| Name |
Description |
| 16x9 |
A wide screen television format in which the aspect ratio of the
screen is 16 units wide by 9 high as opposed to the 4x3 of normal
TV. |
| 24-bit color |
Color for which each red, green, and blue component stores 8 bits of
information. 24-bit color is capable of representing over one million
different variations of color. |
| 2:3 pulldown |
See pulldown. |
| 2K |
An image scanned into a computer file at a resolution of 2048
horizontal pixels. |
| 3:2 pulldown |
The technique used to convert 24 frames per second film to 30 frames
per second video. Every other film frame is held for 3 video fields
resulting in a sequence of 3 fields, 2 fields, 2 fields, etc. |
| 4 fsc |
Composite Digital video as used in D2 and D3 VTRs. Stands for 4 times
the Frequency of Subcarrier, which is the sampling rate used. |
| 4:2:2 |
The sampling ratio used in the D1 (CCIR 601) digital video signal. For
every 4 samples of luminance there are 2 samples each of R-Y (Red minus
Luminance) and B-Y (Blue minus luminance). |
| 4:3 |
The aspect ratio of conventional video, television, and computer
screens. |
| 4:4:4 |
A sampling ratio that has equal amounts of the luminance and both
chrominance channels. |
| 4K |
An image scanned into a computer file at a resolution of 4096 pixels.
4 K is considered to be a full-resolution scan of 35mm film. |
| 8mm |
A compact videocassette format that uses magnetic tape and is eight
millimeters wide. 8mm is a world-wide standard and offers high-quality
recording and playback of video and audio. |
| A and B cutting |
A method of assembling original material in two separate rolls,
allowing optical effects to be made by double printing ( A and B
Printing). |
| a-frame edit |
A video edit which starts on the first frame of the 5 video frame (4
film frame) sequence created when 24 frame film is transferred to 30 frame
video (see 3:2 pulldown). The A-frame is the only frame in the sequence
where a film frame is completely reproduced on one complete video frame.
Here is the full sequence (The letters correspond to film frames.)
A-frame=video fields 1&2, B-frame= video fields 1&2&1,
C-frame=video fields 2&1, D-frame=video fields 2&1&2. |
| A-mode |
A linear method of assembling edited footage. In A-mode, the editing
system performs edits in the order in which they will appear on the
master, stopping whenever the edit decision list (EDL) calls for a tape
that is not presently in the deck. See also B-mode, C-mode, D-mode,
E-mode, source mode. |
| a-mode edit |
An editing method where the footage is assembled in the final scene
order. Scene 1, scene 2, ... |
| A-roll |
A method of conforming that requires the compositing of all multilayer
effects into a single layer (including laboratory-standard dissolves and
fades) before assembly. Also called single-strand editing. |
| A-to-D converter |
An electronic device that converts analog signals to digital. An
A-to-D converter is an integral part of digital-video-related
technology. |
| A/B roll |
Typically, A/B roll is an editing technique where scenes or sounds on
two source reels (called roll A and roll B) are played simultaneously to
create dissolves, wipes, and other effects. On nonlinear editing systems,
A/B roll refers to using two source streams (.avi, .wav, .tga, and so on)
to create an effect. |
| A/B-roll linear editing |
Recording edits from two video sources, such as two VCRs to a third,
to achieve transition effects. See also, B-roll |
| A/D converter |
Analog-to-digital converter. A device that transforms a continuously
variable (analog) signal to discrete binary bits that represent digital
samples of the original signal. |
| A/V drive |
Audio/video drive; a high-end hard drive capable of storing
high-bandwidth (i.e., high data rate) audio/video data. |
| AC'97, AC'98 |
These are definitions by Intel for the audio I/O implementation for
PCs. Two chips are defined: an analog audio I/O chip and a digital
controller chip. The digital chip will eventually be replaced by a
software solution. The goal is to increase the audio performance of PCs
and lower cost. |
| AC Coupled |
AC coupling passes a signal through a capacitor to remove any DC
offset, or the overall voltage level that the video signal "rides" on. One
way to find the signal is to remove the DC offset by AC coupling, and then
do DC restoration to add a known DC offset (one that we selected). Another
reason AC coupling is important is that it can remove large (and harmful)
DC offsets. |
| academy |
Pertaining to specifications that meet the Academy of Motion Picture
Arts and Sciences standards, such as academy leader, academy format (for
film stock), academy countdown, and so forth. |
| access time |
The length of time it takes to find, retrieve, and display digital
information. |
| active picture area |
The part of a TV picture that contains actual picture as opposed to
sync or other data. Vertically the active picture areas is 487 lines for
NTSC and 576 lines for PAL. The inactive areas is called blanking. |
| ADC, A/D |
Analog-to-Digital Converter. This device is used to digitize audio and
video. An ADC for digitizing video must be capable of sampling at 10 to
150 million samples per second (MSPS). |
| add edit |
An edit added between consecutive frames in a sequence segment within
the Timeline. An add edit separates segment sections so the user can
modify or add effects to a subsection of the segment. |
| additive colour |
Colour mixture by the addition of light of the three primaries, red,
green, and blue. |
| additive mix |
A mixing process that adds the colour value of a pixel in one source
clip to the value of a corresponding pixel in a second source clip, and
assigns the resulting value to the corresponding pixel in the output
clip. |
| ADR |
1. Automatic display replacement. The process of looping playback of a
selected region in a sequence and automatically recording multiple
replacement takes. 2. Automatic dialog replacement in film. Also called
dubbing |
| advance |
The separation between a point on the sound track of a film and the
corresponding picture image. |
| Advanced Television Systems Committee (ATSC) |
The group that recommended the new digital television standards to the
FCC. They defined the SDTV and HDTV standards for the United States, using
MPEG-2 for video and Dolby Digital for audio. Other countries are also
adopting the ATSC HDTV standard. |
| AES |
Audio Engineering Society. The primary international organization of
users and producers of professional audio. The AES maintains a standards
committee that supervises the work of several subcommittees and working
groups covering various fields of sound reinforcements. |
| AES/EBU |
The digital audio standard set by the Audio Engineering Society and
European Broadcast Union and used by most forms of digital audio from CDs
to D1. |
| AFM |
Abbreviation for audio frequency modulation; the most common form of
audio recording found in most consumer and professional video recording
decks, especially in VHS and 8mm recorders. AFM audio is limited in
dynamic range and frequency response, and can include stereo and
multi-track audio. |
| AIFF |
Audio Interchange File Format. This is the format for both compressed
and uncompressed audio data. |
| AIFF-C |
Audio Interchange File Format-Condensed. A sampled-sound file format
that allows for the storage of audio data. This format is primarily used
as data interchange format but can be used as a storage format as well.
OMF Interchange includes AIFF-C as a common interchange format for
noncompressed audio data. |
| aliasing |
Defects in the picture caused by too low a sampling frequency or poor
filtering. Usually seen as "jaggies" or stair steps in diagonal
lines. |
| alpha channel |
The fourth channel of a 32-bit RGB image that creates transparency in
the image. The other three channels are red, green, and blue. |
| Alpha Mix |
This is a way of combining two images. How the mixing is performed is
provided by the alpha channel. The little box that appears over the
left-hand shoulder of a news anchor is put there by an alpha mixer.
Wherever the little box is to appear, a "1" is put in the alpha channel.
Wherever it doesn't appear, a "0" is used. When the alpha mixer sees a "1"
coming from the alpha channel, it displays the little box. Whenever it
sees a "0", it displays the news anchor. Of course, it doesn't matter if a
"1" or a "0" is used, but you get the point. |
| ambient |
Natural, or surrounding light in a clip. |
| American Standard Code for Information Interchange, (ASCII) |
Unformatted text characters that are interchangeable across platforms
and applications. Also referred to as "plain text". |
| Ampex Digital Optics, (ADO) |
Trade name for digital effects system manufactured and sold by
Ampex. |
| amplitude |
The maximum distance an oscillating body (e.g., a pendulum) or wave
travels from a mean point. |
| Amplitude Modulation, (AM) |
A method of encoding data onto a carrier, such that the amplitude of
the carrier is proportional to the data value.
|
| analog |
Analog information is represented electronically as a continuously
varying electronic signal. |
| analog recording |
The common form of magnetic recording where the recorded waveform
signal maintains the shape of the original waveform signal. All videotape
source footage is analog. When recorded or digitized (via telecine
transfer), footage is converted from the analog format to a digital
format. |
| analog video |
A video signal made of a continuous electrical signal. Your television
and VCR can be analog video devices. To be stored and manipulated on a
computer, analog video must be converted to digital video. |
| anamorphic |
Distortion in viewing of images or geometry related to the difference
between computer monitor screen aspect ratio (in which pixels are square)
and broadcast, projected or frame aspect ratio (in which image pixels are
wider than they are high). |
| Ancillary Timecode, (ATC) |
BT.1366 defines how to transfer VITC and LTC as ancillary data in
digital component interfaces. |
| animatic |
Limited animation consisting of art work shot and edited to serve as a
video tape storyboard. Commonly used for test commercials. |
| animation |
The recording of a sequence of still artwork or objects in a way that
makes them appear to move on film or video. 24 fps is considered the
appropriate speed for animation. |
| animation curve |
A curve depicting the interpolation between the various
keyframes. |
| answer |
Smoothing, removing, or reducing jagged edges along the lines and
curves in text, images, or geometry. |
| answer print |
The first print combining picture and sound submitted by the
laboratory for the customers' approval. |
| Anti-Alias Filter |
A lowpass filter used to bandwidth-limit a signal to less than
one-half the sampling rate. |
| anti-aliasing |
A technique that smooths jagged edges in computer-generated text or
graphics. The manipulation of edges (e.g., those between areas with
contrasting colors) in an image, graphic, or text to make the edges appear
smoother. Anti-aliased edges appear blurred up close but smooth at normal
viewing distance. Anti-aliasing is important when working with
high-quality graphics for television use. Contrast with aliasing. |
| aperture |
The opening which allows light to pass through a camera lens. An
adjustable diaphragm is used to control the size of the opening.
Effective Aperture
An adjustable diaphragm is used to control the
size of the opening. The apparent diameter of a lens viewed from the
position of the object against a diffusely illuminated background, such as
a sky.
Picture Aperture
The rectangular opening in a metal plate at
which each frame of the motion picture film is situated during exposure,
printing or projection.
Relative aperture
The ratio of the focal length of a lens to
its effective aperture for an object located at infinity. |
| Aperture Delay |
Aperture delay is the time from an edge of the input clock of the ADC
until the time the ADC actually takes the sample. The smaller this number,
the better. |
| Aperture Jitter |
The uncertainty in the aperture delay. This means the aperture delay
time changes a little bit each time, and that little bit of change is the
aperture jitter. |
| architecture |
In digital video, architecture (sometimes also known as format) refers
to the structure of the software responsible for creating, storing, and
displaying video content. A architecture may include such things such as
compression support, system extensions, and browser plug-ins. Different
multimedia architectures offer different features and compression options,
and store video data in different file formats. QuickTime, RealVideo, and
MPEG are examples of video architectures (though MPEG is also a type of
compression). |
| Artifacts |
A side effect in video or audio caused by signal processing. In the
video domain, artifacts are blemishes, noise, snow, spots, whatever. When
you have an image artifact, something is wrong with the picture from a
visual standpoint. Don't confuse this term with not having the display
properly adjusted. For example, if the hue control is set wrong, the
picture will look bad, but this is not an artifact. An artifact is some
physical disruption of the image. |
| ASA |
Exposure Index or speed rating that denotes the film sensitivity,
defined by the American National Standards Institution. Actually defined
only for black-and-white films, but also used in the trade for colour
films. |
| Aspect Ratio |
The ratio of the width of the picture to the height. Displays commonly
have a 4:3 or 16:9 aspect ratio. Program material may have other aspect
ratios (such as 20:9), resulting in it being "letterboxed" on the
display. |
| aspect ratio |
The numerical ratio of a viewing area's width to its height. In video
and television, the standard aspect ratio is 4:3, which can be reduced to
1.33:1 or simply 1.33. HDTV video format has an aspect ratio of 16:9. In
film, some aspect ratios include: 1.33:1, 1.85:1, and 2.35:1. |
| assemble edit |
Adding material that has a different signal to the end of a
pre-recorded section of a video tape. Adding an assemble edit to the
middle of an existing segment causes an abrupt and undesirable change in
the sync of the video signal. Contrast with insert edit. |
| asynchronous |
When digital communication (e.g., that between computers) is not
synchronized by a mutual timing signal or clock.Refers to circuitry
without a common clock or timing signal. |
| ATM |
Asynchronous transfer mode. A network technology based on transferring
data in packets of a fixed size. The packet used with ATM is relatively
small compared to units used with older technologies. The small, constant
packet size allows ATM equipment to transmit video, audio, and computer
data over the same network and ensures that no single type of data ties up
the line. Current implementations of ATM support data transfer rates of 25
to 622 Mb/s (megabits per second). This compares to a maximum of 100 Mb/s
for Ethernet, the current technology used for most local area networks
(LANs). |
| ATR |
Audiotape recorder. A device for recording and reproducing sound on
magnetic recording tape. |
| ATSC |
Advanced Television Systems Committee. They defined the SDTV and HDTV
standards for the United States, using MPEG-2 for video and Dolby Digital
for audio. Other countries are also adopting the ATSC HDTV
standard. |
| ATSC A/49 |
Defines the ghost cancellation reference signal for NTSC. Download the
specification. |
| ATSC A/52 |
Defines the (Dolby Digital) audio compression for ATSC HDTV. Download
the specification. |
| ATSC A/53, A/54 |
Defines ATSC HDTV for the USA. Download the A/53 and A/54
specifications. |
| ATSC A/57 |
Defines the program, episode, and version ID for ATSC HDTV. Download
the specification. |
| ATSC A/63 |
Defines the method for handling 25 and 50 Hz video for ATSC HDTV.
Download the specification. |
| ATSC A/65 |
Defines the program and system information protocol (PSIP) for ATSC
HDTV. Download the specification. |
| ATSC A/70 |
Defines the conditional access system for ATSC HDTV. Download the
specification. |
| ATSC A/90 |
Defines the data broadcast standard for ATSC HDTV. Download the
specification. |
| ATSC A/92 |
Defines the IP multicast standard for ATSC HDTV. Download the
specification. |
| attenuation |
A decrease in an electrical signal's amplitude. |
| Attic folder |
The folder containing backups of your files or bins. Every time you
save or the system automatically saves your work, copies of your files or
bins are placed in the Attic folder, until the folder reaches the
specified maximum. The Attic folder copies have the file name extension
.bak and a number added to the file name. The number of backup files for
one project can be changed (increased or decreased) in the Bin Settings
dialog box. |
| attribute clip |
A mechanism that applications can use to store supplemental
information in a special track that is synchronized to the other tracks in
a track group. |
| audio effects board |
Similar to a switcher, an audio effects board is the primary router
and mixer for source audio, and for adjusting, mixing, and filtering
audio. Usually, a digital audio workstation is used to perform more
complex audio work. |
| Audio Modulation |
Refers to modifying an audio subcarrier with audio information so that
it may be mixed with the video information and transmitted. |
| audio scrub |
See scrubbing. |
| Audio Subcarrier |
A specific frequency that is modulated with audio data. |
| audio subframe |
There are 100 subframes of audio for every frame of video. |
| audio sweetening |
The mixing of sound effects, music, and announcer audio tracks with
the audio track of the edited master tape, usually during the mixing
stages of a production. Also called audio postproduction for
video. |
| audio timecode |
Longitudinal timecode (LTC) recorded on an audio track. |
| AudioVision |
A registered trademark of Avid Technology, Inc. A digital, nonlinear
audio editing system that locks digital video in sync with audio for audio
editing and sweetening. |
| auto-assembly |
The automatic assembling of an edited video tape on a computerized
editing system (controller), based on an edit decision list (EDL).
Auto-assembly is used in assemble editing. |
| Automatic Frequency Control (AFC) |
A technique to lock onto and track a desired frequency. |
| Automatic Gain Control, (AGC) |
A circuit that automatically adjusts audio or video input
levels. |
| AutoSave |
A feature that saves your work at intervals you specify. Backups are
placed in the Attic folder. |
| AUX |
Auxiliary track. In a video editing system, a channel reserved for
connecting an external audio device, video device, or both. |
| AV |
Abbreviation for audiovisual; the making use of or relating to both
hearing and sight and to electronic media in general. |
| AVI |
Abbreviation for Audio-Video Interleaved; the algorithm created by
Microsoft for synchronizing and compressing analog audio and video
signals. AVI is also the file format used by Video for Windows |
| Avid disk |
The disk on the Macintosh platform that contains the operating system
files. The computer needs operating system information in order to
run. |
| Avid Projects folder |
The folder containing your projects. |
| AVR |
Avid Video Resolution. The compression level at which visual media is
stored by the Avid system. The system creates media in a particular AVR
using proprietary conversion algorithms to convert analog video to digital
form. |
| axis |
the component of an object that you use to determine its two or three
dimensional space and movement. |
| B'-Y' |
The blue-minus-luma signal, also called a color difference signal.
When added to the luma (Y') signal, it produces the blue video
signal. |
| b-frame |
Bi-directional frame. The frame in an MPEG sequence created by
comparing the difference between the current frame and the frames before
and after it. |
| B-mode |
"A ""checkerboard"" or nonsequential method of assembly. In B-mode,
the edit decision list (EDL) is arranged by source tape number. The edit
system performs all edits from the tapes currently assigned to decks,
leaving gaps that will be filled by material from subsequent reels. See
also A-mode, C-mode, D-mode, E-mode, source mode. " |
| b-mode edit |
An editing method where the footage is assembled in the order it
appears on the source reels. Missing scenes are left as black holes to be
filled in by a later reel. Requires fewer reel changes and generally
results in a faster edit session. |
| B-roll |
Refers to secondary or duplicated footage of a fill or secondary
nature usually played from the B source player in an A/B-roll linear
editing system. B roll does not refer to all tapes played from the B
source player. |
| backplane |
PCB (printed circuit board) on a Movie-2 bus connector. |
| backtiming |
A method of calculating the IN point by subtracting the duration from
a known OUT point so that, for example, music and video or film end on the
same note. |
| backup |
A duplicate copy of a file or disk in another location if the original
file or disk becomes corrupted. See also Attic folder. |
| balanced cable |
In audio systems, typically refers an a specific cable configuration
that cancels induced noise. |
| Bandpass Filter |
A circuit that allows only a selected range of frequencies to pass
through. |
| Bandwidth (BW) |
The range of frequencies a circuit will respond to or pass through. It
may also be the difference between the highest and lowest frequencies of a
signal. |
| Bandwidth Segmented Orthogonal Frequency Division Multiplexing |
BST-OFDM attempts to improve on COFDM by modulating some OFDM
carriers differently from others within the same multiplex. A given
transmission channel may therefore be "segmented", with different segments
being modulated differently. |
| bar code |
A pattern of vertical stripes of varying width and spacing that
encodes information. Bar codes can be used to encode timecode on
film. |
| base board |
Printed circuit board (and mounted components such as integrated
cirucuits, etc.) that is inserted into the computer's expansion slot. A
module board isoften attached to the base board. |
| Baseband |
When applied to audio and video, baseband means an audio or video
signal that is not modulated onto another carrier (such as RF modulated to
channel 3 or 4 for example). In DTV, baseband also may refer to the basic
(unmodulated) MPEG stream. |
| batch capture |
The automated process of capturing clips in a list. (see batch
list) |
| batch digitize |
The automated process in which groups of clips, sequences, or both are
digitized (recorded digitally). |
| batch list |
A list of clips to be batch captured. |
| batch record |
The automated process in which groups of clips, sequences, or both are
digitized (recorded digitally). |
| baud |
The number of electrical oscillations that occur each second. Baud was
the prevalent measure for bandwidth or data transmission capacity, but bps
(bits per second) is used most often now and is more accurate. |
| BBC |
British Broadcasting Corporation. |
| beam |
the directed flow of bombarding electrons in a TV picture tube. |
| beam-splitter prism |
The optical block in a video camera onto which three CCD sensors are
mounted. The optics split the red, green and blue wavelengths of light for
the camera. |
| Bento |
A registered trademark of Apple Computer, Inc. A general container
format and software API (application programming interface). Bento is used
by OMF Interchange as a storage and access system for the information in
an OMF Interchange file. |
| best light |
A telecine transfer performed with optimum settings of the color grade
controls but without precise scene-by-scene color correction. |
| Betacam, Betacam SP |
Trademarks of Sony Electronics, Inc. Two component videotape and video
recording standards. Sony Betacam was the first high-end cassette-based
system, recording video onto 1/2-inch magnetic tape. The SP version
arrived 3 years after the first Betacam, improving on signal-to-noise
ratios, frequency responses, the number of audio channels, and the amount
of tape available on cassettes. SP is now the only type sold. |
| bezier |
A curve that connects the vertices of a polygon; each vertex has two
tangents, or handles, which you can use to adjust the slope of the
adjacent curve or side of a polygon. |
| bi-phase |
Electrical pulses from the tachometer of a telecine, used to update
the film footage encoder for each new frame of film being
transferred. |
| bicubic surface |
A surface that you can add to a layer with four control handles that
you can use for four-point tracking. |
| bid sheet |
A written estimate, or quote, for video or production services. |
| bilinear surface |
A surface that you can add to a layer with more than four control
handles for creating non-linear effects. |
| bin |
A database in which master clips, subclips, effects, and sequences are
organized for a project. Bins provide database functions to simplify
organizing and manipulating material for recording, digitizing, and
editing. |
| BIOS |
Basic Input/Output System settings for system components, peripherals,
etc. This information is stored in a special battery-powered memory an is
usually accessible for changes at computer start-up. |
| bit |
One binary digit. An eight-bit byte can define 256 brightness or
colour values. |
| bit rate |
The amount of data transported in a given amount of time, usually
defined in Mega (million) bits per second (Mbps). Bit rate is one means
used to define the amount of compression used on a video signal.
Uncompressed D1 has a bit rate of 270 Mbps. Mpeg 1 has a bit rate to 1.2
Mbps. HDTV has a bit rate of 1.5Gbps (giga bits per second). |
| bit stream |
A continuous series of bits, commonly used to describe a large file
such as MPEG video that is read as a stream instead of all at once. |
| BITC |
Burned-In Time Code. The timecode information is displayed within a
portion of the picture, and may be viewed on any monitor or
TV. |
| bitmap |
A pixel-by-pixel description of an image. Bitmap images are also
referred to as raster images. |
| black and code |
Video black, timecode, and control track that are prerecorded onto
videotape stock. Tapes with black and code are referred to as striped or
blacked tapes. |
| black box |
A term used to describe a piece of equipment dedicated to one specific
function. |
| black burst |
A video signal that has no luminance or chrominance components (except
burst) but contains all the other elements of a video signal. Black burst
is the reference signal commonly used for timing audio and video samples.
An electronic device that emits a signal that registers as pure black when
recorded on videotape. |
| black edits |
1. A video source with no image. 2. A special source you can fade
into, out of, or use for other effects. |
| Black Level |
This level represents the darkest an image can get, defining what
black is for a particular video system. If for some reason the video goes
below this level, it is referred to as blacker-than-black. You could say
that sync is blacker-than-black. |
| black point |
The luminance value in a video image that you set to be equal to
reference black when making a color adjustment. Compare with white
point. |
| black stripe |
See striping. |
| blacked tapes |
See black and code. |
| blackout |
The fading of a video signal to black to indicate, for example, the
end of a show. |
| blanket fee |
Typically used for musical selections. One who pays a blanket fee has
permission to use the musical selection the fee covers in an unlimited
number of released projects and videos. |
| blanking |
Portions of the video signal during which both camera and receiver
complete a scan line (horizontal blanking) or field (vertical blanking),
and retrace to begin the next scan. Blanking is the part of the video
signal that contains no picture information. This is the time that the
scanning beam in a TV picture tube is blanked to allow it to track back to
the beginning without drawing diagonal lines across the screen. |
| blanking level |
The level of a video signal separating the range that contains
synchronizing information from the range that contains picture
information. Also known as a pedestal. |
| bleach |
1. Converting a metallic silver image to a halide or other salt which
can be removed from the film with hypo. When bleaching is not carried to
completion, it is called reducing. 2. Any chemical reagent that can be
used for bleaching. |
| Blooming |
This is an effect, sometimes caused when video becomes
whiter-than-white, in which a line that is supposed to be nice and thin
becomes fat and fuzzy on the screen. |
| blue screen |
A special effects procedure in which a subject is photographed in
front of a uniformly illuminated blue or green background. A new
background image can be substituted for the blue or green during the shoot
or in postproduction through the use of chroma key. |
| BNC connector |
Standard twist-connector for attaching coaxial cable to professional
video equipment. |
| bps |
Bits per second. The standard measure of data transmission
speeds. |
| break-down |
The separation of a roll of camera original negative into its
individual scenes. |
| Breezeway |
That portion of the video waveform between the trailing edge of
horizontal sync and the start of color burst. |
| brightness |
(1) The intensity of a color as determined on a scale from black (no
brightness) to white (maximum brightness). The combination of brightness,
hue, and saturation determines the appearance of the colors of a
polychromatic image, whereas the brightness alone determines the
appearance of a monochromatic image's color. (2) The luminance of a video
signal. (3) The brightness of a monitor or video projector measured in
lumens. |
| broadcast monitor |
Television set without receiving circuitry, wired directly to a VTR or
other output device. |
| broadcast quality |
A quality standard for composite video signals set by the NTSC and
conforming to FCC rules. If you plan to record video signal or videotape
for broadcast, it is important to note that devices providing NTSC signals
do not necessarily meet FCC broadcast standards. |
| BS.707 |
This ITU recommendation specifies the stereo audio specifications
(Zweiton and NICAM 728) for the PAL and SECAM video standards. Purchase
the specification. |
| bspline |
A smooth curve that passes on the inner side of the vertices of a
polygon to connect the vertices to interpolate or draw the polygon. 2. A
curve used to define a motion path. |
| BST-OFDM |
See Bandwidth Segmented Orthogonal Frequency Division
Multiplexing. |
| BT.1119 |
Defines the widescreen signaling (WSS) information for NTSC and PAL
video signals. For (B, D, G, H, I) PAL systems, WSS may be present on line
23, and on lines 22 and 285 for (M) NTSC. Purchase the ITU
specification. |
| BT.1124 |
Defines the ghost cancellation reference (GCR) signal for NTSC and
PAL. Purchase the specification. |
| BT.1197 |
Defines the PALplus standard, allowing the transmission of 16:9
programs over normal PAL transmission systems. Purchase the
specification. |
| BT.1302 |
Defines the transmission of 16:9 BT.601 4:2:2 YCbCr digital video
between pro-video equipment. It defines a parallel interface (8-bit or
10-bit, 36 MHz) and a serial interface (360 Mbps). Purchase the
specification. |
| BT.1303 |
Defines the transmission of 16:9 BT.601 4:4:4:4 YCbCrK and RGBK
digital video between pro-video equipment. Two parallel interfaces (8-bit
or 10-bit, 36 MHz) or two serial interfaces (360 Mbps) are used. Purchase
the specification. |
| BT.1304 |
Specifies the checksum for error detection and status for pro-video
digital interfaces. Purchase the specification. |
| BT.1305 |
Specifies the digital audio format for ancillary data for pro-video
digital interfaces. Purchase the specification. Also see SMPTE
272M. |
| BT.1358 |
720 x 480 (59.94 Hz) and 720 x 576 (50 Hz) 4:2:2 YCbCr pro-video
progressive standards. Purchase the specification. Also see SMPTE
293M. |
| BT.1362 |
Pro-video serial interface for the transmission of BT.1358 digital
video between equipment. Two 270 Mbps serial interfaces are used. Purchase
the specification. |
| BT.1364 |
Specifies the ancillary data packet format for pro-video digital
interfaces. Purchase the specification. Also see SMPTE 291M. |
| BT.1365 |
Specifies the 24-bit digital audio format for pro-video HDTV serial
interfaces. Purchase the specification. Also see SMPTE 299M. |
| BT.1366 |
Specifies the transmission of timecode as ancillary data for pro-video
digital interfaces. Purchase the specification. Also see SMPTE
266M. |
| BT.1381 |
Specifies a serial digital interface-based (SDI) transport interface
for compressed television signals in networked television production based
on BT.656 and BT.1302. Purchase the specification. |
| BT.470 |
Specifies the various NTSC, PAL, and SECAM video standards used around
the world. SMPTE 170M also specifies the (M) NTSC video standard used in
the United States. BT.470 has replaced BT.624. Purchase the
specification. |
| BT.601 |
720 x 480 (59.94 Hz), 960 x 480 (59.94 Hz), 720 x 576 (50 Hz), and 960
x 576 (50 Hz) 4:2:2 YCbCr pro-video interlaced standards. Purchase the
specification. |
| BT.653 |
Defines the various teletext standards used around the world. Systems
A, B, C, and D for both 525-line and 625-line TV systems are defined.
Purchase the specification. |
| BT.656 |
Defines a parallel interface (8-bit or 10-bit, 27 MHz) and a serial
interface (270 Mbps) for the transmission of 4:3 BT.601 4:2:2 YCbCr
digital video between pro-video equipment. Purchase the specification.
Also see SMPTE 125M. |
| BT.709 |
This ITU recommendation specifies the 1920 x 1080 RGB and 4:2:2 YCbCr
interlaced and progressive 16:9 digital video standards. Frame refresh
rates of 60, 59.94, 50, 30, 29.97, 25, 24, and 23.976 Hz are supported.
Purchase the specification. |
| BT.799 |
Defines the transmission of 4:3 BT.601 4:4:4:4 YCbCrK and RGBK digital
video between pro-video equipment. Two parallel interfaces (8-bit or
10-bit, 27 MHz) or two serial interfaces (270 Mbps) are used. Purchase the
specification. |
| BTSC |
This EIA TVSB5 standard defines a technique of implementing stereo
audio for NTSC video. One FM subcarrier transmits a L+R signal, and an AM
subcarrier transmits a L-R signal. |
| bug |
An error in a computer program. |
| bump-up |
Copying from one recording medium onto another that is more suitable
for post-production purposes because, for example, it offers better
bandwidth or timecode capabilities. |
| bumping up |
The transfer of a program recorded on a lower quality videotape to a
higher quality videotape (such as from 3/4-inch to 1-inch videotape, or
S-VHS to MII). |
| burn-in |
A visible timecode permanently superimposed (burned in) on footage,
usually in the form of white numbers in a black rectangle. Burned-in
timecode is normally used for tracking timecode during previews or offline
editing. A videotape with burn-in is also called a burn-in dub or window
dub. |
| burn-in-dub |
A duplicate of an original or master tape that includes the time code
reference on-screen and is used as a reference for logging and locating
scenes. |
| burnt-in timecode |
Time code numbers that are superimposed on the picture, generally
created using the overlay feature of a VTR. Used for rought-cut and
edit-list processing. Also called burn in. |
| burst |
The part of the sync signal that controls the hue and color accuracy
of television pictures. |
| Burst Gate |
This is a signal that tells a video decoder where the color burst is
located within the scan line. |
| bus |
1. Electrical signal path between different physical connection
points. 2. System bus on computers, represented by the expansion slot
connectors. 3. Movie-2 bus. |
| BVB |
Black-Video-Black. A preview mode that displays black, newly inserted
video, and then black again. |
| byte |
A sequence of bits. In general, the amount of memory needed for one
character (for example, the letter A) of a specified size, usually 8 or 16
bits. |
| C-mode |
A nonsequential method of assembly in which the edit decision list
(EDL) is arranged by source tape number and ascending source timecode. See
also A-mode, B-mode, D-mode, E-mode, source mode. |
| calibrate |
To fine-tune video levels for maximum clarity during digitizing (from
videotape). |
| camcorder |
A combination camera and recording device that records continuous
pictures and generates a signal for display or recording. |
| Camera Control Unit (CCU) |
The remote control device used to set parameters for one or more
television cameras. |
| camera log |
A record sheet giving details of the scenes photographed on a roll of
original negative. |
| capstan servo |
The regulating device of the capstan as it passes tape through a video
tape recorder. |
| capture |
The process of digitizing video or audio material, usually from a VTR,
and storing it in a file on a hard disk. |
| capture card |
Sometimes called a capture or video board, the logic card installed
into a computer and used to digitize video. Or, for video that is already
digitized, the device that simply transfers the file to the hard disk.
Using a hardware or software codec, the capture card also compresses video
in and decompresses video out for display on a television monitor. |
| Capture Mask effect |
An effect that converts the format of source data during playback. For
example, it could convert video frame data between PAL (25 fps) and NTSC
(29.97 fps) formats. |
| capturing |
Refers to capturing source video for use on a computer. If analog, the
captured video is converted to digital. |
| Cathode Ray Tube (CRT) |
Display device, or picture tube, for video information. |
| CATV |
Community antenna television, now generally meaning cable
TV. |
| CBC |
Canadian Broadcasting Corporation. |
| CBR, (Constant Bit Rate) |
MPEG video compression where the amount of compression does not
change. |
| CCIR |
Comite Consultatif International des Radiocommunications or
International Radio Consultative Committee. The CCIR no longer exists-it
has been absorbed into the parent body, the ITU. For a given "CCIR xxx"
specification, see "BT.xxx". |
| CCIR 601 |
The standard for digitizing component video. Also sometimes called D1
after the VTR format that first used this signal. |
| CCITT |
Abbreviation for Consultative Committee on International Telegraphy
and Telephony; the organization that sets standards and makes
recommendations for international communication. |
| CD |
Abbreviation for compact disc; the digital data storage media proposed
by Philips and Sony. CD is the preferred medium for storing digital
multimedia files because it is inexpensive and has a fairly large capacity
(640 MB). |
| CD-ROM |
Abbreviation for compact disc read-only memory; A CD that cannot be
written to. |
| cell animation |
Also called onion skinning, an animation technique in which a
background painting is held in place while a series of transparent sheets
of celluloid containing objects are placed over the background painting,
producing the illusion of movement. One of the two main types of animation
associated with digital video. Compare frame-based 2-D
animation. |
| cell side |
The base (celluloid) surface of a strip of film. |
| CGI |
Abbreviation for computer graphic imagery. |
| CGMS-A |
Copy Generation Management System - Analog (CGMS-A). See
EIA-608. |
| change list |
A list of instructions produced by Film Composer that is used to track
and compare the differences between two versions of a digital sequence. A
change list is used to update a work print cutting with specified new
edits and revisions. |
| change-over |
In projection, the act of changing from one projector to another,
preferably without interrupting the continuity of projection; or, the
points in the picture at which such a change is made. |
| channel |
1. physical audio input or output. 2. One of several color components
that combine to define a color image. An RGB image is made up of red,
green, and blue color channels. In color correction, you can redefine
color channels by blending color components in different proportions. 3.
See track. |
| channel editor |
The tool used to set keyframes and modify animation curves of the
channels. |
| channel hierarchy |
A set of animation parameters arranged and displayed in a logical
group. A group, or upper-level, channel is called a folder. For example,
the Camera folder contains channels for camera settings such as position,
interest and focal length. |
| Chaoji VideoCD |
Another name for Super VideoCD. |
| character generator (CG) |
A device or software application running on a computer and used for
creating text for display over video (e.g., titles and credits). |
| Charge-Coupled Device, (CCD) |
A light sensitive semi-conductor used as an image sensor in video
camera. |
| chassis |
The housing for removable disk modules. The chassis contains a power
supply, drives, and connectors for each module. |
| checker-board cutting |
A method of assembling alternate scenes of negative in A and B rolls
allowing prints to be made without visible splices. |
| Checksum |
An error-detecting scheme which is the sum of the data values
transmitted. The receiver computes the sum of the received data values and
compares it to the transmitted sum. If they are equal, the transmission
was error-free. |
| Chroma |
The NTSC, PAL, or SECAM video signal contains two parts that make up
what you see on the display: the intensity part, and the color part.
Chroma is the color part. |
| Chroma Bandpass |
In a NTSC or PAL video signal, the luma (black and white) and the
chroma (color) information are combined together. If you want to decode an
NTSC or PAL video signal, the luma and chroma must be separated. A chroma
bandpass filter removes the luma from the video signal, leaving the chroma
relatively intact. This works reasonably well except in images where the
luma and chroma information overlap, meaning that we have luma and chroma
stuff at the same frequency. The filter can't tell the difference between
the two and passes everything. This can make for a funny-looking picture.
Next time you're watching TV and someone is wearing a herringbone jacket
or a shirt with thin, closely spaced stripes, take a good look. You may
see a rainbow color effect moving through that area. What's happening is
that the video decoders thinks that the luma is chroma. Since the luma
isn't chroma, the video decoder can't figure out what color it is and it
shows up as a rainbow pattern. This problem can be overcome by using a
comb filter. |
| Chroma Burst |
See color burst. |
| chroma corrector |
A device that corrects problems related to a video signal's chroma,
color balance, and color noise. |
| Chroma Demodulator |
After the NTSC or PAL video signal makes its way through the Y/C
separator, the colors must be decoded. That's what a chroma demodulator
does. It takes the chroma output of the Y/C separator and recovers two
color difference signals (typically I and Q or U and V). Now, with the
luma information and two color difference signals, the video system can
figure out what colors to display. |
| chroma key |
A video effect wherein a particular area of color (i.e., range of
chrominance) is removed from one video signal and replaced with a
different signal. This effect is often used during newscasts when a
weather map is inserted behind a meteorologist during a newscast. |
| Chroma Trap |
In a NTSC or PAL video signal, the luma (black and white) and the
chroma (color) information are combined together. If you want to decode
the video signal, the luma and chroma must be separated. The chroma trap
is one method for separating the chroma from the luma, leaving the luma
relatively intact. How does it work? The NTSC or PAL signal is fed to a
trap filter. For all practical purposes, a trap filter allows certain
frequencies to pass through, but not others. The trap filter is designed
with a response to remove the chroma so that the output of the filter only
contains the luma. Since this trap stops chroma, it's called a chroma
trap. The sad part about all of this is that not only does the filter
remove chroma, it removes luma as well if it exists within the frequencies
where the trap exists. The filter only knows ranges and, depending on the
image, the luma information may overlap the chroma information. The filter
can't tell the difference between the luma and chroma, so it traps both
when they are in the same range. What's the big deal? Well, you lose luma
and this means that the picture is degraded somewhat. Using a comb filter
for a Y/C separator is better than a chroma trap or chroma
bandpass. |
| chrominance |
The color portion of a video signal that is a mixture of hue and
saturation, but not of luminance (brightness). Every color signal has both
chrominance and luminance. |
| chrominance-to-burst phase |
The difference between the expected phase and the actual phase of the
chrominance portion of the video signal relative to burst phase. |
| chrominance-to-luminance delay |
The difference in time that it takes for the chrominance portion of
the video signal to pass through a system relative to the time it takes
for the luminance portion. Also called relative chroma time. |
| chrominance-to-luminance gain |
The difference between the gain of the of the chrominance portion of
the video signal and the gain of the luminance portion as they pass
through a system. |
| chunking |
The transfer on media files in segments so other workgroup users can
access and use the media before complete files have been sent. |
| CIF |
Common Interface Format or Common Image Format. The Common Interface
Format was developed to support video conferencing. It has an active
resolution of 352 x 288 and a refresh rate of 29.97 frames per second. The
High-Definition Common Image Format (HD-CIF) is used for HDTV production
and distribution, having an active resolution of 1920 x 1080 with a frame
refresh rate of 23.976, 24, 29.97, 30, 50, 59.94, or 60 Hz. |
| cinch marks |
Short scratches on the surface of a motion picture film, running
parallel to its length; these are caused by improper winding of the roll,
permitting one coil of film to slide against another. |
| cinching |
Videotape damage due to creasing or folding. |
| cinemascope |
Trade name of a system of anamorphic widescreen presentation. |
| Cinepak |
A commonly used QuickTime codec for compression of video files on
CD-ROM. Cinipak offers temporal and spatial compression, and data-rate
limiting. |
| cinex strip |
A short test print in which each frame has been printed at a different
exposure level. |
| circle take |
A take from a film shoot that has been marked for use or printing by a
circled number on the camera report. |
| Clamp |
This is basically another name for the DC-restoration circuit. It can
also refer to a switch used within the DC-restoration circuit. When it
means DC restoration, then it's usually used as "clamping". When it's the
switch, then it's just "clamp". |
| clean list (clean EDL) |
An edit decision list (EDL) used for linear editing that has no
redundant or overlapping edits. Changes made during off-line editing often
result in edits that overlap or become redundant. Most computer-based
editing systems can clean an EDL automatically. Contrast with dirty list
(dirty EDL). See also, on-line editing. |
| clip |
1. A segment of source material recorded or digitized into your system
at selected IN and OUT points and referenced in a project bin. The clip
contains pointers to the media files in which the actual digital video and
audio data is stored. 2. In a record in a log, which stands for one shot,
the clip includes information about the start and end timecode for the
shot, the source tape name, and the tracks selected for editing. 3. In
OMFI, a general class of objects in the OMF Interchange class hierarchy
representing shared properties of source clips, filler clips, attribute
clips, track references, timecode clips, and edge code clips. A clip is a
subclass of a component. See also master clip, media files,
subclip. |
| clip properties |
A clip's specific settings, including frame size, compressor, audio
rate, etc. |
| clipping |
The cropping of peaks (overmodulation) of the white or the black
portions of a video signal. |
| Clipping Logic |
A circuit used to prevent illegal conversion. Some colors can exist in
one color space but not in another. Right after the conversion from one
color space to another, a color space converter might check for illegal
colors. If any appear, the clipping logic is used to limit, or clip, part
of the information until a legal color can be represented. Since this
circuit clips off some information and is built using logic, it's not too
hard to see how the name "clipping logic" was developed. |
| clock timecode |
See drop-frame timecode. |
| Closed Captioning |
A service which decodes text information transmitted with the video
signal and displays it on the display. For NTSC, the caption signal may be
present on lines 21 and 284. For PAL, the caption signal may be present on
lines 22 and 334. See the EIA-608 specification for (M) NTSC usage of
closed captioning and the EIA-708 specification for DTV support. For
MPEG-2 video, including ATSC and DVB, the closed caption data are
multiplexed as a separate data stream within the MPEG-2 bitstream. It may
use the picture layer user_data bits as specified by EIA-708, or in PES
packets (private_stream_1) as specified by ETSI EN 301 775. For DVD,
caption data may be 8-bit user_data in the group_of_pictures header
(525/60 systems), a digitized caption signal (quantized to 16 levels) that
is processed as normal video data (625/50 systems), or a subpicture that
is simply decoded and mixed with the decoded video. |
| Closed Subtitles |
See subtitles. |
| Closeup, (CU) |
See also ECU. |
| CMYK |
This is a color space primarily used in color printing. CMYK is an
acronym for Cyan, Magenta, Yellow, and blacK. The CMYK color space is
subtractive, meaning that cyan, magenta, yellow and black pigments or inks
are applied to a white surface to remove color information from the white
surface to create the final color. The reason black is used is because
even if a printer could print hues of cyan, magenta, and yellow inks
perfectly enough to make black (which it can't for large areas), it would
be too expensive since colored inks cost more than black inks. So, when
black is used, instead of putting down a lot of CMY, they just use
black. |
| coaxial cable |
A single conductor, braid-shielded cable used to carry video signals.
Has a 75 ohm impedance. |
| codec |
Contraction of compression/decompression algorithm; used to encode and
decode, or compress and decompress data, such as sound and video files.
Common codecs include those that convert analog video signals to
compressed digital video files (e.g., MPEG), or that convert analog sound
signals into digital sound files (e.g., RealAudio). |
| Coded Orthogonal Frequency Division Multiplexing |
Coded orthogonal frequency division multiplexing, or COFDM, transmits
digital data differently than 8-VSB or other single-carrier
approaches. Frequency division multiplexing means that the data to be
transmitted is distributed over many carriers (1,705 or 6,817 for DVB-T,
as opposed to modulating a single carrier. Thus, the data rate on each
COFDM carrier is much lower than that required of a single carrier. The
COFDM carriers are orthogonal, or mutually perpendicular, and forward
error correction ("coded") is used. COFDM is a multiplexing technique
rather than a modulation technique. One of any of the common modulation
methods, such as QPSK, 16-QAM or 64-QAM, is used to modulate the COFDM
carriers. |
| coefficient recording |
A form of data bit-rate reduction used by Sony in its Digital Betacam
format and with its D-2 component recording accessory, the DFX-C2.
Co-efficient recording uses a discrete cosine transformation and a
proprietary information handling scheme to lower the data rate generated
by a full bit-rate component digital signal. Such a data bit-rate
reduction system allows component digital picture information to be
recorded more efficiently on VTRs. |
| COFDM |
See coded orthogonal frequency division multiplexing. |
| color balance |
Adjustment of the colour circuitry of a TV camera to the colour
temperature of the light source for a given scene. |
| color bars |
An electronically-generated test signal usually consisting of six
vertical strips of colour. A standard test signal that appears as a series
of vertical rows of colour by which the chrominance and video levels of a
camera's output or a recorded signal can be checked. |
| color burst |
The portion of the composite video signal that contains a sample of
the color subcarrier. The color burst is used to establish a reference for
the color information that follows it, and for decoding the color
information of the signal. Burst is many cycles of 3.58 MHz pulses
recorded during the horizontal blanking interval and used to establish
phase relationships for determining the hue. A color television receiver's
color oscillator is phase locked to the color burst. |
| color correction |
The process of adjusting the color characteristics of video material
to achieve an accurate representation of color and consistency of color
from one clip in a sequence to another. The term generally refers to
adjustments made across all the video in a program rather than to
individual color changes made as part of a single effect. |
| Color Decoder |
See chroma demodulator. |
| Color Demodulator |
See chroma demodulator. |
| Color Difference |
All of the color spaces used in color video require three components.
These might be R'G'B', Y'IQ, Y'UV or Y'(R' - Y')(B' - Y'). In the Y'(R' -
Y')(B' - Y') color space, the R' - Y' and B' - Y' components are often
referred to as color difference signals for obvious reasons. They are made
by subtracting the luma (Y') from the red and blue components. I and Q and
U and V are also color difference signals since they are scaled versions
of R' - Y' and B' - Y'. All the Ys in each of the Y'IQ, Y'UV and Y'(R' -
Y')(B' - Y') are basically the same, although they are slightly different
between SDTV and HDTV. |
| Color Edging |
Extraneous colors that appear along the edges of objects, but don't
have a color relationship to those areas. |
| Color Encoder |
The color encoder does the exact opposite of the color decoder. It
takes two color difference signals, such as I and Q or U and V, and
combines them into a chroma signal. |
| color frame |
"A sequence of video fields required to produce a complete pattern of
both field and frame synchronization and color subcarrier synchronization.
The NTSC system requires four fields; PAL requires eight. " |
| Color Key |
This is essentially the same thing as chroma key. |
| Color Killer |
A color killer is a circuit that shuts off the color decoding if the
incoming video does not contain color information. How does this work? The
color killer looks for the color burst and if it can't find it, it shuts
off the color decoding. For example, let's say that a color TV is going to
receive material recorded in black and white. Since the black and white
signal does not contain a color burst, the color decoding is shut off. Why
is a color killer used? Well, in the old days, the color decoder would
still generate a tiny little bit of color if a black and white
transmission was received, due to small errors in the color decoder,
causing a black and white program to have faint color spots throughout the
picture. |
| Color Modulator |
See color encoder. |
| color picker |
A tool used to plot colours in an image. |
| Color Purity |
This term is used to describe how close a color is to the theoretical.
For example, in the Y'UV color space, color purity is specified as a
percentage of saturation and +/-q, where q is an angle in degrees, and
both quantities are referenced to the color of interest. The smaller the
numbers, the closer the actual color is to the color that it's really
supposed to be. For a studio-grade device, the saturation is +/-2% and the
hue is +/-2 degrees. On a vectorscope, if you're in that range, you're
studio quality. |
| color reference burst |
The color synchronizing signal included as part of the overall
composite video signal. When compared with the color subcarrier signal,
the color reference burst determines the hue of the video
image. |
| Color Reversal Intermediate, (CRI) |
A duplicate colour negative prepared by reversal processing. |
| Color Space |
A color space is a mathematical representation for a color. No matter
what color space is used -- RGB, Y'IQ, Y'UV, etc. -- orange is still
orange. What changes is how you represent orange. For example, the RGB
color space is based on a Cartesian coordinate system and the HSI color
space is based on a polar coordinate system. |
| color subcarrier |
The 3.58 MHz (NTSC) or 4.43 MHz (PAL) signal that carries color
information. The color subcarrier is superimposed onto the luminance
level. Its amplitude represents saturation and its phase angle represents
hue. |
| Color Temperature |
Color temperature is measured in degrees Kelvin. If a TV has a color
temperature of 8,000 degrees Kelvin, that means the whites have the same
shade as a piece of pure carbon heated to that temperature. Low color
temperatures have a shift towards red; high color temperatures have a
shift towards blue. The standard for video is 6,500 degrees Kelvin. Thus,
professional TV monitors use a 6,500-degree color temperature. However,
most consumer TVs have a color temperature of 8,000 degrees Kelvin or
higher, resulting in a bluish cast. By adjusting the color temperature of
the TV, more accurate colors are produced, at the expense of picture
brightness. |
| color timing |
The process wherein colors are referenced and alternate odd and even
color fields are matched to ensure colors match from shot to shot. Most
commonly found in high-end equipment, such as Betacam SP. |
| color wheel |
A circular graph that maps hue values around the circumference and
saturation values along the radius. Used in the Color Correction tool as a
control for making hue offset and secondary color correction
adjustments. |
| ColorStream, ColorStream Pro, ColorStream HD |
The name Toshiba uses for the analog YPbPr video interface on their
consumer equipment. If the interface supports progressive SDTV
resolutions, it is called ColorStream Pro. If the interface supports HDTV
resolutions, it is called ColorStream HD. |
| Common Image Format |
See CIF. |
| Common Interface Format |
See CIF. |
| compile |
To compute an image or effect using a nonlinear editing, compositing,
or animation program. The result is generally saved in a file on the
computer. Also called render. component video |
| component video |
The structuring of the video signal whereby color and luminance
signals are kept separate from one another using the color-subtraction
method Y (luminance), B–Y (blue minus luminance) and R–Y (red minus
luminance), with green derived from a combination. Two other component
formats are RGB and YUV. |
| composite |
An analog video signal comprising both luminance and
chrominance. |
| composite blanking |
See blanking. |
| composite print |
A motion picture print with both picture and sound on the same strip
of film. |
| composite sound track |
A sound track containing all required sound elements — usually dialog,
music, and effects mixed in correct proportions. |
| composite sync |
A signal that comprises only horizontal sync pulses, vertical sync
pulses, and equalizing pulses, and has a no-signal reference level. |
| composite video |
A signal in which the luminance, chrominance, and sync information are
combined into one signal using one of the coding standards (e.g., NTSC,
PAL, or SECAM). The signal must take the form of composite video before it
can be broadcast or recorded by standard means. Until recently, most
monitors and projectors accepted only composite video signals, though many
presently accept RGB signals. Contrast with component video. |
| compositing |
Layering multiple pictures on top of each other. A cutout or matte
holds back the background and allows the foreground picture to appear to
be in the original picture. |
| composition |
The standard term used by OMF Interchange to refer to an edited
sequence made up of a number of clips. The OMF equivalent of a sequence in
an Avid system. |
| compression |
The translation of audio or video data into a format that requires
less storage space than the original data. See also, codec. |
| compression ratio |
The ratio of the amount of data in the original video compared to the
amount of data in the compressed video. The higher the ratio the greater
the compression. |
| Conditional Access |
This is a technology by which service providers enable subscribers to
decode and view content. It consists of key decryption (using a key
obtained from changing coded keys periodically sent with the content) and
descrambling. The decryption may be proprietary (such as Canal+,
DigiCipher, Irdeto Access, Nagravision, NDS, Viaccess, etc.) or
standardized, such as the DVB common scrambling algorithm and OpenCable.
Conditional access may be thought of as a simple form of digital rights
management. Two common DVB conditional access (CA) techniques are
SimulCrypt and MultiCrypt. With SimulCrypt, a single transport stream can
contain several CA systems. This enables receivers with different CA
systems to receive and correctly decode the same video and audio streams.
With MultiCrypt, a receiver permits the user to manually switch between CA
systems. Thus, when the viewer is presented with a CA system which is not
installed in his receiver, they simply switch CA cards. |
| confidence value |
A measurement, expressed as a percentage, of the probability that the
pattern the system finds during a motion tracking operation is identical
to the pattern for which the system is searching. During a motion tracking
operation, Avid Symphony calculates a confidence value for each tracking
data point it creates. |
| configuration file |
Contains a list of the device parameters, resource directory path
names, and image file extensions that are required to run fire*. |
| conform |
To prepare a complete version of your project for viewing. The version
produced might be an intermediate working version or the final
cut. |
| conforming |
The process wherein an off-line edited master is used as a guide for
performing final edits. |
| conforming a film negative |
The mathematical process that the editing system uses to ensure that
the edits made on a videotape version of a film project (30 fps) are frame
accurate when they are made to the final film version (24
fps). |
| Console |
A display that lists the current system information and chronicles
recently performed functions. It also contains information about
particular items you are editing, such as the shots in your sequence or
clips selected from bins. |
| consolidate |
To make copies of media files or portions of media files, and then
save them on a drive. The Consolidate feature operates differently for
master clips, subclips, and sequences. |
| constant |
An option for the interpolation and/or extrapolation of an animation
curve that produces a square or stepped curve. |
| Constant Bit Rate, (CBR) |
Constant bit rate (CBR) means that a bitstream (compressed or
uncompressed) has the same number of bits each second. |
| Contouring |
This is an image artifact caused by not having enough bits to
represent the image. The reason the effect is called "contouring" is
because the image develops vertical bands of brightness. |
| contrast |
The range of difference between the lightest and darkest values of a
picture, or maximum and minimum brightness values. |
| control point |
A location on a Bézier curve that controls its direction. Each control
point has two direction handles that can extend from it. |
| control track |
A continuous, stable, low-frequency signal recorded onto tape. It is
used to identify frame locations and control the playback of the video
signal. Electronic sprocket holes recorded on video tape to guide the
heads and control tape transport during playback. A signal recorded on
video tape to allow the tape to play back at a precise speed in any VTR.
Analogous to the sprocket holes on film. |
| control track editing |
The linear editing of videotape with equipment that reads the control
track information to synchronize the editing between two decks. Contrast
with timecode editing. |
| control-L |
See LANC. |
| convergence |
(1) The accuracy of the positions of the red, green, and blue beams of
a color monitor or projector. (2) The adjustment of the red, green, and
blue electron beams in a monitor or video projector to align the red,
green and blue images. |
| CPU |
Central processing unit. The main computational section of a computer
that interprets and executes instructions. |
| crash edit |
An edit that is electronically unstable, such as one made using the
pause control on a deck, or using a noncapstan served deck. |
| crash recording |
See hard recording. |
| crawl |
Sideways movement of text across a screen. |
| crawling text |
Text that moves horizontally over time. Examples include stock and
sports score tickers that appear along the bottom of a television
screen. |
| Creepy Crawlies |
Yes, this is a real video term! Creepy-crawlies refers to a specific
image artifact that is a result of the NTSC system. When the nightly news
is on, and a little box containing a picture appears over the
anchorperson's shoulder, or when some computer-generated text shows up on
top of the video clip being shown, get up close to the TV and check it
out. Along the edges of the box, or along the edges of the text, you'll
notice some jaggies "rolling" up (or down) the picture. That's the
creepy-crawlies. Some people refer to this as zipper because it looks like
one. |
| crop box |
A box that you superimpose over frames, either automatically or
manually, to limit colour corrections, key setups etc., to the area inside
the box. |
| cropping |
The redefining of image boundaries, usually by electronically removing
the top, bottom, left, or right sides of the image. |
| Cross Color |
This occurs when the video decoder incorrectly interprets
high-frequency luma information (brightness) to be chroma information
(color), resulting in color being displayed where it
shouldn't. |
| Cross Luma |
This occurs when the video decoder incorrectly interprets chroma
information (color) to be high-frequency luma information
(brightness). |
| cross mod |
A test method for determining the optimum print requirements for a
variable area sound track. |
| Cross Modulation |
A condition when one signal erroneously modulates another
signal. |
| crossfade |
An audio transition in which the outgoing sound gradually becomes less
audible as the incoming sound becomes more distinct. Also called an audio
dissolve. See also dissolve, fade. |
| Crosstalk |
Interference from one signal that is detected on another. |
| crushing the blacks |
The reduction of detail in the black regions of a film or video image
by compressing the lower end of the contrast range. |
| cue |
To shuttle a videotape to a predetermined location. |
| cue channel |
A dedicated track for sync pulses or timecode. |
| cue mark |
Marks used to indicate frames of interest on a clip. |
| curl |
A defect of a photographic film consisting of unflatness in a plane
cutting across the width of the film. Curl may result from improper drying
conditions, and the direction and amount of curl may vary with the
humidity of the air to which the film is exposed. |
| Curves graph |
An X, Y graph that plots input color values on the horizontal axis and
output color values on the vertical axis. Used in the Color Correction
tool as a control for changing the relationship between input and output
color values. |
| cut |
1. An instantaneous transition from one video source to another. 2. A
section of source or record tape. |
| cut list |
A series of output lists containing specifications used to conform the
film work print or negative. See also dupe list. |
| cutout |
See matte. |
| cutting |
The selection and assembly of the various scenes or sequences of a
reel of film. |
| CVBS |
Abbreviation for Composite Video Baseband Signal or Composite Video,
Blanking, Synchronization. |
| cycles |
An option for the extrapolation curve that produces cycles in the
curve based on the values of the first and last keyframes in the
curve. |
| D-mode |
An A-mode edit decision list (EDL) in which all effects (dissolves,
wipes, graphic overlays) are performed at the end. See also A-mode,
B-mode, C-mode, E-mode, source mode. |
| D-to-A converter |
An electronic device that converts digital signals into analog
signals. |
| D1 |
Digital video tape format using the CCIR 601 standard to record 4:2:2
component video on 19mm tape. A high quality of video tape format
generally available. The first digital video tape format, hence D1. |
| D16 |
A format to store film resolution images on D1 format tape recorders.
Records one film frame in the space normally used for 16 video
frames. |
| D2 |
Digital video tape format using the 4fsc method to record composite
digital video. Uses 19mm tape and a cassette similar to D1. The second
digital video tape format, hence D2. |
| D3 |
Digital video tape format using 4fsc composite signals like D2, but
recorded on ˝" tape. The third digital video tape format... |
| D4 |
Doesn't exist, so don't worry about it. |
| D5 |
Digital video tape format using CCIR 601, 4:2:2 video. Uses the same
cassette as D3. Betcha can guess why its called D5. |
| D9 |
Digital Video tape format from JVC, before called JVC Digital-S |
| DAE |
Digidesign Audio Engine. A trademark of Avid Technology, Inc. The
application that manages the AudioSuite plug-ins. |
| dailies |
The first positive prints made by the laboratory from the negative
photographed on the previous day. |
| dailies |
Film prints or video transfers of recently shot film material,
prepared quickly so that production personnel can view and evaluate the
previous day's shooting before proceeding. Also called rushes, primarily
in the United Kingdom. |
| DAT |
Abbreviation for digital audio tape; a digital
audio-recording-and-playback system developed by Sony. DAT uses a small,
4mm tape and has a signal quality that can surpass that of the CD. In
audio, DAT is often used for mastering a final mix of a sound track or
musical composition. In computers, it is often used for archiving or
backing up data and may be referred to as DDS (Digital Data
Storage). |
| data rate |
The amount of data moved over a period of time, such as 10MB per
second. Often used to describe a hard drive's ability to retrieve and
deliver information. |
| DAVIC |
Abbreviation for Digital Audio Visual Council. It's goal was to create
an industry standard for the end-to-end interoperability of broadcast and
interactive digital audio-visual information, and of multimedia
communication. The specification is now ISO/IEC 16500 (normative part) and
ITR 16501 (informative part). |
| dB |
Abbreviation for decibels, a standard unit for expressing relative
power, voltage, or current. |
| dBm |
Measure of power in communications. 0 dBm = 1 mW, with a logarithmic
relationship as the values increase or decrease. In a 50-ohm system, 0 dBm
= 0.223 volts. |
| dBw |
Decibels referenced to 1 watt. |
| DC 30 editing mode |
An edit mode in Premiere—specifically for DC30 users—that allows video
to be streamed out of the DC30 capture card installed in a computer
running Windows. |
| DC Restoration |
DC restoration is what you have to do to a video signal after it has
been AC-coupled and has to be digitized. Since the video waveform has been
AC-coupled, we no longer know absolutely where it is. For example, is the
bottom of the sync tip at -5v or at 1v? In fact, not only don't we know
where it is, it also changes over time, since the average voltage level of
the active video changes over time. Since the ADC requires a known input
level and range to work properly, the video signal needs to be referenced
to a known DC level. DC restoration essentially adds a known DC level to
an AC-coupled signal. In decoding video, the DC level used for DC
restoration is usually such that when the sync tip is digitized, it will
be generate the number 0. |
| DCT |
This is short for Discrete Cosine Transform, used in the MPEG, H.261,
and H.263 video compression algorithms. |
| De-emphasis |
Also referred to as post-emphasis and post-equalization. Deemphasis
performs a frequency-response characteristic that is complementary to that
introduced by pre-emphasis. |
| De-emphasis Network |
A circuit used to restore a frequency response to its original
form. |
| Decibel, (DB) |
A unit of measure applied to both sound and electrical signals, based
on a logarithmic scale. A logarithmic unit that expresses the ratio
between a signal and a reference signal. For voltages, dB=20 log (V
measured/V nominal). Also referred to as "db's." A logarithmic unit that
expresses the ratio between a signal and a reference signal. One-tenth of
a Bel, used to define the ratio of two powers, voltages, or currents, in
terms of gains or losses. It is 10x the log of the power ratio and 20x the
voltage or current ratio. |
| Decimation |
When a video signal is digitized so that 100 samples are produced, but
only every other one is stored or used, the signal is decimated by a
factor of 2:1. The image is now 1/4 of its original size, since 3/4 of the
data is missing. If only one out of five samples were used, then the image
would be decimated by a factor of 5:1, and the image would be 1/25 its
original size. Decimation, then, is a quick-and-easy method for image
scaling. Decimation can be performed in several ways. One way is the
method just described, where data is literally thrown away. Even though
this technique is easy to implement and cheap, it introduces aliasing
artifacts. Another method is to use a decimation filter, which reduces the
aliasing artifacts, but is more costly to implement. |
| deck controller |
A tool that allows the user to control a deck using standard functions
such as shuttle, play, fast forward, rewind, stop, and eject. |
| decode |
To divide a composite video signal into its separate components. |
| decoder |
A device that decrypts component signals from a composite (encoded)
source. Decoders are used in video displays and processing hardware where
component signals are needed from a composite source. |
| decompose |
To create new, shorter master clips based on only the material you
have edited and included in your sequence. |
| definition |
The aggregate of fine details of a video image on-screen. The higher
the definition, the more discernable the details. |
| degauss |
To demagnetize (erase) all recorded material on a magnetic videotape,
an audiotape, or the screen of a color monitor. |
| deinterlace |
Separation of field 1 and fie |