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, 3 fields, 2 fields, etc. (see also A-frame)
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).
4:4:4
A sampling ratio that has equal amounts of the luminance and both chrominance channels.
4fsc
Composite digital video as used in D2 and D3. Stands for four times the frequency of subcarrier which is the sampling rate used.
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.
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.
Film frame A = video fields 1 & 2,
Film frame B = video fields 1 & 2 & 1,
Film frame C = video fields 2 & 1,
Film frame D = video fields 2 & 1 & 2.
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.
Aliasing
Defects in the picture caused by too low a sampling frequency or poor filtering. Usually scene as "jaggies" or stair steps in diagonal lines.
Artefact
A visual effect caused by an error or limitation in the system.
Anti-aliasing
The process of removing aliasing artefacts.
Aspect Ratio
The ratio of width to height in a picture. Theatre screens generally have an aspect ratio of 1.85 to 1, widescreen TV (16x9) is 1.77 to 1, and normal TV (4x3) is 1.33 to 1.
Auto Assembly (Auto Conform)
An edit in which the off-line edit decision list is loaded into the on-line edit computer and all the edits are assembled automatically with little human intervention.
Blanking
The part of the video signal that contains no picture information.
Blu-ray DVD
Blu-ray DVD (also known as BD) is an optical disc storage media format. Its main uses are high-definition video and data storage. The disc has the same physical dimensions as a standard DVD or CD. The name Blu-ray Disc is derived from the blue laser (violet colored) used to read and write this type of disc.
Burnt in Time Code
Time code numbers that is superimposed on the picture.
CBR
Constant Bit Rate. MPEG video compression where the amount of compression does not change.
CCIR 601
The standard for digitizing component video. Also sometimes called D1 after the VTR format that first used this signal.
Chrominance
The colour part of a video signal.
Component Video
A video signal in which the Luminance and Chrominance signals are kept separate. This requires a higher bandwidth, but yields a higher quality picture.
Composite Video
The luminance and chrominance signals are combined in an encoder to create the common NTSC, PAL or SECAM video signals. Essentially a form of analogue video compression to allow the economical broadcasting of video.
Compression
The process of reducing the size of digital information, usually by throwing out redundant information.
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.
Control Track
A signal recorded on videotape to allow the tape to play back at a precise speed in any VTR. Analogous to the sprocket holes on film.
CRT
Cathode Ray Tube. The technical name for a picture tube or the scanning tube in a flying spot telecine.
D1 (Sony)
Digital videotape format using the CCIR 601 standard to record 4:2:2 component video on 19mm tape. The first digital videotape format, hence D1.
D2 (Sony)
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 videotape format, hence D2.
D3 (Panasonic)
Digital videotape 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 (Panasonic)
Digital videotape format using CCIR 601, 4:2:2 video. Uses the same cassette as D3.
D5 HD (Panasonic)
High Definition Digital videotape supports various frame rates including 60i, 50i, 60P, 25P and 24P. Uses the same cassette as D5.
D6
D6 is currently the only HD recording format defined by a recognized standard. The Thomson Voodoo Media Recorder is based on D6 technology.
D7
This has been assigned to DVCPRO.
D8
Uses 8mm or Hi8 tape to record images digitally.
D9
This is assigned to Digital-S. Digital-S uses a cassette with the same basic shape and exterior dimensions as S-VHS.
D10 -IMX
MPEG IMX is a 2001 development of the Digital Betacam format. It uses the MPEG compression system, but at a higher bitrate than Betacam SX. The IMX format allows for a CCIR 601 compliant video signal, with eight channels of audio and timecode track.
DCT
Discrete Cosine Transform. A widely used method of video compression. Also an Ampex CCIR 601 digital VTR using DCT to compress the video before recording it to tape.
Digital
A form in which everything is defined by a series of ones and zeros.
Digital Betacam
Digital videotape format using the CCIR 601 standard to record 4:2:2 component video in compressed form on ˝" tape.
Digital intermediate (DI)
Digital intermediate (often abbreviated as DI) describes the process of digitizing a motion picture and manipulating colour and other image characteristics to change the look, and is usually the final creative adjustment to a movie before distribution in theaters.
DDR
Digital Disk Recorder. A digital video recording device based on high speed computer disk drives. Commonly used as a means to get video into and out from computers.
Digitizing
The act of taking analogue video and converting it to digital form.
DVD
Digital Versatile Disc. A format for putting full-length movies on a 5" CD using MPEG-2 compression for "better than VHS" quality.
DVE
Digital Video Effects. Common DVE effects include inverting the picture, shrinking it, moving it around within the frame of another picture, spinning it, and a great many more.
Edge Numbers
Numbers printed on the edge of 16 and 35mm motion picture film every foot, which allows frames to be easily identified in an edit list.
EDL
Edit Decision List. A list of edit decisions made during an edit session and usually saved to floppy disk. Allows an edit to be redone or modified at a later time without having to start all over again.
Field
One half of a complete video picture (frame), containing all the odd or even scanning lines of the picture.
Flex
File
A computer generated file that keeps track of 3 different codes and other information at any given point. Most importantly, this file establishes the relationship of video time code to film Keycode, but can also include audio time code, (or AatonCode).
Frame
One complete video image. There are 30 frames in one second of NTSC video and 25 frames in one second of PAL video.
H.264
H.264 is a standard for video compression. H.264, aka MPEG-4 Part 10, contains a number of new features that allow it to compress video much more effectively than older standards.
HDCam (Sony)
High Definition Digital videotape. HDCAM format recording frequencies: 1080/59.94i, 29.97PsF, 50i, 25PsF, 24PsF and 23.98PsF.
Interlace
A process in which the picture is split into two fields by sending all the odd numbered lines to field one and all the even numbered lines to field two. This was necessary in the early days of TV when there was not enough bandwidth to send a complete frame fast enough to create a non-flickering image.
ISO image
An ISO image includes all the data of files contained on the archived CD/DVD, or any other disc format. They are stored in an uncompressed format. In addition to data of the files it also contains all the file system metadata, including boot code, structures, and attributes. The most important feature of an ISO image is that it can be easily burned to a DVD or CD by using an ISO image burner.
Keycode/Key numbers
A barcode on the edge of motion picture film. Keycode allows machines to electronically read key numbers as the film passes through a reader attached to the Telecine. Keycode/key numbers act as a sort of time code for film, providing location information as well as film stock type and batch codes. Very useful for generating a negative cut list from a video off-line EDL.
LTC
Linear Time Code. Time code recorded on a linear analogue track on videotape.
Letterbox
Placing a wide screen image on a conventional TV by placing black bands at the top and bottom of the screen.
Luminance
The black and white, or brightness, part of a component video signal.
MPEG
Moving Picture Experts Group. A standard for compressing moving pictures.
MPEG 1 uses a data rate of 1.2 Mbps (Mega Bits per Second), the speed of CD-ROM.
MPEG 2 supports much higher quality with a data rate (also called bit rate) of from 2 to 10 Mbps. MPEG 2 is the format most favoured for video on demand and DVD.
MPEG-4 is still a developing standard and is divided into a number of parts.
NTSC
National Television Standards Committee. Consists of 525 horizontal lines at a field rate of 60 fields per second. (Two fields equal one complete Frame).
PAL
Phase Alternating Line. Consists of 625 horizontal lines at a field rate of 50 fields per second. (Two fields equal one complete Frame).
Pixel
Short for Picture Element. The basic unit from which a video or computer picture is made. Essentially a dot with a given colour and brightness value. D1 images are 720 pixels wide by 486 high. NTSC images are 640 by 480 pixels.
Resolution
The amount of detail in an image. Higher resolution equals more detail. Also used to describe the size of an image, usually in pixels.
Re-wash
Film can be re-cleaned by running it through part of the film processing machine again. This softens the emulsion of the film to remove embedded dirt. Re-washing is more thorough than an ultrasonic film cleaning, but is only performed by a film lab on an as needed basis.
RGB
Red, Green, Blue. The primary colours of light. Computers and some component devices use separate red, green, and blue colour channels to keep the full bandwidth and therefore the highest quality picture.
Sampling Frequency
The number of sample measurements taken from an analogue signal in a given period of time. These samples are then converted into numerical values stored in bytes to create the digital signal.
SECAM
Systeme Electronique Couleur Avec Memoire. Consists of 625 horizontal lines at a field rate of 50 fields per second. (Two fields equal one complete Frame).
Time
Code
SMPTE/EBU time code is a binary code, which becomes an embedded part of a picture or sound recording and assigns a specific address to each moment of time in a recording.
Ultrasonic
Film Cleaner
A device that runs film through a heated bath of fluid which is vibrated at ultrasonic frequencies. Jets of fluid and swirling buffers add to the cleaning power. Finally, the film is run through a heated air dry system before winding onto a take-up reel.
VBR
Variable Bit Rate. MPEG video compression where the amount of compression does change depending on the complexity of the scene.
VITC
Vertical Interval Time Code. Timecode stored in the vertical interval of the video signal. Has the advantage of being readable by a VTR in still or jog. Multiple lines of VITC can be added to the signal allowing the encoding of more information than can be stored in normal LTC.
WMV - Windows Media Video
Windows Media Video (WMV) is a compressed video file format for several proprietary codecs developed by Microsoft. The original codec, known as WMV, was originally designed for Internet streaming applications.
YUV
YUV, also known as Y'CbCr and YPbPr, is a colour space in which the Y stands for the luminance component (the brightness) and U and V are chrominance (colour) components. It is commonly used in video applications, where it is also referred to as component video.