Digital Intermediate Glossary

2k

an image that is roughly 2000 pixels along one edge

4k

an image that is roughly 4000 pixels along one edge

academy aperture

a specific aperture used for film material

action safe

the safe area defining where the picture content can be seen

alias

the effect where the edges of pixels are clearly visible; the process of creating this effect

alpha

transparency information; an image channel not normally displayed

analogue

a continuously variable signal; not digital

anamorphic

a lens used to compress an image; an image that has been compressed in this way, typically along the horizontal axis; a format using anamorphic compression

anamorphic squeeze

the process of distorting an image to an anamorphic format

answer print

a film print that is used to generate release prints

anti-alias

a technique used to minimise aliasing effects

aperture

a part of an imaging device used to control the amount of light received; the area of a frame used for an image

aperture correction

see “sharpen”

artefact

a fault affecting an image

ASA

see “film speed”

aspect ratio

the ratio of an image’s width to its height

authoring

the process of combining elements together, typically for the creation of DVDs

background plate

a shot serving as background for some other element, typically for a visual effect; a placeholder for a shot

banding

see “posterise”

bandwidth

the rate of data transfer, usually measured in bytes per second

bit

“binary digit”; the smallest unit of computer data

bit-depth

see “precision”

bitmap

a raster image; an image containing only black or white pixels; a Windows bitmap formatted image

bit-rate

a measurement of bandwidth

bluescreen

see “chromakey”

broadcast-safe colour

see “legal colour”

burn-in

to encode some information directly into an image

byte

8 bits

cache

a store of solutions to recent or frequently-used calculations for fast access; a copy of an image held for fast display or processing

cadence

the ordering of frames in a pulldown sequence

cathode-ray tube

a device that uses an electron beam fired down a vacuum tube to create an image

CCD

see “charge-coupled device”

CDL

see “colour decision list”

centre cut-out

a method for converting an image to another aspect ratio by cropping the picture around the centre

CG

“computer-generated”; generated by a computer; images that have been generated by a computer

channel

an individual component in a digital image

charge-coupled device

a device used to detect and measure incident light, typically arranged in an array to allow recording of images

chroma

see “chromacity”

chromacity

the colour component of light

chromakey

a method for creating a key based on a certain colour; a screen of solid colour; the process of shooting foreground elements in front of such a screen

cinemascope

a specific anamorphic aperture used for film material

cineon printing density

a digital image colour space designed to mimic the response of film

clone

make an exact copy of a video tape using digital means

closed captions

text elements that do not form part of the recorded image

CLUT

see “look-up table”

CMYK

a colour model combining proportions of cyan, magenta, yellow and black together

colour cube

see “look-up table”

colour space

the reproducible colour range of a system

colour timing

see “colour grading”

colour-correction

see “colour grading”

colour-grading

the process of altering the colours of an image

colour decision list

A list of colour grading parameters applied to footage

component video

video signal that encodes each colour component separately

composite

to combine two or more image elements together

composite video

video signal that encodes colour components together

compression

the process of making something smaller, either by discarding or re-organising information; also applies to colour ranges and image dimensions

conform

the process of assembling source material together into a programme, usually automatically

consolidate

to combine elements together to one location; to remove all extraneous material from a programme

contrast ratio

the ratio of the brightest to the darkest colour in an image

corruption

a fault in a digital file

CPD

see “cineon printing density”

crop

to remove one or more edges of an image

CRT

see “cathode-ray tube”

cue

to go to a specific point in a video sequence or on a tape

cut

a version of an edited programme; a transition involving going directly from a frame of one shot to a frame of another shot; to remove; to end a shot

cut list

a list of edits making up a sequence or programme, usually specified in terms of key numbers

dailies

raw, unedted footage from a shoot; the process of watching such footage

data

information, typically in digital form

day-for-night

a technique for shooting a scene during the day, and using various processes to make it appear to have been shot at night

DCDM

see “digital cinema distribution master”

D-cinema

see “digital cinema”

DCP

see “digital cinema package”

decrypt

to rearrange encrypted data so that it can be viewed correctly

deinterlace

the process of removing interlacing from a frame or sequence

density

the level of developed grains at a specific point in film material

detective quantum efficiency

an objective measurement of image quality, combining MTF measurements with signal-to-noise ratio measurements

DF

see “drop-frame timecode”

difference matte

an image showing the difference in pixel values between two images

digital

a signal consisting of discrete units of information

digital cinema

cinemas that use digital material rather than film material; the process of providing digital cinema

digital cinema distribution master

the digital master used for digital cinema

digital cinema package

a collection of elements for digital cinema projection

digital dailies

the process of watching dailies in a digital environment

digital source master

the digital master created at the end of the digital intermediate process

digital versatile disc

optical disc-based digital storage medium; consumer-grade digital video format

digital video

video material encoded in a digital format; moving images encoded in a digital format; consumer-grade digital video format

digitise

to make digital, usually by sampling an analogue signal

dissolve

a transition involving a blend from one shot to another

D-max

the maximum density level in a film image

D-min

the minimum density level in a film image

down-rez

see “down-sample”

down-sample

to decrease the number of pixels in an image, usually by interpolation

DQE

see “detective quantum efficiency”

drop-frame timecode

a timecode method whereby certain frame numbers are omitted to allow playback to be sychronised to real-time clocks

drop-out

a fault on a video signal where picture information is missing or damaged

dropped frames

when individual frames are omitted from a sequence; when this happens during playback

DSM

see “digital source master”

dub

to copy, usually applies to videotapes

dust-bust

the process of removing dust, scratches and the like from scanned film

DV

see “digital video”

DVD

see “digital versatile disc”

dynamic

a parameter that varies over time; an effect utilising varying parameters

dynamic range

the response of a system to various luminance levels; the system’s capacity for encoding different luminance levels

edit

to make changes to something; to manually assemble footage together to form a sequence or programme

edit decision list

a list of edits making up a sequence or programme, usually specified in terms of reels and timecodes

EDL

see “edit decision list”

EI

see “exposure index”

encode

the process of storing data in a particular format

encrypt

to alter data so that it cannot be accessed without the proper credentials

enlarger

a device used to increase the size of a photographic image

event

a shot in a sequence; a shot in an EDL

exposure

a measurement of the amount of light incident on a particular point over time; the act of exposing a sensitive material to light

exposure index

a method for recording film speed, also accounting for other factors

exposure latitude

the potential range of exposure recordable by a given material

extract

to remove a shot from a sequence, so that the adjacent shots cut together

eye-match

to match two images visually

false colour

a method for applying colour to a monochrome image

field

half of a video frame, usually recorded at a different time from each other, usually in an interlaced manner

file header

the area of a file containing metadata

film negative

film material where the images have reversed colour, requiring printing before being able to be viewed correctly

film positive

film material where the images can be viewed directly, such as by projection

film print

see “film positive”

film scanner

a device used to digitise film images

film speed

the sensitivity of film material to light; a value for this

film stock

a type of film material with specific characterstics

film-out

the process of recording material onto film from a digital source

filter

a device attached to an imaging system to modify the image recorded; a digital process used to modify images

firewire

IEEE1394 specification; a data transfer technology

flare

an effect caused by light reflection on the lens; a process mimicking this effect

fog

contamination by light, usually stray light; an effect to add depth to an image

footage

a collection of images

FPS

frames per second; see also “frame rate”

frame

a single image in a sequence; to position and compose an image; the area containing a viewable image

frame patch

the method of replacing individual frames in a shot with other frames; a frame used for this purpose

frame rate

the speed at which individual image frames are displayed to form a moving sequence, usually measured in Hertz or frames per second

full aperture

a method of recording images whereby the maximum imaging area is used, usually for film material

fullscreen

a 4:3 image format

gamma

the relationship between a pixel and the corresponding point of light displayed on a device such as a television; a value describing the amount of gamma correction used; a method for altering the brightness and contrast of an image

gamma-correction

the process of modifying a pixel value for display on a device with a non-linear response

gamut

see colour space

gate

a part of an imaging device used to crop an image, usually to constrain the image to a particular format

gauge

the size of a film image

GB

see “gigabyte”

generation

a copy of something, usually of analogue material

generation loss

the loss of quality suffered through creating a new generation

gigabyte

1024 megabytes

global grading

see “primary grading”

grading flash

a discontinuity in colour in a sequence

grading list

see “grading metadata”

grading metadata

data concerning grading to be applied to an image or sequence

grain

a light-sensitive region in film material; a the smallest part of a film image

graininess

a subjective measurement of the amount of grain in an image

granularity

an objective measurement of the amount of grain in an image

greenscreen

see “chromakey”

greyscale

an image without any chromacity

handle

additional frames of a shot that extend beyond the cut-points

Hard cut

a cut within source footage

HD

see “high definition”

HDR

see “high dynamic range image”

HDTV

see “high definition television”

HDV

consumer-grade high definition video format

headroom

the region of an imaging system above the maximum displayable brightness value, or below the minimmum displayable brightness value

high definition

video format with increased resolution

High definition television

a video signal that carries high definition video suitable for television; a television that can display this signal

high dynamic range image

a digital image format capable of encoding colour in a more objective way, typically as coordinates on the CIE chromacity chart

histogram

a method for displaying the distribution of pixel values in a digital image

HLS

a colour model combining hue angle, luminance and saturation together

hue

the angle of the wavelength of a colour, as measured on a colour wheel

in-place edit

the process of making changes to a file directly without creating new files or rendering

interlace

a method of combining two fields in a frame, by encoding lines of the image alternately to each frame

inter-neg

see “inter-negative”

inter-negative

an intermediate film negative

interpolate

to estimate intermediate values, usually in terms of pixel values

inter-pos

see “inter-positive”

inter-positive

an intermediate film positive

inverse telecine

the process of relating an edited pulldown sequence to the original film footage

ISO

see “film speed”

jog

to progress through footage, usually a frame at a time

KB

see “kilobyte”

key

a region of transparency or selection, usually based on a colour range; the method used to create transparency or selection; the colour used to do this

key number

a code used to uniquely identify a frame of film

keycode

see “key number”

keyframe

a frame used to specify a particular setting at a particular point in time, usually for dynamic effects or animation purposes; the process of creating keyframes

kilobyte

1024 bytes

Lab

a colour model combining luminance and chromacity coordinates together

lag

an effect whereby frames are not delivered fast enough for real-time display

latent image

the invisible image formed on photographic film after exposure that is developed to form a visible image

leader

frames that preceed a programme or sequence

legal colour

a colour that is within a particular colour space, typically in video formats

letterbox

a method for converting an image to another aspect ratio by filling the missing area with black

lift

to remove a shot from a sequence without altering the timing of the sequence, usually leaving a gap; to adjust the black level in an image

line spread function

see “spread function”

log

see “logarithmic”

logarithmic

measurement on a logarithmic scale; an image encoded on a logarithmic scale

longitudinal timecode

timecode information that is encoded to a specific part of a video tape

look-up table

a method for replacing stored colours with other colours, typically used to convert between different colour spaces

lossless compression

compression that does not result in any loss of information

lossy compression

compression that results in a loss of information

LTC

see “longitudinal timecode”

luma

gamma-corrected luminance

luminance

the energy of a particular colour; the component of an image pixel or signal measuring this; synonomous with brightness or luminosity

LUT

see “look-up table”

mask

a shape used to constrain an effect applied to an image

master

to create a final production for a specific format; the media containing this material

matrix

see “video-switching matrix”

matte

an image used to constrain an effect applied to another image

MB

see “megabyte”

megabyte

1024 kilobytes

megapixel

a unit of measurement of digital image area; one megapixel is 1,000,000 pixels

metadata

data concerning other data; typically data that can be encoded that does not contain image information

modulation transfer function

an objective measurement of a system’s response to different frequencies

monochrome

an image consisting of a single colour

motion-control

a programmable motorised unit, allowing for precise and repeatable motion

movie

a film production; a moving picture sequence; a digital moving picture sequence file

MTF

see “modulation transfer function”

NDF

see “non-drop-frame timecode”

nearline storage

storage whose contents are accessible, but at a slower rate than online storage

NLE

see “non-linear editing”

noise

random fluctuations in a signal

non-drop-frame timecode

a timecode method whereby frame numbers are counted in a continuous fashion

non-linear editing

the ability to edit footage in any order

NTSC

“National Television Systems Committee”; a video standard used in most of America and parts of East Asia

offline edit

editing phase performed without making permanent changes, usually without working with original, full-quality material

offline storage

storage whose contents are not immediately accessible

one-light grading

to apply simple, verall colour grading to an image, usually for viewing purposes

online edit

editing phases where changes during the offline edit are replicated with the original, full-quality source material

online storage

storage whose contents are immediately available

optical

pertaining to a lens or image-recording system; an effect applied to an image; an image or shot that has had an effect applied to it

overscan

the region of image outside of the safe area

PAL

“Phase-Alternate Lines”; a video standard used throughout most of the world

pan & scan

the process of repositioning and resizing material to fit different aspect ratios; footage that has undergone this process

panorama

an image that captures a wide field of view; an image formed by combining multiple images next to each other

parallax

the effect of distant objects seeming to move at a slower rate than closer ones

perf

see “perforation”

perforation

a hole cut into the edge of a strip of film, used for positioning images correctly

picture line-up generation equipment

a device used to calibrate a display

pin-registration

a feature of some film scanners that allows for more precise registration of film scans

pixel

“picture element”; the smallest spatial component of a digital image

pixel aspect ratio

the ratio of a pixel’s width to its height

PLUGE

see “picture line-up generation equipment”

point spread function

see “spread function”

posterise

an artefact in digital images where the colour precision is too low, creating visible steps in colour; a process used to exaggerate this effect

post-roll

a period used by a linear system to decelrate from realtime playback speed to a stop; the amount of time required to do so

precision

the degree of accuracy of reproducing colours; the degree of accuracy of recording colours; a measurement for this, usually in bits-per-pixel or bits-per-channel

pre-roll

a period used by a linear system to accelerate from a stop to realtime playback speed; the amount of time required to do so

primary grading

colour grading that affects the entire image

printer light

a measurement of grading film chemically; a light used for making film prints

printer point

see “printer light”

programme

a collection of shots making up a complete production

progressive scan

a frame that does not consist of fields; a method of recording video without recording fields

progressive segmented frames

a method of storing progressive scan video material using fields

proxy image

a (usually downsampled) copy of an image, to which changes can be made that are later applied to the original image

PsF

see “progressive segmented frames”

pulldown

a method to translate film frames to video frames; a sequence that has undergone this process

punch-hole

the frame used as a sync point; a hole punched into a frame of film

raster

a digital image consisting of regularly arranged pixels, usually rectangular

rasterise

the process of converting a non-raster image to a raster image

real-time

footage processed at the same speed actual frame-rate

re-conform

to take an existing conformed sequence and apply changes to it, usually automatically

reel

a single unit of footage, such as a videotape or reel of film; a collection of shots; a part of an output production

registration

the positioning of an image within a frame

release print

a film print that is used by cinemas for projection

re-master

to take a programme that has already been mastered and create a new master

render

the process of applying changes to an image; processing image data; outputting digtal images

render farm

a group of computers used for rendering

resample

to up-sample or down-sample an image; to re-digitise an image from its source, usually at a different resolution

resolution

the spatial detail of an image; the number of pixels in a digital image; the number of lines in a video image

resolution-independent

an image that can be of any resolution; a system that allows images of different resolutions to be conformed together

resolving power

the measurement of a system’s resolution

reversal film

film material that records a positive image directly from a source

RGB

a colour model combining proportions of red, green and blue together

ringing

the effect produced when images have been artificially sharpened too much

rotoscope

the process of generating masks or mattes for every frame in a sequence; the result of this process

rushes

see “dailies”

safe area

a region within an image where elements are generally guaranteed to be visible across different display devices

sampling ratio

in video, the ratio of different colour components, typically Y:U:V or Y:I:Q

saturation

the purity component of a colour

scene

an environment used for filming; a collection of shots within a particular location or timeframe

scrambling

a type of encryption that modifies all or part of the visible image, typically obscuring details

SD

see “standard definition”

secondary grading

the process of adjusting colour in selected parts of an image

seek

to go to a specific point in a timeline or data

selective grading

see “secondary grading”

sequence

a collection of shots and/or individual images

sharpen

a process used to exaggerate edges

shoot & protect

a method of shooting onto a particular aspect ratio, but ensuring that other aspect ratio images can later be extracted

shot

a collection of images, typically comprising continuous action without transitions; to have recorded something

shuttle

to progress through footage at a multiple of real-time

signal-to-noise ratio

the ratio of image information to inherent noise within a system

silver halide

the light-sensitive crystals within film material

slate

a description of a sequence, typically an image at the start or end of the sequence

soft cut

a transition involving a very brief dissolve

splice

to insert a shot between two other shots; a method for joining to pieces of fiolm together; the point at which a join has been made to film material

spread function

an objective measurement of image sharpness

sprocket

see “perforation”

stabilise

the process used to remove random motion in an image sequence, to steady it

standard definition

video format with low (“standard”) resolution

standards conversion

the process of converting between different video standards

still image

a single image, either from a sequence or not

streaming

the process of transmitting data for instant viewing

sync

synchronisation; whether two or more different sources match in terms of timing

sync pulse

part of a video signal that indicates the end of a line of picture; part of the video signal that indicates the end of a field

tape to tape

the process of transferring material from a source tape directly onto a record tape

TB

see “terabyte”

telecine

the process of transferring film material to video

terabyte

1024 gigabytes

thumbnail

a small copy of an image for fast previewing

timecode

a method for identifying and counting individual frames in a sequence, typically dependent on frame-rate to provide values applicable in real-time

timecode break

a discontinuity in timecode in a sequence

timeline

a method for displaying an edited programme visually; a sequence or programme

time-stamp

the recorded time and date on a file

timewarp

the ability to adjust the speed of a shot; a shot that has undergone this process

title safe

the safe area defining where titles can be seen

tone-map

the process of converting an HDR image to a specific colour space

tracking

the process of tracking the motion of a feature in an image sequence, usually to allow other elements to be attached to it

tracking marker

an object placed in a scene during shooting to allow tracking later on

tramline

a persistent scratch across a number of film frames, typically vertical

transcode

modifying image data to allow encoding to a different format

transition

a method from going from one shot to another

unsharp mask

see “sharpen”

up-rez

see “up-sample”

up-sample

to increase the number of pixels in an image, usually by interpolation

variable bit-rate

a data stream with varying bandwidth requirements; a compression method using varying bandwidth requirements

VBR

see “variable bit-rate”

VCR

see “video tape recorder”

vector

a mathematical shape

vectorscope

a method for displaying the chromacity content of an image; a device used to do this, usually for video signals

vertical interval timecode

a method for recording timecode as part of the video signal

VHS

see “video home system”

video cassette recorder

see “video tape recorder”

video home system

consumer-grade analogue video format

video tape recorder

a device for recording and playing video tapes

video-safe colour

see “legal colour”

video-switching matrix

a device that allows video to be routed to many different places at the same time

vignette

an effect caused by light distributed unevenly across the lens; a process mimicking this effect

VITC

see “vertical interval timecode”

VTR

see “video tape recorder”

warp

to alter the shape of all or part of an image

watermark

a visible image, typically a logo, placed over all images in a sequence; information embedded imperceptibly into an image

waveform monitor

a method for displaying the luminance content of an image; a device used to do this, usually for video signals

widescreen

an image format with a wide aspect ratio, typically wider than 4:3

wipe

a transition involving revealing one shot over another

YIQ

colour space used by the NTSC video format, encoding luminance and two chromacity components

YUV

colour space used by the PAL video format, encoding luminance and two chromacity components

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Posted: May 29th, 2005