Games of Daze/Infomagic - Games of Daze (Summer 1995) (Disc 1 of 2).iso/x2ftp/msdos/indeo/glossa.txt

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MULTIMEDIA:  A Glossary
May 14, 1992



We've assembled this glossary to help you understand Intel's meaning for
many of the following words and acronyms when you find them in our
materials.

Much information for this glossary came from four published sources.
All four are excellent publications, with more multimedia terminology
and definitions than has been included here.


Multimedia Applications Development Using DVI Technology, by Mark J.
Bunzel and Sandra K. Morris, McGraw Hill Book Company, New York, 1992.

Digital Video in the PC Environment, by Arch. C. Luther, McGraw-Hill
Book Company, New York, 1991.

Multimedia & Related Technologies:  A Glossary of Terms, published by
the editors of Multimedia and Videodisc Monitor at Monitor Information
Services, [phone].

The Video Compression Glossary, by Craig Birkmaier, Videography, June
1991. [phone].


A
ActionMedia(r)
DVI board and software product family, jointly developed with IBM.  An
Intel trademark.

active pixel region
On a computer display, the area of the screen used for actual display of
pixel information.

ADPCM
Adaptive Differential Pulse Code Modulation.  An encoding format for
storing audio information in a digital format.

adaptive compression
Data compression software that continually analyzes and compensates its
algorithm, depending on the type and content of the data and the storage
medium.

additive color
Color produced by "adding" colors, usually the combination of red,
green, and blue.

algorithm
In compression software refers to a specific formula used to compress or
decompress video.

aliasing
A form of image distortion associated with signal sampling.  A common
form of aliasing is a stair-stepped appearance along diagonal and curved
lines.

analog
The representation of numerical values by physical variables such as
voltage, current, etc.  Analog devices are characterized by dials and
sliding mechanisms.  See also digital.

analog video
A video signal that represents an infinite number of smooth gradations
between given video levels.  By contrast, a digital video signal assigns
a finite set of levels.  See also digital video.

anamorphic
Unequally scaled in vertical and horizontal dimensions.

antialiasing
A form of interpolation used when combining images; pixels along the
transitions between images are averaged to provide a smooth transition.

ANSI
American National Standards Institute.  A standards-setting,
non-government organization which develops and publishes standards for
voluntary use in the United States.

API
Application Programmers Interface.  Loosely used to describe the point
at which software modules or layers meet and interconnect.

artifact
An unintended, unwanted visual aberration in a video image.

ASCII
American Standard Code for Information Interchange.  The most popular
coding method used by small computers for converting letters, numbers,
punctuation, and control codes into digital form.

aspect ratio
The relationship of width and height.  When an image is displayed on
different screens, the aspect ratio must be kept the same to avoid
"stretching" in either the vertical or horizontal direction.

asymmetrical compression
A system which requires more processing capability to  compress an image
than to decompress an image.  It is typically used for
the mass distribution of programs on media such as CD-ROM, where
significant expense can be incurred for the production and compression
of the program, but the playback system must be low in cost.

audio
What a human can hear.  Audio frequencies range from 15Hz to 20,000Hz.

authoring system
Software which helps developers design interactive courseware easily,
without the painstaking detail of computer programming.

AVSS
Audio-Video Support System.  DVI system software for DOS.  It plays
motion video and audio.

AVK
Audio Video Kernel.  DVI system software designed to play motion video
and audio across hardware and operating system environments.

B
bandwidth
Usually used in context to refer to the amount of data/unit of time that
must move from one point to another - such as from CD-ROM to processor.

bit map
Representation of characters or graphics by individual pixels arranged
in row (horizontal) and column (vertical) order.  Each pixel can be
represented by either one bit (simple black and white) or up to 32 bits
(high definition color).

bit-mapped graphics
Images which are created with matrices of pixels, or dots.  Also called
raster graphics.

bit specifications
Number of colors or levels of gray that can be displayed at one time.
Controlled by the amount of memory in the computer's graphics controller
card.  An 8-bit controller can display 256 colors or levels of gray; a
16-bit controller, 64,000 colors; a 24-bit controller, 16.8 million
colors.

bpp
Bits Per Pixel.  The number of bits used to represent the color value of
each pixel in a digitized image.

bps
Bits Per Second.  The number of bits transferred in a data
communications system.  Measures speed.

brightness
The balance of light and dark shades in an image.

C
CCITT
Consultative Committee for International Telephone and Telegraph.  An
international standards organization dedicated to creating
communications protocols that will enable global compatibility for the
transmission of voice, data, and video across all computing and
telecommunications equipment.

CD
Compact Disc.  A standard medium for storaging digital data in
machine-readable form, accessible with a laser-based reader.

CD-I
Compact Disc-Interactive.  A compact disc format (developed by NV
Philips and Sony Corporation) which provides audio, digital data, still
graphics and limited motion video.

CD-ROM
Compact Disc-Read Only Memory.  A 4.75" laser-encoded optical memory
storage medium (developed by NV Philips and Sony Corporation) with the
same constant linear velocity (CLV) spiral format as compact audio discs
and some videodiscs.  CD-ROMs can hold about 550 megabytes of data.

CD-ROM XA
Compact Disc-Read Only Memory eXtended Architecture.  An extension of
the CD-ROM standard billed as a hybrid of CD-ROM and CD-I, and promoted
by Sony and Microsoft.  The extension adds ADPCM audio to permit the
interleaving of sound and video data to animation and with sound
synchronization.  It is an essential component of Microsoft's plan for
multimedia computers.

CDTV
Commodore Dynamic Total Vision.  Consumer multimedia system from
Commodore which includes CD-ROM/CD audio player, Motorola 68000
processor, 1MB RAM, and 10-key infrared remote control.

CGA
Color Graphics Adapter.  A low resolution video display standard,
invented for the first IBM PC.  CGA pixel resolution is 320x200.

CGM
Computer Graphics Metafile.  A standard format that allows for the
interchanging of graphics images.

chroma, chrominance
The color portion of the video signal that includes hue and saturation
information.  Requires luminance, or light intensity, to make it
visible.

CIE
Commission International de l'Eclairage.  The international commission
on illumination.  Developer of color matching systems.

CMYK
Cyan, Magenta, Yellow, and blacK.  The four process colors that are used
in four-color printed reproduction.

color cycling
A means of simulating motion in a video by changing colors.

color keying
To superimpose one image over another for special effects.

composite video
The complete visual wave form of the color video signal composed of
chromatic and luminance picture information; blanking pedestal; field,
line, and color sync pulses; and field equalizing pulses.

compound document
A file that has more than one element (text, graphics, voice, video)
mixed together.

compressed video
A digital video image or segment that has been processed using a variety
of computer algorithms and other techniques to reduce the amount of data
required to accurately represent the content - and thus, the space
required to store that content.

compression
The translation of data (video, audio, digital, or a combination) to a
more compact form for storage or transmission.

continuous tone
An image that has all the values (0 to 100%) of gray (black and white)
of color in it.  A photograph is a continuous tone image.

contrast
The range between the lightest tones and the darkest tones in an image.

convergence
In an RGB monitor, where red, green, and blue signals all "converge" in
one pixel.  At full brightness, the RGB pixel in convergence would be
white.

CSC
Computer Support Collaboration.  Describes computers that enhance
productivity when working in groups.  Application examples include video
conferencing, video mail, and shared workspaces.

D
DAT
Digital Audio Tape.  A consumer recording and playback media for high
quality audio.

data rate
The speed of a data transfer process, normally expressed in bits per
second or bytes per second.

DCT
Discrete Cosine Transform.  A form of coding used in most of the current
image compression systems for bit rate reduction.

decompression
To reverse the procedure conducted by compression software, and thereby
return compressed data to its original size and condition.

density
The degree of darkness of an image.  Also, percent of screen used in an
image.

delivery system
The equipment used by end users to run or "play" on interactive program.

device driver
Software that tells the computer how to talk to a peripheral device,
such as a videodisc player or printer.

digital
A method of signal representation by a set of discrete numerical values,
as opposed to a continuously fluctuating current or voltage.  See also
analog.

digital video
A video signal represented by computer-readable binary numbers that
describe a finite set of colors and luminance levels.  See analog video.

digitization
Process of transforming analog video signal into the digital
information.

DVI(r)
Intel's brand name for a variety of digital video and audio products.
Current product families include the i750(r) video processor,
ActionMedia(r) II boards, AVK and AVSS system software, and PLV, RTV and
JPEG algorithms.  Future versions of the i750 video processor will
support Px64 and MPEG motion video standards.  An Intel trademark.

E
EGA
Enhanced Graphics Adapter.  A display technology for the IBM PC.  It's
been replaced by VGA.  EGA pixel resolution is 640x350.

encoding
The process of creating a compressed file.

F
field
One-half of a complete video frame, consisting of every other analog
scan line.

filtering
A process used in both analog and digital image processing to reduce
bandwidth.  Filters can be designed to remove information content such
as high or low frequencies, for example, or to average adjacent pixels
creating a new value from two or more pixels.

fractals
Along with rastor and vector graphics, a way of defining graphics in a
computer.  Fractal graphics translate the natural curves of an object
into mathematical formulas, from which the image can be later
constructed.

frame
A single, complete picture in a video or film recording.  A video frame
consists of two interlaced fields of either 525 lines (NTSC) or 625
lines (PAL/SECAM), running at 30 frames per second (NTSC) or 25 fps
(PAL/SECAM).  Film runs at 24 fps.

frame grabber
A device that "captures" and potentially stores one complete video
frame.  Also known as frame storer.

frame rate
The speed at which video images are displayed.

full-motion video
Video reproduction at 30 frames per second (NTSC-original signals) or 25
frames per second (PAL-original signals).

G
gain
The increase in signaling power as an audio signal is boosted by an
electronic device.  It's measured in decibels.

gradient
In graphics, having an area smoothly blend from one color to another, or
from black to white, or vice versa.

gray scale
The spectrum, or range, of shades of black an image has.

H
HDTV
High Definition TV.  A proposed standard, recommending the doubling of
current 525 lines per picture to 1050 lines, and increasing the screen
aspect ratio (width:height) from the current 12:9 to 16:9, which would
create a television screen shaped more like a movie screen.

high resolution
An adjective describing improvement in image quality as a result of
increasing the number of pixels per square inch.  Called hi-res for
short.

High Sierra format
A standard format for placing files and directories on CD-ROM, revised
and adopted by the International Standards Organization as ISO 9660.

HSB
Hue Saturation Brightness.  With the HSB model, all color can be defined
by expressing their levels of hue (the pigment), saturation (the amount
of pigment) and brightness (the amount of white included), in
percentages.

Hz
Abbreviation for Hertz; cycles per second.

I
i750(r)
Name of the programmable video processor family from Intel.  An Intel
trademark.

IMA
Interactive Multimedia Association.  Formed in 1991 (rooted in IVIA,
Interactive Video Industry Association), industry association chartered
with creating and maintaining standard specifications for multimedia
systems.

image
The computerized representation of a picture or graphic.

image resolution
The fineness or coarseness of an image as it was digitized, measured in
Dots Per Inch (DPI), typically from 200 to 400 DPI.

interactive video
The fusion of video and computer technology.  A video program and a
computer program running in tandem under the control of the user.  In
interactive video, the user's actions, choices, and decisions genuinely
affect the way in which the program unfolds.

interlace
Scheme to display a video image by displaying alternate scan lines in
two discrete fields.

ISO
International Standards Organization.  Worldwide group responsible for
establishing and managing various standards committees and expert
groups, including several image compression standards.

ISV
Independent Software Vendor.  Company which develops and sells
application tools and/or software titles.

interframe coding
Compression techniques which track the differences between frames of
video.  Results in more compression over a range of frames than
intraframe coding.

interpolation
The process of averaging pixel information when scaling an image.  When
reducing the size of an image, pixels are averaged to create a single
new pixel; when an image is scaled up in size, additional pixels are
created by averaging pixels of the smaller image.

intraframe coding
Compression within each frame individually.  Results in less compression
over a range of frames than interframe coding.

J
JPEG
Joint Photographic Experts Group.  A working committee under the
auspices of the International Standards Organization (ISO) that is
attempting to define a proposed universal standard for the digital
compression and decompression of still images for use in computer
systems.

L
LAN
Local Area Network.

lossless compression
Ensures that the original data is exactly recoverable with no loss in
image quality.

lossy compression
The original data is not completely recoverable.  Although image quality
may suffer, many experts believe that up to 95 percent of the data in a
typical image may be discarded without a noticeable loss in apparent
resolution.

luminance
Brightness; one of the three image characteristics coded in composite
television (represented by the letter Y).  May be measured in lux or
foot-candles.

M
MAN
Metropolitan Area Network.

MCA
Media Control Architecture.  System-level specification developed by
Apple Computer for addressing various media devices (videodisc/videotape
players, CD players, etc.) to its Macintosh computers.

MCI
Media Control Interface.  Platform-independent multimedia specification
(published by Microsoft and others in 1990) that provides a consistent
way to control devices such as CD-ROMs and video playback units.

Micro Channel
Personal computer bus architecture introduced by IBM in some of its PS/2
series microcomputers.  Incompatible with original PC/AT (ISA)
architecture.

MIDI
Musical Instrument Digital Interface.  An industry-standard connection
for computer control of musical instruments and devices.

MIPS
Millions of Instructions Per Second.  Refers to a computer processor's
performance.

MOPS
Millions of Operations Per Second.  In the case of DVI technology, more
MOPS translate to better video quality.  Intel's video processor can
perform multiple video operations per instruction, thus the MOPS rating
is usually greater than the MIPS rating.

MPEG
Motion Picture Experts Group.  A working committee under the auspices of
the International Standards Organization (ISO) that is attempting to
define standards for the digital compression and decompression of motion
video/audio for use in computer systems.  The first phase of the
committee's activity is addressing methods for encoding video within the
1.5 Mbit/second CD-ROM data rate.

multimedia
Refers to the delivery of information which combines different content
formats (motion video, audio, still images, graphics, animation, text,
etc.).

multimedia computing
Refers to the delivery of multimedia information delivered via
computers.

N
NLM
Network Loadable Module.

NOS
Network Operating System.

NTSC
National Television Systems Committee of the Electronics Industries
Association (EIA) that prepared the standard of specifications approved
by the Federal Communications Commission, in December 1953, for
commercial color broadcasting.  NTSC is still the TV standard for the
U.S. and Japan, et. al - (See NTSC format).

NTSC format
A color television format having 525 scan lines; a field frequency of 60
Hz; a broadcast bandwidth of 4 MHz; line frequency of 15.75 KHz; frame
frequency of 1/30 of a second; and a color subcarrier frequency of
3.58MHz.  See also PAL, SECAM.

O
OEM
Original Equipment Manufacturer.  Company which develops, produces and
sells computer and consumer hardware.

P
Px64
Also known as CCITT Recommendation H.261.  A draft standard for motion
video compression in videophone and teleconferencing applications,
designed around 64 kbit/second transmission channels.  DVI technology's
next generation video processor will support Px64.

PAL format
Phase Alternation Line; the European video standard, except for France.
See also NTSC, SECAM.

PCM
Pulse Code Modulation.  The most common method of encoding an analog
signal into a digital bit stream.  A digitization technique, not a
universally accepted standard.

pixels
An abbreviation for picture element.  The minimum raster display
element, represented as a point with a specified color or intensity
level. One way to measure picture resolution is by the number of pixels
used to create images.

PLV
Production Level Video -  Highest quality DVI motion video compression
algorithm today.  Compression is achieved "off-line", (non-real-time),
while playback (decompression) is real-time (asymmetrical compression).
Independent of the technology in use, off-line compression will always
produce a better image quality than real-time or symmetrical compression
since more time and processing power is used per frame.

R
raster graphics
Images defined as a set of pixels or dots in a column-and-row format.
Also called bit-mapped graphics.

real-time
In computing, refers to an operating mode under which data is received,
processed and the results returned instantaneously.

resolution
Number of pixels per unit of area.  A display with a finer grid contains
more pixels and thus has a higher resolution, capable of reproducing
more detail in an image.

RGB
Red-Green-Blue.  A type of computer color display output signal
comprised of separately controllable red, green, and blue signals; as
opposed to composite video, in which signals are combined prior to
output.  RGB monitors typically offer higher resolution than composite.
See also composite video.

RIFF
Resource Interchange File Format.  Platform-independent multimedia
specification (published by Microsoft and others in 1990) that allows
audio, image, animation, and other multimedia elements to be stored in a
common format.  See also Media Control Interface (MCI).

RTV
Real Time Video.  On-line, symmetrical, 30 frames per second, DVI motion
video compression algorithm.

S
sampling
The first step in the process of converting an analog signal into a
digital representation.  This is accomplished by measuring the value of
the analog signal at regular intervals called samples.  These values are
then encoded to provide a digital representation of the analog signal.

saturated colors
Strong, bright colors (particularly reds and oranges) which do not
reproduce well on video; they tend to saturate the screen with color or
bleed around the edges, producing a garish, unclear image.

scalability
The ability to vary the information content of a program by changing the
amount of data that is stored, transmitted or displayed.  In a video
image, this translates into creating larger or smaller windows of video
on screens (shrinking effect).

scaling
Process of uniformly changing the size of characters or graphics.

SECAM format
"SEquential Couleur A Memoire" (sequential color with memory), the
French color TV system also adopted in Russia.  The basis of operation
is the sequential recording of primary colors in alternate lines.  See
also NTSC, PAL.

SMPTE time code
An 80-bit standardized edit time code adopted by SMPTE, the Society of
Motion Picture and Television Engineers.  See time code.

Subsampling
Bandwidth reduction techniques which reduce the amount of digital data
used to represent an image, part of a compression process.

S-video
Type of video signal used in the Hi8 and S-VHS videotape formats.  It
transmits luminance and color portions separately, using multiple wires,
thus avoiding the NTSC encoding process and its inevitable loss of
picture quality.  Also known as Y/C video.

symmetrical compression
A compression system which requires equal processing capability for
compression and decompression of an image.  This form of compression is
used in applications where both compression and decompression will be
utilized frequently.  Examples include:  still image databasing, still
image transmission (color fax), video production, video mail,
videophones, and videoconferencing.  See asymmetrical compression.

T
teleconference
A general term for a meeting not held in person.  Usually refers to a
multi-party telephone call, set up by the phone company or private
source, which enables more than two callers to participate in a
conversation.  The growing use of video allows participants at remote
locations to see, hear, and participate in proceedings, or share visual
data ("video conference").

TIFF
Tagged Image File Format.  A bit map file format for describing and
storing color and gray scale images.

time code
A frame-by-frame address code time reference recorded on the spare track
of a videotape or inserted in the vertical blanking interval.  It is an
eight-digit number encoding time in hours, minutes, seconds, and video
frames (e.g.: 02:04:48:26).

tint
Another name for hue.

trichromatic
The technical name for RGB representation of color to create all the
colors in the spectrum.

V
VAR
Value Added Reseller.  A company which resells hardware and software
packages to developers and/or end-users.

VCR
Video Cassette Recorder.  An analog magnetic recording and playback
machine.  Generally used for recording and viewing full-motion video;
also useful as a data backup device.

VDRV
Variable Data Rate Video.  In digital systems, the ability to vary the
amount of data processed per frame to match image quality and
transmission bandwidth requirements.  DVI symmetrical and asymmetrical
systems can compress video at variable data rates.

vector graphics
Images defined by sets of straight lines, defined by the locations of
the end points.

VESA
Video Electronics Standards Association.

VGA
Video Graphics Array.  Standard IBM video display standard.  Provides
medium-resolution text and graphics.  VGA pixel resolution is 640x480.

W
WAN
Wide Area Network.

X
XGA
EXtended Graphics Adapter.  New IBM graphics standard that includes VGA
and supports higher resolutions, up to 1024 pixels by 768 lines
interlaced.

Y
YUV color system
A color encoding-scheme for natural pictures in which the luminance and
chrominance are separate.  The human eye is less sensitive to color
variations than to intensity variations, so YUV allows the encoding of
luminance (Y) information at full bandwidth and chrominance (UV)
information at half bandwidth.




ActionMedia, DVI and i750 are registered trademarks of Intel Corp.