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Glossary: Post Production
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2K
Short for the image size of 2048 x 1556 pixels. Commonly used resolution for digitising full frame
35mm film for visual effects and Digital Intermediate.
3:2 Pull-down
Telecine process used to create 60 fields [30fps] for 525/NTSC video from 24fps film material. The first film frame is repeated to create two fields and the subsequent frame is repeated three times. [12 frames x 2 = 24, 12 frames x 3 = 36, equals 60 fields.] This keeps the film duration the same for the Theatrical and TV versions.
4K
Short for the image size of 4096 x 3112 pixels. Higher resolution scan used for digitising full frame 35mm film for visual effects and Digital Intermediate.
525
Short for 525 line/59.94Hz component system used in USA and Japan. [See Component]
625
Short for 625 line/50Hz component system used in UK, Europe, Australia and other parts of the world. [See Component]
Aa
Analogue
Method of recording pictures or audio using a variable voltage level signal. The signal degrades on each generation.
Anamorphic
Commonly used to refer to the horizontal squeezing of a widescreen (e.g. 16:9) picture so that it can be recorded using a 4:3 tape format.
ARC – Aspect Ratio Converter
Equipment used to change the aspect ratio of TV images. Common examples are producing 4:3FF or 4:3 LB 1.55:1 (14:9) from a 16:9 Master.
Aspect Ratio
The shape of the TV or Film image expressed as units of width against units of height. ‘Old’ TV pictures are 4:3 [sometimes referred to as 12:9]; widescreen TV is 16:9. Current feature films are usually 1.85:1 (17:9) or 2.35:1 (21:9).
Auto Conform
Process of recreating the offline edit in an online suite from the master rushes using the timecodes contained in the EDL file.
Bb
Best Light
The Telecine transfer of film to tape, usually carried out in one pass with grading adjustment made on the fly. Mostly used for rushes transfers. Often confused with Technical Grade.
BITC – Burnt In Timecode
Master timecode that is displayed in the image to which it refers. Often used on viewing VHSs to provide accurate frame references.
Blue Screen
[See Chroma Key]
Cc
Centre Cut Out
To make a 14:9 Letterbox or 4:3 Full Frame image from the middle of a 16:9 widescreen master, with the loss of image from the sides.
Chroma Key
The process of shooting against a coloured background [normally green or blue], which is removed electronically in post production to allow the foreground to be placed over any background.
Chrominance
The colour part of a TV signal that relates to the hue and saturation but not the brightness of the displayed image.
Closed Caption
Information that is recorded in a non-visible part of TV image that can be read by a Closed Caption Reader to generate subtitles on the viewers television set.
Colour Correction
[See Grade]
Compression
The processes of reducing the amount of information required to record or transmit images and/or audio. The final quality will depend on the amount of compression applied – the lower the compression [higher data rate] used the better the final quality. Higher compression [lower data rate] will result in poorer quality.
Component Signal
A component video signal has separate luminance and chrominance information. This results in a better quality picture than a composite signal. HDCAM, HD D5, Digital Betacam, DVCPro, Betacam SP and D1 are examples of component formats.
Composite Signal
A composite video signal has combined luminance and chrominance information using one of three encoding standards – PAL, NTSC or SECAM. This results in a picture quality that is lower than component signals. 1-inch, D2 and VHS are examples of composite formats.
Compositing
Term referring to the combination of different picture elements and effects to produce a final “composite” image.
Conform
[See Auto Conform]
Cross Conversion
Changing video material from one high definition standard to another.
CSO – Colour Separation Overlay
A BBC term for Chroma Key.
Dd
DA-88/DA-98
8-track digital audio tape based on 8mm (Hi 8) tape – the format is actually called DTRS (Digital Tape Recording System).
DAT – Digital Audio Tape
2-track digital audio tape.
De-spot
The removal of film dirt and sparkle on Telecine transfers. Sometimes referred to as de-sparkle.
DF Timecode – Drop Frame Timecode
The process used to match the timecode on 525/NTSC masters. 525/NTSC is usually referred to as being 30fps, but actually runs at 29.97fps, thus the timecode drifts out in relation to ‘real time’. Drop Frame timecode overcomes this problem by skipping two frames every minute [except at every ten minute interval]; this brings the timecode back in line with ‘real time’.
Digital
Method of recording pictures or sound as a binary signal [ones and zeros]. The signal can be copied without any loss of quality.
Digital VTR
Video Tape Recorder that stores pictures and audio in digital form. Examples are D1, Digital Betacam, HDCAM, HD D5 and DVCAM.
Dissolve
Video transition where the outgoing picture is reduced in level to zero, whilst the incoming picture is increased in level from zero. Also known as a mix.
Dolby 5.1
Digital surround sound system, with separate front left and right and centre, rear left and right (5) and sub-bass channel (.1).
Dolby Surround
Analogue surround system with four audio channels – front left, centre, right and rear surround (mono signal) [LCRS] that are encoded into two channels, Left Total and Right Total [Lt, Rt]. These two signals are separated on playback by a Pro Logic decoder to give LCRS.
Down Conversion
Changing video material from a high definition format to a standard definition format.
Drop Out
Loss of picture and/or audio information resulting from damage or imperfections in the tape stock during recording or playback.
Dry-gate
Part of Telecine transport where the film is scanned by the Telecine (no fluid is used – see Wet-gate).
DTRS
See DA 88/98
Dust Bust
[See De-spot]
DVD – Digital Versatile Disk
A high-density storage format that is the same size as a CD. These are either single sided with single or dual layers or double sided with single or dual layers depending on the capacity. Most commonly used for storage of high quality video and audio. Sometimes mistakenly referred to as Digital Video Disk.
DVD-/+R
One time recordable DVD
DVD-/+RW
Rewriteable DVD
DVE – Digital Video Effects
Generic term for any piece of equipment that manipulates the shape, size, position and orientation of an image.
DVNR – Digital Vision Noise Reducer
Device made by Digital Vision for reducing or removing film grain and scratches or electronic noise from pictures. DVNR is often used to describe other noise reduction/dirt removal devices. Excessive use can create disagreeable artifacts.
Ee
EDL - Edit Decision List
Offline edit decisions saved as a computer file, usually on floppy
disk for use in an online session to auto-conform the offline edit at online quality.
Ff
FHA Full Height Anamorphic
[see Anamorphic]
Field
A TV frame is made up of two different interlaced fields, each of which is displayed for half the duration of the frame. The first field comprises the odd lines, the second field the even lines.
Filmic Effect
Filmic effect combines the two different fields of a television frame into a single frame to reduce the number of images displayed per second. This gives specifically shot material a visual quality similar to film.
Flex File
Data file that is created during the film rushes transfer that relates the keycode numbers from film to the timecode of the rushes tapes. Necessary if the film is going to be cut.
fps
Frames per second - the number of complete images displayed per second.
Frame
A Television frame is made of two interlaced fields. A film frame is a complete image representing an interval of time representing the inverse of the film speed [e.g. if shooting at 24fps, then each frame is 1/24th of a second].
Gg
Gamut
If something is said to be ‘out of gamut’ it contains colours which are ‘illegal’ when converted into the RGB domain.
Garbage Matte
A rough matte uses to remove unwanted objects such as lamp stands, wires and rigs from chroma key and visual effects sequences.
Grade
The process of changing the colour balance of an image, either to create a dramatic effect or to match the scene with others in the sequence of the film. Usually carried out in Telecine, but limited grading can be achieved in online suites.
Grade 1 Monitor
Very high quality monitors made to very high specifications. These can be accurately aligned to industry standards, thus enabling pictures displayed on different monitors to match.
Green Screen
[See Chroma Key]
Hh
Handles
Additional material before the in-point and after the out-point of a shot, that is loaded into an edit system to allow cut points to be extended if required.
HD – High Definition
Television format offering increased resolution compared to standard definition television. It also has a native aspect ratio of 16:9. Currently being transmitted in USA and Japan.
Hz – Hertz
Engineering term for number of cycles per second. Usually refers to number of images per second, 50Hz for 625/PAL and 60Hz for 525/NTSC.
Ii
Illegal Colours
Luminance or Chrominance levels that fall outside of the limits defined for each format. These can cause problems during transmission as well as playback. Colours that are legal in one video format can become illegal once converted to another video format.
Interlace
Video scanning where each frame is made up of two fields, each of which makes up half of the image. The first field comprises odd numbered lines, whilst the second field is made up of even lines.
Kk
Keycode
Numbers and barcodes along the edge of film that identify each film frame and can be automatically read by Telecine and negative cutting equipment. Used to relate each film frame to each video frame during rushes transfer and subsequent editing.
Key Frame
Markers within an effects sequence that are used to adjust the profile of any transition.
Keying
Layering of different picture elements using either a separate matte or by creating a matte using the luminance or chrominance content of the foreground image.
Ll
Letterbox
Method of displaying or recording pictures with a wider aspect ratio than that of the display screen. The image has black bars top and bottom.
Linear Editing
Tape-based system where scenes are laid down in order on tape. If a scene is changed in duration, then all the following material must be laid down again.
LTC – Longitudinal Timecode
Timecode that is recorded along the tape that is read when the tape is at play speed or greater i.e. when being shuttled at high speed.
Mm
Matte
A separate [usually] black and white signal that is used to separate parts of the image during compositing.
Motion Control
Computer controlled camera that can be programmed to follow a specific path for special effects shots. The move can be accurately repeated each time to allow each path to be overlayed.
MPEG – Moving Picture Experts Group
Compression standard for moving pictures. MPEG1 uses a high compression rate and is usually used for CD Rom, whilst MPEG2 has a lower compression rate [and hence better quality] and is used for DVD, video on demand and Digital Television transmission. Newer standards include MPEG3 (or MP3) used for audio and MPEG4 which is one of the standards being considered for high definition transmission.
Nn
NDF – Non Drop Frame
Timecode that identifies every frame of 525/NTSC material. As these systems operate at 29.97fps, the 30fps Non Drop Frame timecode will slowly drift from actual running time – by 18 frames every ten minutes.
Non-Linear Editing
Method of editing using disk storage, where scenes can be played back in any order or length. Shot durations and positions can be changed without having to replace the following material.
NTSC – National Television Standards Committee
Composite encoding system used for recording and transmission in USA, Canada and Japan. NTSC is often incorrectly used to refer to 525 component formats.
Oo
Offline
Editing process using lower cost, lower quality equipment, where the structure of the programme is created. The offline system then produces an EDL which is used in an online suite to recreate the programme from the master rushes.
OMFI – Open Media Framework Interchange
Standard for interchange of video and audio media between different applications and equipment, e.g. transferring audio media from an edit system to the dubbing theatre.
One Light
Transfer of film material where the grading is established on the first shot then all the material is transferred using these settings. Commonly used for rushes transfers.
Online
Higher cost editing systems using the EDL produced in the offline to reconstruct the programme using the full quality rushes material. Also when all dissolves, effects and titles are added.
Opengate
Method of transferring entire exposed negative, which may include more information than will end up on the finished version. The material will have been framed by the cameraperson in the required ratio e.g. framed for 2.35:1 within the super 35mm negative area.
OSC/R – Overlength Selected Cut Reels
Software system that references the film’s keycode numbers to the video’s timecode. Using the offline EDL, OSC/R will produce a list of keycode references that are used to cut the negative.
Overlength
Cut negative [usually S16mm] that has been assembled into programme order with 20 frame handles at each cut.
Pp
PAL – Phase Alternate Line
Composite encoding system used for recording and transmission in UK, Europe and Australia. PAL is often incorrectly used to refer to 625 component formats.
Perf
Short for perforation, used to transport the film through the camera or Telecine gate (also known as Sprocket).
Pillar box
Method of displaying or recording pictures with a narrower aspect ratio than the display format. The image has black bars at the left and right of picture.
Plate shot
The separate background element used in a chroma key effect shot.
Plug Ins
Third party software that adds extra functions to computer applications. Used to add specific effects not offered by the original manufacturer.
Pre-read
Recording technique on suitably equipped VTR [e.g. digital Betacam] where the source pictures or sound is played back, manipulated and recorded back on the same machine.
Progressive
Video standard where each line of the frame are displayed continuously from top to bottom in one pass. There are no fields as used in interlaced systems.
Progressive Segmented Frame (PsF)
This is where the progressive frame is split up into two segments, one containing the odd lines of the picture and the other the even lines, for recording on tape and display on a monitor.
Promist
A camera or Telecine filter that adds a diffusing effect to the picture. A similar effect can be created electronically in some online suites.
Rr
Real Time
Any operation that can be achieved in the running time of the material to which it is being applied.
Rendering
Process that is required when effects cannot be created in real time. The duration required to produce the final rendered version [that can be played in real time] depends on how complex the effect is.
Resolution
The measure of the finest detail that can be reproduced by the television system being used.
RGB
Red, Green and Blue. These are the primary colours from all others are derived in any television system.
Ss
Safe Action Area
The part of the picture that is considered to be the area that is visible on a correctly adjusted domestic television.
Safe Title Area
The area inside of safe action where critical elements such as text and graphics are placed, thereby ensuring they are not lost on a poorly adjusted television.
SD – Standard Definition
Television formats such as 625/PAL or 525/NTSC.
SECAM – Sequential Colour and Memory
Composite encoding system used for transmission, mainly in France. It is only relevant as a transmission standard and not used in post production.
Shoot and Protect
Widescreen shooting technique where critical action is framed more centrally, therefore making the widescreen master suitable for transmission in other aspect ratios.
Stabilise
Electronic method where unwanted movement, such as film weave or camera shake is removed from an image. To achieve this, it is necessary to slightly zoom into the original picture.
Standards Conversion
Process of changing from one television standard to another. This may require a number of format changes including either the removal or creation of lines and a change of frame rate, again by either removal or creation.
Striped Stock
Tape stock that has been prerecorded with black and timecode. This is needed for insert editing.
Tt
Tape Grade
Colour correction that is performed from a master tape rather than film elements. To get the best results, the material to be graded will be created from technically graded rushes.
Technical Grade
The Telecine transfer of film to tape, where the material is adjusted to ensure as much of the original image is maintained without any crushing of the blacks or whites. This material will later be auto conformed and tape graded to produce the final master.
Telecine
Machine used to transfer film to tape in real time. Each frame of film is scanned and converted into the required video standard. Used in conjunction with a colour corrector to create the final look of the material.
TIFF [.TIF]
Short for Tagged Image File Format. A bit-mapped file format used widely used for image transfers.
Time Lapse
Shooting technique where a very slow film speed is used [e.g. 1-frame per hour]. When played back at normal speeds, gives the impression of time being speeded up.
Timecode
A unique number given to each video frame, comprising of hour, minutes, seconds and frames. Used to identify each frame as well as required for accurate editing.
Timeline
A graphical representation of an editing sequence, showing each edit and its duration along a line representing time.
Uu
Underscan
Mode of operation for broadcast monitors, where the entire picture area, including that normally cropped by domestic television sets, can be displayed.
Up Conversion
Process whereby a standard definition image is formatted for display via a High Definition system. However this will never be the same quality as producing an original HD master.
Up-res
Process where the number of pixels used to represent an image is increased by interpolating the existing pixels, to produce a larger format. This process does not increase the resolution above that of the original image.
Vv
Vari-speed
Effect where the speed of film or video material is either increased or decreased, usually for creative reasons. This can be carried out in either a linear way across the whole scene, or gradually increased or decreased to give a smoother transition.
Vertical Interval
Non-visible part of TV image used for additional information, such as Timecode or ‘closed’ Subtitles.
Vistavision
Film format where the 35mm negative is passed through the camera horizontally rather than vertically, thereby increasing the negative area available and with it the resolution of the image. Usually used for effects shots.
VITC – Vertical Interval Timecode
Timecode that is recorded within the non-visible part of the picture. Unlike Longitudinal Timecode, VITC can be read when the tape is stationary.
VTR
Abbreviation for Video Tape Recorder.
Ww
Warp
Process where all or part of the frame is distorted as if it were an elastic surface.
Wet-gate
Telecine gate where the film is submersed in a solution whilst it passes through the optical path. The solution has the same optical properties as the film and helps to disguise any scratches during the transfer. It also helps to remove any dirt that might be present on the film.
Widescreen
Term used to refer to pictures wider than 4:3. Usually used to describe 16:9 television but also applies to 1.85:1 or 2.35:1 film aspect ratios.
Xx
X Axis
Denotes horizontal axis of a picture; to move a picture in the X axis is to move it left or right.
Yy
Y Axis
Denoted the vertical axis of a picture; to move a picture in the Y axis is to move it up or down.
Zz
Z Axis
Denotes the central axis of a picture; to move a picture in the Z axis is to move towards or away from the viewer.
Thanks to Pepper for compiling this glossary
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