologies and direct-to-press
applications.
Printer Font
Font files that can be reproduced
from the output device. These may vary from fonts that are used in desktop
computers.
Process Color
The colors Cyan, Magenta, Yellow,
plus Black, used for offset printing.
Progressive Scan
A non-interlaced refresh system
for monitors that cuts down on CRT flicker.
Proprietary
The design of programs, systems
or equipment that are owned by an entity. This technology may be licensed
for use in other applications or systems.
Protocol
The steps needed to communicate
or activate an operation or exchange of information in or between computers.
Proxy
A representative version or sample
of a larger image.
Proxy Image
A low resolution image used in
any software programs to show the effects of changes without performing
transformations on high resolution files.
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Q
Quantization, Quantizing
An encoding process that allows
for the reduction of file size.
Queue
The line of events within the
computer or peripheral.
Qwerty
A standard keyboard layout based
on the American standard typewriter.
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R
RAID (Redundant Array of Inexpensive
Disks)
A performance enhancing group
of disks that work together to speed data transfer and access.
RAM (Random Access Memory)
The high-speed portion of the
computer's memory that is held on special chips for use in current applications
or procedures.
RAS (Remote Access Server)
A server that allows access to
various computers through modems.
Raster Image
An image that is defined as a
collection of pixels arranged in a rectangular array. See "Bitmap."
Rasterization
Changing vector type image information
to raster image information.
Raw Data
Data that is not formatted or
processed.
Real-Time
The concept of seeing on the screen
the actions of the computer as though the activity were happening at
a natural pace.
Red
An additive primary color.
Reflective
Refers to print material that
is viewed with the light on the same side of the image as the viewer.
Refresh Rate
The rate at which an image is
redrawn on a CRT. This is needed because the phosphors at each pixel
are stimulated by the electron gun for only a brief time. The faster
the refresh rate, the more stable an image will appear on the screen.
A refresh rate of 72 times per second, or 72 Hz, is the standard for
digital imaging and is near the limit of the human brain to discern
any flickering or instability.
Removable Media
Any storage system that can be
removed from the drive such as a Syquest cartridge.
Rendering
Applying shading and lighting
effects to a two dimensional image to create the look of a three dimensional
object.
Resolution
The particular pixel density of
an image, or the number of dots per inch a device is capable of recognizing
or producing. See "DPI" and "PPI."
Retouching
Removing imperfections or unwanted
portions of an image.
RGB
A color model using red, green,
and blue; the additive primary colors. Video display systems use RGB
data to create screen images.
RIFF (Raster Image File Format)
A storage format used with gray-scale
images.
RIP (Raster Image Processor)
A processor used to convert information
from a graphics application into raster data for output on a printer.
RlSC (Reduced Instruction Set
Computing)
A computer design that speeds
up processing by dividing tasks into smaller computational units.
ROM (Read-Only Memory)
A memory type that cannot be changed
or rewritten, and will not lose information when a computer is shut
down.
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S
S-RAM CD (Static Random Access
Memory CD)
A compact disc that is used to
provide storable RAM.
S-VGA (Super Video Graphics
Array)
A video display format common
to PC's.
Sans Serif
Typefaces that lack serifs. See
"serif."
Saturation
The amount of chroma present in
a color. Pastels are low saturation while bright colors are said to
be highly saturated.
Scan
The process of translating a picture
from artwork or transparency into digital information.
Scan Rate (Refresh Rate)
The rate that a display changes
its image in a given time.
Scanner (Drum, Flatbed and
Slide Scanners)
A device that makes difital image
files from original artwork, prints, slides or negatives.
SCODL
A graphics format common to film
recorders.
Screen
A halftone screen on film used
in conjunction with photographic film or paper to produce a halftone
image from continuous tone art.
Screen Angles
In half-tone printing, these are
the angles at which half-tone screens are placed to avoid moire patterns
on the final image. The most commonly used angles are: Black = 45 degrees;
Magenta = 75 degrees; Yellow = 90 degrees; Cyan = 105 degrees.
Screening
The process of using screens or
digital methods to create halftone screen representations of continuous
tone images.
SCSI (Small Computer Systems
Interface)
The "Scuzzie" is a fast interface
system that allows peripheral devices to connect with the CPU.
SCSI Chain
The SCSI chain is the linking
of SCSI compatible devices such as scanners or storage devices to a
computer via a SCSI port. A SCSI chain may contain up to seven devices.
SCSI Port
The connection used by SCSI devices
to connect to the CPU. Often SCSI devices are used in a series called
a "Scuzzie Chain."
SECAM (System Electronique
Couleur Avec Memorie)
The television and video system
used in France and Russia.
Separations (Seps)
The actual splitting of an image
into the colors that will be used in the printing process. Normally,
Cyan, Magenta, Yellow and Black (CMYK) are the separations for 4-color
printing.
Serif
The small feet or flared ends
at the tips of the strokes, and at the corners or junctions of individual
characters in some typefaces. These typefaces are referred to as serif
faces.
Server
One computer that acts as a networking
device for many interconnected computers
Service Bureau
A company that provides image
services such as scanning or output.
SGO (Second Generation Original)
An output from the imaging process
producing transparencies or negative that will serve as an original
in other operations.
Shade
The brightness or luminance of
an image when compared to a gray scale.
Shadow
Detail or information contained
in dark areas of an image.
Shadow Point
The darkest tone printable in
an image without being black. All tonal values below this threshold
will print as black.
Shadowing
The process of copying ROM information
into RAM.
Sharpening
A picture enhancement making the
image have more distinct borders, areas, lines or tones.
Signature
In offset printing, the printed
sheet containing a number of different pages that have been arranged
to allow; through folding, trimming, and binding; the creation of a
multi-page finished piece.
Silhouetting
A masking or image blocking that
isolates and image from the background.
SIMM Chip (Single Inline Memory
Module)
Used to add additional RAM memory
to computers.
Slide
A mounted 35mm transparency designed
for projection.
Smooth
A process that softens, blurs
or makes an image, color or pattern to appear out of focus.
SMPTE (Society of Motion Picture
and Television Engineers)
An organization that sets standards
for the film and television industry.
Sneakernet
Physically moving a diskette or
media from one station to another to provide a transfer of information
instead of connecting electronically.
Soft Proof
Viewing a digital image with a
monitor instead of generating a hard copy proof.
Soft-Edge Masking
A technique used to isolate a
portion of an image with an edge that allows for a smoother transition
to areas around the masked part.
SPARC (Scalable Process Advanced
RlSC Computer or Scalable Performance Architecture)
A RISC workstation designed by
Sun Microsystems.
Spatial Resolution
The finest image portion that
can be seen at any magnification.
Spectrophotometer
Device used to measure the quality
and accuracy of a color monitor and the film or paper output.
Spline Curve (Bezier Curve)
The linking of a series of points
on a graph with a smooth curve that is mathematically plotted.
Spooler
A function of the computer that
collects output instructions and data before sending them to a printer.
Spot Color
A single color ink used independently
in a printed piece, as opposed to a process color which is used in overlapping
combinations of other process inks to create any of a large spectrum
of colors.
Spread
In offset printing, a term describing
a trapping relationship between a foreground element, and a background
color or element. To create a trap between a foreground element that
knocks out a background, the foreground may be "spread" or slightly
enlarged to overlap beyond the knockout originally created by the foreground
element. See also "Choke."
Step and Repeat
The process of duplicating an
image into a fixed position for use in a printing process. This procedure
can take place within a computer prior to printing out hard copy of
some sort, or by using large cameras to duplicate an existing original
onto photographic film or paper.
Stochastic Screening
A screening process that conveys
the tone of a screened image by varying the number and location of dots
as opposed to varying just the size of dots within a rigid grid.
Stock Photos
An already existing picture that
can be purchased for use instead of having a photograph specifically
made.
String
A sequence of bits of data making
up a command or file.
Stripping
The process of assembling individual
elements to make a composite page for use in the offset printing process.
Stroke
A term referring to a line segment
in a graphics program. Lines or "strokes" can be straight or curved,
open or closed.
Stylus
A tool that is used on a graphic
input tablet as a drawing instrument, or as a mouse.
Sub-Sample
To access and use a small portion
of an image file.
Subtractive Primaries
These are the three colors that
are used to create all other colors in color photographic printing.
(Cyan, Magenta and Yellow)
Superimpose
To place one element over another
to create stacking of images or overlays.
SWOP (Standard Web Off-Set
Printing)
Refers to a set of standards for
conveying and representing color information. This standard is based
on the characteristics of web offset presses.
Syquest Cartridges
A particular style of magnetic
removable storage disks.
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T
Tablet (Graphics Tablet)
An input device that uses a stylus
or specialized mouse to write or draw on the tablet surface to communicate
with the computer.
Tape Storage
A mass storage device that uses
removable tape as a medium.
TARGA (True vision Advanced
Raster Graphics Adapter)
A 24-bit color file format and
expansion board developed by ITT / Truevision.
TCP/IP
Transmission Control Protocol/Internet
Program. Developed by the Department of Defense, this allows different
computer types and platforms to be linked for communicating across a
network. Computers on the internet use TCP/IP to communicate with other
computers on the internet.
Terabyte
1,099,511,627,776 bytes of computer
memory.
Texture Mapping
Putting a texture or image file
on the surface of a 3-D computer image.
TGA (TARGA)
An acronym for a Targa board or
file.
Thermal Autochrome
An image printing technology developed
by Fuji Photo Film that requires no water or chemicals to process. The
color dyes are in a special paper and are activated by heat.
Thermal Transfer
A technology that uses heat to
deposit dye on a receiver material.
32 Bit Color
A digital image format that incorporates
256 shades in 8-bits for each of three color channels (RGB) and includes
a mask (alpha) channel with a possible 256 levels of opacity.
Thumbnail
A small low resolution version
of an image.
TIE (Tagged Image Extraction)
A technology that extracts only
the part of the image from a server needed for display on a screen.
This is used to reduce network traffic when viewing an image.
TIFF (Tagged Image File Format)
A common bitmap image format developed
by Aldus. TIFFs can be black-and-white, grayscale or color.
Tiling
Reproducing a large image by breaking
the image into parts, or tiles. When pieced together, they reproduce
the original image.
Tint
Some percentage of a solid ink.
Tints are created by using a screen to create the impression of a lighter
color when the ink is printed onto paper or another medium.
Toner
The material deposited on paper
or receiver in magnetic electrostatic (non-impact) printing.
Tracking
The adjustment of the overall
spacing between all text characters in a word or words.
Transfer Rate
The rate at which data can be
transferred, usually expressed as Kilobits per second (Kbps) or bytes
per second (Bps).
Transform
A color transformation from one
color file system (RGB to CMYK) to another, or changing from one hue
base to another.
Trapping
In offset printing, creating a
small area of overlap between different colored elements that come into
contact with one another on a printed piece to avoid any visible gaps
that might arise from slight mis-registration on press.
Trilinear Scanner
A scanning device that uses three
linear array charge coupled devices utilizing red, green and blue filters
to capture color scans in a single pass.
Tungsten
Metal in filament of bulbs creating
illumination when electronically charged. Tungsten= 3200 Kelvin an orange
color.
TWAIN
A standard application protocol
that allows cross-platform and multi-manufacturer communication from
the scanner to the software.
Tweening
Placing between or interpolating
the area between pixels.
24-bit Color
A digital color model that uses
eight bits each for the three additive colors red, green and blue; creating
more than 16 million colors.
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U
UCR (Under Color Reduction)
The removal of cyan, magenta and
yellow from neutral color areas (primarily shadow tones) and their replacement
with black. The reverse is UCA (Under Color Addition).
UCR (Undercolor Removal)
A type of process color separation
which determines the amount of black ink used to replace Cyan, Magenta,
and Yellow in areas where those three inks overlap.
Unix
A multi-tasking operating system
invented by AT&T and found in powerful computers developed by companies
such as Sun MicroSystems, Silicon Graphics, Hewlett-Packard and others.
It allows a computer to perform several intensely complex tasks at the
same time, even when it involves very large amounts of data, such as
would be found in commercial digital imaging environments.
Unsharp Masking (USM)
The sharpening of an image by
creating contrast at contrasting edges of the element.
UnZip
To decompress a file (usually
text) using PKUNZIP or WinZip, two popular programs. The decompression
takes place automatically when a Zip compressed file is opened (See
Zip).
URL (Uniform Resource Locator)
This is the address for a given
homepage or site on the World Wide Web. Each homepage has its own address
and is registered. Generally, a URL will appear like this: http://www.name.com.
The last three letters are called an extension: *.com = commercial;
*.org = organization; *.edu = educational institution; *.gov = government.
Other, less common extensions are also used.
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V
Vaporware
A term referring to "Not-Yet-Released"
software.
VAR (Value Added Retailer)
An equipment and software reseller
who puts together systems and often provides support services.
VDR (Video Disk Recorder)
A device that records to video
disk medium.
VRAM (Video Random Access Memory)
RAM that receives video display
data from the software and operating system, and transfers it to the
video display hardware.
Vector Image
A computer image that uses mathematical
descriptions of paths and fills to define the graphic, as opposed to
individual pixels.
VESA
A term used for a local bus.
VGA (Video Graphics Array)
A mid-level resolution video display
monitor.
Video Board
An expansion board that processes
video signals for display on the monitor.
Video Prints
A print made directly from video
output instead of from a computer RIP.
Vignette
A transition from one color or
intensity to another.
Virtual Memory
Using a hard drive as (RAM).
Virus
An malicious implant put into
software that can cause failures of systems such as data or memory loss.
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W
WAN (Wide Area Network)
A group of computers, LAN's or
servers interconnected for broad communications.
Wash
A term meaning to affect color
or tint by adding saturation or chroma.
Web Site
Any location on the World Wide
Web that can be linked to any other site.
White
The result of combining the additive
primary colors (Red, Green and Blue).
White Point
The lightest tone printable in
an image. All tone values above this threshold will print as white.
World Wide Web
A part of the internet that allows
text, pictures and graphics to be linked and used in a single graphical
user interface (GUI).
WORM (Write-Once Read Many
Times)
A storage device that uses a medium
that once written to can not be written over. Photo CD is an example.
Write
The act of creating, sending or
transferring data to an output device or storage.
WYSIWYG (What You See Is What
You Get)
A monitor configured to represent
the images displayed in a manner consistent with the desired printed
result. Pronounced "wizzy-wig."
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X
XA (Extended Architecture)
A specific type of compact disc
read only devices that are compatible with the Photo CD format and other
CD's. Multiple session Photo CD's cannot be fully utilized on non-XA
drives.
X-Windows
The Unix equivalent of Microsoft
Windows. Most Unix graphical user interfaces, such as Motif and OpenLook,
are based on X-Windows.
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Y
YCC
A color space developed by Eastman
Kodak to define colors by luminance (Y) and two levels of chrominance
(C and C).
Yellow
A subtractive primary color for
color printing and printing. It is made up of equal parts of red and
green projected light.
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Z
Zip
To compress a file (usually text)
using PKZIP or WinZIP, two popular programs. Commonly used to reduce
the size of a file to speed up transmission over the internet or an
on-line service.
Zip Drive
A relatively new removable storage
device employing a small disk similar in design to a floppy disk, but
offering significantly more storage space (approximately 100MB) and
speed.
Zoom
Making the image or image part
become larger (zooming in) or smaller (zooming out) as it appears on
the monitor.
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