PAL	Phase Alternate Line. Video standard in the United Kingdom and much of Europe. Comprised of 625 lines at 50Hz. Superior colour stability and resolution compared with NTSC.
pan and scan	A technique for selecting the critical areas of an image when converting from wide screen to standard ratio formats, eg transferring films to video.
pixel	Picture Element. A definable location on a screen, consisting of a triad of phosphor dots (red, green, blue). Also, the resolution of an image is expressed by the number of pixels present, eg high definition video can be 1920x1080 pixels, compared with standard definition video at 720x576 pixels, a 5-fold increase in resolution.
Proc Amp	Processing Amplifier. A device that stabilizes the video signal.
progressive scan	Capturing one frame of video in a single pass, rather than as two passes of interlaced line sets. Approximates the way film is exposed.
quantising	Sampling an analogue signal in an A/D conversion. 8 or 10 bit sampling is standard for video, 16 bit for audio.
QuickTime	A frequently used file format for storing video (and audio, if required) information in computer. Devised by Apple as an alternative to AVI.
quilting	Artefacting revealing visible blocks or boundaries of groups of pixels.
raster	The array of pixels that form an image.
raster transform	An algorithm that allows remapping of the raster from one form of coded representation to another, eg transcoding 4:2:0 video to 4:1:1 video.
real-time	In NLE systems, operations that require negligible time for rendering.
record-run timecode	Timecode triggered on/off by recording start/stop, generally from central clock linked to all devices. Generates continuous timecode values on tape. See 'free-run timecode'.
rendering	Recalculating individual pixels in an image to create effects or transitions during editing. Can be time consuming.
resolution	The density of lines or dots that make up an image. Limits the detail that can be held in the image.
RGB	Red, Green, Blue. One form of expression of a component video signal.
RMS voltage	Root Mean Square voltage. A measure of effective (as opposed to peak) AC voltage.
RS-232	A serial digital interface standard specifying 'unbalanced' voltage communication between D-type connectors. A control cable for a VTR will typically connect to this socket on an NLE computer (the serial port).
RS-422	A serial digital interface standard specifying 'balanced' voltage communication between D-type connectors. Typically used for the control cable socket on a VTR. An adapter is required to connect through to the RS-232 socket on a computer.
RS-422A	A Sony modification of the RS-422 protocol. Not necessary compatible with RS-422.
R-Y	One of the two colour difference signals in a component video signal, obtained by subtracting luminance from the red camera signal. R-Y signal drives the vertical axis of a vectorscope.
safety	The outer edges of a full video frame not seen on an a standard television.
SCSI	Small Computer Systems Interface. High speed computer component connection. Usually required in NLE to ensure smooth video playback. Four main types of increasing capacity: Fast (10MB/s, 8 bit), Ultra (20MB/s, 8 bit), Fast Wide (20MB/s, 16 bit), Ultra Wide (40MB/s, 16 bit).
SDI	Serial Digital Interface, offering uncompressed digital component video, four audio channels, timecode and user data. Supports data rate of 270Mb/s.
SECAM	Sequentiel Couleur Avec Memoire. Video standard in France and parts of Eastern Europe, Africa and Asia. Similar to PAL, but with the potential to eliminate the need for colour control. Comprised of 625 lines at 50Hz.
set-up level	Black Reference or Black Level. The specified voltage base of the active signal. Usually 7.5 IRE units above blanking (zero voltage).
SMPTE	Society of Motion Picture and Television Engineers
S/PDIF	Sony/Phillips Digital InterFace. Transmission format for digital audio, now outdated. Typically unbalanced.
subpixel	A unit smaller than a pixel. Can be significant in enhancing render quality.
S-VHS	Super Video Home System or Super VHS. A higher quality version of VHS.
S-Video	A composite video signal separated into Luminance (Y) and Chrominance (C).
TBC	Time Base Corrector. A device that generates new control pulses in degraded original data. Used to clearly define vertical lines in a frame.
telecine	An expensive device for transferring film to video.
timecode	Recorded time information to allow synchronization of devices. Usually an eight digit number specifying hours: minutes: seconds: frames of a video sequence.
transcoder	A device that converts one form of encoded video to another, eg to convert PAL video to NTSC.
timeline	On a computer, the area of an NLE software interface which displays video and audio clips laid in sequence. It also displays where transitions, effects or titles are laid.
transition	An editing effect which specifies the transition from one video clip to the next.
unbalanced	Unshielded voltage connection suitable only for short cables as it is prone to interference.
underscan	On a monitor, revealing the whole of a recorded video image including the 'safety'.
vectorscope	A generic name for a display allowing visual checking of the phase and amplitude of the colour components of a video signal. Software simulations are available for NLE.
vertical resolution	Chrominance and luminance detail expressed vertically in the image. Limited by the number of scan lines.
VITC	Vertical Interval Time Code. Time code encoded into the vertical interval of the video signal.
VTR	Video Tape Recorder
waveform monitor	An oscilloscope designed for viewing the waveform, and checking the components, of a video signal.
XLR	Generic term for Cannon 3 pin circular connector for balanced audio.
Y, R-Y, B-Y	Components of a the highest quality video signal. 'Y' corresponds to the luminance, 'R-Y' corresponds to the red minus luminance signal, 'B-Y' corresponds to the blue minus luminance signal.
Y/C	Video signal composed of luminance, 'Y', and chrominance, 'C'. S-VHS quality.
YUV	Component video signal composed of luminance, 'Y', and colour difference, 'U' and 'V'. Betacam quality.