Glossary of Technical Film and Broadcasting Terms

ITU Standards

ITU624-4
The standard for analog PAL (625 line) broadcasting signals. Equivalent to the NTSC (525 line) SMPTE ST 170 standard
ITU-R BT470
An international standard for the PAL composite analog television system
ITU-R601
An international standard for component digital television from which was derived SMPTE ST 125 and EBU 3246-E standards. ITU-R601 defines the sampling systems, matrix values and filter characteristics for both Y, B-Y, R-Y and RGB component digital television signals. This document was formerly known as CCIR-601. and may be referred to informally as 601 or Rec 601
ITU-R656
The physical parallel and serial interconnect scheme for ITU-R601. ITU-R656 defines the parallel connector pinout as well as the blanking, sync and multiplexing schemes used in both parallel and serial interfaces. It reflects definitions found in EBU TECH 3267-E (for 625 line systems) and SMPTE ST 125 (parallel 525 line systems) and SMPTE ST 259 (serial 525 line systems). This document was formerly known as CCIR-656
ITU-R709
An international standard for high definition component digital television from which was derived SMPTE ST 274 and SMPTE ST 296 standards. ITU-R709 defines the sampling systems, matrix values and filter characteristics for both Y, B-Y, R-Y and RGB high definition component digital television signals. This document may be referred to informally as 709 or Rec 709

SMPTE Standards

SMPTE ST 12-1
The SMPTE standard for the Time and Address Control signal in widespread use in the professional video and audio industries. SMPTE ST 12-1 defines the specifications for both Linear Time Code (LTC) and Vertical Interval Time Code (VITC).
SMPTE ST 12-2
The SMPTE Recommended Practice for transmitting Time code in the ancillary data space of serial digital television signals
SMPTE ST 125
The SMPTE standard for bit parallel digital interface for component video signals. SMPTE ST 125 defines the parameters required to generate and distribute component video signals on a parallel interface for 525 line video systems
SMPTE ST 170
The SMPTE standard for the NTSC composite analog television signals
SMPTE ST 259
The SMPTE standard for the serial digital interface for standard definition 10 bit 4:2:2 component and 4Fsc composite interfaces. (Often referred to as SDI)
SMPTE ST 272
The SMPTE standard for embedding AES audio into standard definition serial digital interfaces
SMPTE ST 274
The SMPTE standard for HDTV 1920 x 1080 line scanning and analog and parallel interfaces for multiple frame rates
SMPTE ST 276
The SMPTE standard for transmission of AES digital audio over coaxial cable
SMPTE ST 291
The SMPTE standard for Ancillary Data Packet and Space Formatting
SMPTE ST 292
The SMPTE standard for the 1.485 Gb/s serial digital interface for High Definition television signals. (Often referred to as HD SDI)
SMPTE ST 293
Television - 720 x 483 Active Line at 59.94-Hz Progressive Scan Production - Digital Representation
SMPTE ST 296
The SMPTE standard for HDTV 1280 x 720 line progressive images - scanning and analog and parallel interfaces
SMPTE ST 299
The SMPTE standard for embedding AES audio into high definition serial digital interfaces
SMPTE ST 305
Television - Serial Data Transport Interface (SDTI)
SMPTE ST 309
The SMPTE standard for the encoding Date and Time Zone information into SMPTE ST 12-1 Time code signals
SMPTE ST 310
Television - Synchronous Serial Interface for MPEG-2 Digital Transport Streams
SMPTE ST 349
Television - Transport of Alternate Source Image Formats through SMPTE ST 292
SMPTE ST 372
The SMPTE standard for the dual link 1.485 Gb/s serial digital interface for High Definition television signals
SMPTE ST 424
The SMPTE standard for the nominal 3Gb/s serial digital interface for High Definition television signals
RP 168
The SMPTE Recommended Practice for the definition of the vertical interval switching point for synchronous video switching. This recommended practice also defines a default alignment between standard definition and high definition synchronizing pulse signals

Other Standards

AES3-1992
A digital audio standard defined in 1992 by the AES/EBU
AES3-2001
A digital audio standard defined and updated in 2001 by the AES/EBU
DVB-ASI
Digital Video Broadcast-Asynchronous Serial Interface. A standard definition digital video standard with a bit rate of 270Mb/s
EBU TECH 3267-E
The EBU recommendation for the parallel interface of 625 line digital video signal. This is a revision of the earlier EBU Tech 3246-E standard, which was in turn derived from ITU-R601
EIA-608
A Closed Caption standard for SD-SDI television signals
EIA-708
A Closed Caption standard for HD-SDI television signals
M2S
A digital video standard similar to DVB-ASI but using a different method to time incoming data packets. This limits the bit rate of M2S to 100Mb/s
RS-232
A common interface standard for serial data communications equipment
RS-422
A serial data standard which allows one transmitter to send communication data to up to 10 receivers
RS-485
A "party-line" serial data standard with up to 32 transmitters and receivers. Only one line transmitts data at a time while all other lines can receive simultaneously

Terms

1080p/24
A progressively scanned high definition video format with 1920 pixels and 1080 lines and a nominal frame rate of 24 frames per second (see also sF)
4:2:2
A commonly used term for a component digital video format. The details of the format are specified in the ITU-R601 standard. The numerals 4:2:2 denote the ratio of the sampling frequencies of the luminance channel to the two colour difference channels. For every four luminance samples, there are two samples of each colour difference channel
4:4:4
A commonly used term for a high resolution component digital video format. The numerals 4:4:4 denote the ratio of the sampling frequencies of the luminance channel to the two colour difference channels. For every four luminance samples, there are four samples of each colour difference channel. 4:4:4 sampled signals are also available in a RGB format with equal sampling rates for each of the colour channels. These signals are commonly carried on a pair of coax cables according to the SMPTE ST 372 standard
4Fsc
A commonly used term for a composite digital video format. The details of the format are specified in the ITU-R601 standard. The numerals 4Fsc denote that the sampling frequency is 4 times the colour subcarrier frequency (approximately 14.3 MHz for NTSC and 17.7 MHz for PAL)
AatonCode
An in-camera film timecode system, exposed in the camera during filming, carries data which is both machine-readable (a matrix of dots for each film frame) and man-readable for its conversion into SMPTE time code. AatonCode specifically contains the production timecode synchronizing data, hour, minute, second, frame, year, month, day, production ID, camera ID and camera speed. AatonCode, the original format and AatonCode II, the current format are both readable by Evertz UV series reader heads.
AES
Audio Engineering Society. AES is a professional organisation that recommends standards for the audio industries
AES / EBU
Informal name for a digital audio standard established jointly by the Audio Engineering Society and the European Broadcasting Union organisations. This audio standard is formally known as AES3 but may also be informally called AES/EBU audio or simply AES audio
AFD
Active Format Description. AFD is intended to guide DTV receivers and/or intermediate professional video equipment regarding the display of video of one aspect ratio on a display of another aspect ratio. It is specified by SMPTE standards 2016-1 and 2016-3
Afterburner
A device which takes embedded data from the video bit stream and translates it into human readable text. This text is then "burnt" into the on screen picture in character windows. This is usually time code data, scene, take and other post production data
Alpha channel
In electronic production and post-production, there is increasing application of 4:4:4:4 encoding ---- which provides full-bandwidth R', G', and B' plus the additional alpha channel to carry processing information. An adaptation from computer graphics, the alpha channel may contain information for linear key, for luminance and/or chroma transparency, for variable edge enhancement, and similar image-processing information
Analog
An adjective describing any signal that varies continuously as opposed to a digital signal that contains discrete levels representing digits 0 and 1
A to D converter (analog-to-digital)
A circuit that uses digital sampling to convert an analog signal into a digital representation of that signal
Analog Video / Analog Audio
A video or audio stream encoded into the voltage amplitudes of an electromagnetic wave
Aperature, camera
The available maximum dimensions of the optical image on the active surface of the photo-sensor, within which good quality image information is being recorded. The camera aperture determines the maximum usable scene information captured and introduced into the system, and available for subsequent processing and display
Aperature, clean
The clean aperture in a video digital system defines an inner picture area (within the production aperture) within which the picture information is subjectively uncontaminated by all edge transient distortions
Aperature, production
A production aperture for a studio digital video signal defines an active picture area produced by signal sources such as cameras, telecines, digital video tape recorders, and computer-generated pictures. It is recommended that all of this video information be carefully carefully produced, stored, and properly processed by subsequent digital equipment
Aperature, safe action
A safe action aperture indicates the safe action image area within which all significant action must take place, to ensure visibility of the information on the majority of home television receivers
Aperature, safe title
A safe title aperture indicates the safe title image area, within which the most important information must be confined, to ensure visibility of the information on the majority of home television receivers
ARRI Code
An in-camera film timecode system, exposed in the camera during filming, carries machine-readable data (a modulated series bars similar to SMPTE LTC for each film frame). ARRI Code specifically contains the production timecode data, hour, minute, second, frame, year, month, day, and camera ID. ARRI Code is readable by Evertz UV series reader heads.
Artifact
A defect or distortion of the image, introduced along the sequence from origination and image capture to final display
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
ATC
Ancillary Time Code. See SMPTE ST 12-2
Audio Group
A group of four audio signals embedded into a serial digital video bitstream. The group usually consists of either four monaural audio channels or two stereo pairs
Average Picture Level (APL)
In video systems, the average level of the picture signal during active scanning time integrated over a frame period; defined as a percentage of the range between blanking and reference white level
Balanced Audio
A method of transmitting audio that resists interference by sending a signal and its electrically inverse signal. Noise pickup along the transmission path is cancelled out as the two signals are differentially combined at the receiving end. This method of transmission is designed for long and/or exposed cable runs
Bar Data
Bar Data information is used to signal the precise unused areas of an image raster when the active video does not completely fill that raster, in particular widescreen cinema material carried letterboxed in a frame with bars top and bottom. AFD and Bar Data are described in a forthcoming SMPTE standard as well as ATSC A/53E (2006), CEA CEB-16 (2006)
Bit
A binary representation of 0 or 1. One of the quantized levels of a pixel
Bit error rate (BER)
The average probability of a digital recording system reproducing a bit in error. It is the ratio of the number of characters of a message incorrectly received to the number of characters of the message received
Bit Parallel
Byte-wise transmission of digital video down a multi-conductor cable where each pair of wires carries a single bit. This standard is covered under SMPTE ST 125, EBU TECH 3267-E and ITU-R656
Bit Serial
Bit-wise transmission of digital video down a single conductor such as coaxial cable. May also be sent through fiber optics. This standard is covered under SMPTE ST 259 and ITU-R656
Bit Stream
A continuous series of bits transmitted on a line
Bit-rate
The speed at which bits are transmitted, usually expressed in bits per second. With video information, in a digitized image for example, is transferred, recorded, and reproduced through the production process at some rate (bits/s) appropriate to the nature and capabilities of the origination, the channel, and the receptor
Blanking level
That level of a composite video signal that separates the range containing picture information from the range containing synchronizing information
BNC
Acronym for Bayonet Neill Concelman - a coaxial cable connector used extensively in professional television systems. These connectors have a characteristic impedance of 75Ω and are standardized by IEC 61169-8 Annex A
Byte
A complete set of quantized levels containing all the bits. Bytes consisting of 8 to 10 bits per sample are typical in digital video systems
Cable equalization
The process of altering the frequency response of a video amplifier to compensate for high frequency losses in coaxial cable
CCIR
International Radio Consultative Committee. An international standards committee. (This organisation is now known as ITU)
CEA
Consumer Electronics Association. CEA is a professional organization that recommends standards and practices for the U.S. consumer electronics industry
Cliff Effect
Also referred to as the 'digital cliff'. This is a phenomenon found in digital video systems that describes the sudden deterioration of picture quality due to excessive bit errors, often caused by excessive cable lengths. The digital signal will be perfect even though one of its signal parameters is approaching or passing the specified limits. At a given moment however, the parameter will reach a point where the data can no longer be interpreted correctly, and the picture will be totally unrecognisable
Closed Caption
A system of encoding word characters onto certain lines of a video stream which can be decoded and displayed by a compatible television. Provides program subtitles for the hearing impaired
CODEC
An acronym of Compression, Decompression. A device or piece of software which takes one file or signal format and translates it to another with an ideally undetectable loss of quality
Color Black
An analog video signal that displays a black screen. This signal is often used as a reference signal for timing purposes
Component Analog
The non-encoded output of a camera, video tape recorder, etc., consisting of the three primary colour signals: red, green, and blue (RGB) that together convey all necessary picture information. In some component video formats these three components have been translated into a luminance signal and two colour difference signals, for example Y, B-Y, R-Y
Component color
Structure of a video signal wherein the R, G, and B signals are kept separate from one another or wherein luminance and two band-limited color-difference signals are kept separate from one another. The separation may be achieved by separate channels, or by time-division multiplexing, or by a combination of both
Component Digital
A digital representation of a component analogue signal set, most often Y, B-Y, R-Y. The encoding parameters are specified by ITU-R601. ITU-R656 and SMPTE ST 125 specify the parallel interface
Composite Analog
An encoded video signal such as NTSC or PAL video that includes horizontal and vertical synchronizing information
Composite color
Structure of a video signal wherein the luminance and two band-limited color-difference signals are simultaneously present in the channel. The format may be achieved by frequency-division multiplexing, quadrature modulation, etc
Composite digital
A digitally encoded video signal, such as NTSC or PAL video that includes horizontal and vertical synchronizing information
CWDM
Coarse Wave Division Multiplexing. Coarse Wave Division Multiplexing allows up to 16 separate channels of data to be carried over a single optical cable using different wavelengths for each channel. Typically the wavelengths are separated at 20 nanometer wavelength intervals
D1
A component digital video recording format that uses data conforming to the ITU-R601 standard. Records on 19mm magnetic tape. (Often used incorrectly to refer to component digital video)
D2
A composite digital video recording format that uses data conforming to SMPTE ST 244. Records on 19mm magnetic tape. (Often used incorrectly to refer to composite digital video)
D3
A composite digital video recording format that uses data conforming to SMPTE ST 244. Records on 1/2" magnetic tape
D5
A component digital video recording format that uses data conforming to the ITU-R601 standard. Records on 1/2" magnetic tape
DARS
Digital Audio Reference Signal. A reference signal conforming to the format and electrical specification of the AES3 standard, but often has only the preamble active. This signal is used for synchronization in digital audio studio applications. The recommended practice AES11-1997 gives further information on the use of a DARS reference
Daylight saving time (DST)
Daylight Saving Time (DST) or Summer Time as it is called in many countries, is a way of getting more daylight out of the summer days by advancing the clocks by one hour during the summer. Then, the sun will appear to rise one hour later in the morning when people are usually asleep anyway, at the benefit of one hour longer evenings when awake. The sunset and sunrise are one hour later than during normal time
dB- (prefix)
A symbol indicating that a measurement is made using a logarithmic scale similar to that of the decibel (see below) in that a difference of 10 dB- corresponds to a factor of 10. In each case, the actual measurement is compared to a fixed reference level r and the "decibel" value is defined to be 10 log10(a/r). Many units of this kind have been used and only a few of the more common ones are mentioned in the next entries. In each case the dB symbol is followed by a second symbol identifying the specific measurement. Often the two symbols are not separated (as in "dBA"), but the Audio Engineering Society recommends that a space be used (as in "dB A")
dB FS
Abbreviation for "decibels full scale," a unit of power as measured by a digital device. A digital measurement has a maximum value M depending on the number of bits used. If the actual power measurement is p, the dB FS value displayed is 20•log10(p/M) dB FS. Since p cannot exceed M, this reading is always negative
dBm, dBW
logarithmic units of power used in electronics. These units measure power in decibels above the reference level of 1 milliwatt in the case of dBm and 1 watt in the case of dBW. A power of n watts equals 10 log n dBW; conversely, a power of p dBW equals 10(p/10) watts. The same formulas link dBm to milliwatts. An increase of 10 dB m or 10 dBW represents a 10-fold increase in power. Since 1 watt = 1000 milliwatts, 0 dBW = 30 dBm
dBu
A logarithmic unit of power, similar to dBm but computed from voltage measurements. The reference level is 0.775 volts, the voltage which generates a power of 1 milliwatt across a circuit having an impedance of 600Ω. A voltage of V volts corresponds to a power of 20•log10(V/0.775) dBu
decibel (dB)
A customary logarithmic measure most commonly used (in various ways) for measuring sound. The human ear is capable of detecting an enormous range of sound intensities. Furthermore, our perception is not linear. Experiment shows that when humans perceive one sound to be twice as loud as another, in fact the louder sound is about ten times as intense as the fainter one. For this reason, sound is measured on logarithmic scales. Informally, if one sound is 1 bel (10 decibels) "louder" than another, this means the louder sound is 10 times louder than the fainter one. A difference of 20 decibels corresponds to an increase of 10 x 10 or 100 times in intensity. The beginning of the scale, 0 decibels, can be set in different ways, depending on exactly which aspect of sound is being measured. See also dB- (above)
De-embedding
The process of extracting an embedded signal from an input stream to generate two separate signals, perhaps with different standards. This term is often used to describe the process of extracting AES audio that has been embedded onto a serial digital video signal
Demux
An abbreviation for 'de-multiplexing' which is the separation of Multiplexed data streams for dispersal to different devices. This term is often used synonymously with De-embedding when used to describe the process of extracting AES audio that has been embedded onto a serial digital video signal
Digital Video / Digital Audio
A video or audio stream encoded into binary digits instead of wavelengths and amplitudes
Distribution Amplifier
An electronic device which accepts a broadcast signal, amplifies it, and then outputs the same signal many times. Essentially a signal copying device
Downconverter
A converter which takes an HDTV signal and rescales it into a standard definition TV signal
Downstream
A broadcasting term meaning closer to the point of final transmission. Indicates the system is robust enough to handle "on-air" signals with confidence
Drop frame
A method of adjusting the nominal 30 frame per second counting rate of SMPTE ST 12-1 time code to the actual counting rate of approximately 29.97 frames per second - a difference of 1 part in 1001. This correction drops 108 frames per hour by skipping frame counts 0 and 1 at the beginning of each minute, except minutes 0, 10, 20, 30, 40 and 50. See also LTC and VITC
DWDM
Dense Wave Division Multiplexing. A method for combining multiple fiber optic signals of different wavelengths onto a single strand of cable in a much smaller wavelength spectrum than CWDM. Dense Wave Division Multiplexing allows up to 80 separate channels of data to be carried over a single optical cable using different wavelengths for each channel
EAS
Emergency Alert System. A broadcast warning system in the United States that either interrupts normal broadcasting, or displays an alert which crawls across the video picture. EAS alerts also contain an audible alert message
EAV
Abbreviation for "End of Active Video". A digital synchronization sequence consisting of a sequence of four consecutive code words (a code word of all ones, a code word of all zeros, another code word of all zeros, and a code word including F (field/frame), V (vertical), H (horizontal), P3, P2, P1, and P0 (parity) bits.) which is used to designate the start of the horizontal blanking interval of the digital line. See also SAV
EBU
European Broadcasting Union. EBU is an organisation of European broadcasters that among other activities provides technical recommendations for the 625/50 line television systems
EDH
Error Detection and Handling (EDH) is defined in SMPTE RP 165 as a method of determining when bit errors have occurred along the digital video path. According to RP 165, two error detection checkwords are used, one for active picture samples, and the other on a full field of samples. Three sets of flags are used to convey information regarding detected errors, to facilitate identification of faulty equipment or cabling. One set of flags is associated with each checkword, and the third is used to evaluate ancillary data integrity. The checkwords and flags are combined into a special error detection data packet that is included as ancillary data in the serial digital signal
Embedded Audio
Digital audio is multiplexed onto a serial digital video data stream according to the SMPTE ST 272 (standard definition) or SMPTE ST 299 (high definition) standards
Embedding
The process of combining one type of signal with another such that both signals can be transmitted using the standard of just one. This term is often used to describe the process of inserting AES audio into a serial digital video signal
Equalization
See Cable equalization
Ethernet
A protocol for connecting computers over a Local Area Network (LAN)
Fiber Optics
A method of encoding digital information into a pulsing laser, allowing much higher transmission bandwidth than copper cable
Film Time Code
See AatonCode, ARRI Code
Frame Synchronizer
A device which retimes an incoming video signal to a set reference such as genlock, bi-level or tri-level sync signals
GPI
General Purpose Interface. A method for communicating with electronic systems by utilizing relay or electronic contact closure inputs and outputs. This term may also be an acronym for General Purpose Input, which is the contact closure input of a General Purpose Interface
GPO
General Purpose Output. The contact closure output of a General Purpose Interface
GPS
Global Positioning System. A collection of 24 orbiting satellites operated by the US Department of Defense. Using signals transmitted to and from these satellites, electronic devices can pinpoint their location and the local time and time zone automatically
Graticule
A group of lines inserted over a video signal to allow for measurement and alignment of the image. In a film camera the graticule is ground into the glass of the optical viewfinder to allow the cinematographer to properly frame the image
HANC
Horizontal Ancillary Data. Acronym for ancillary data packets carried in the horizontal blanking intervals of a digital television signal. May also refer to the data space located in the horizontal blanking interval where these packets are carried. Ancillary data packets contain metadata associated with the video or audio of a television bitstream. See also VANC
HD-D5
A Panasonic HDTV component digital video recording format that uses data conforming to the ITU-R709 standard. Records on 1/2" magnetic tape
HDCAM
A Sony HDTV component digital video recording format that uses data conforming to the ITU-R709 standard. Records on 1/2" magnetic tape
HD-SDI
High Definition Serial Digital Interface. A bit-serial digital interface for HDTV component signals operating at data rates of 1.485 Gb/s and 1.485/1.001 Gb/s. The HD-SDI interface is standardized in SMPTE ST 292 and can be carried over coaxial and fiber optic cables
Hue
Attribute of a visual sensation according to which an area appears to be similar to one of the perceived colors, red, yellow, green, and blue, or to a combination of two of them
IF-band (70/140MHz)
A frequency band with two frequencies: 70MHz and 140MHz. Usually used by satellite studios to uplink to a satellite transmission system
Impedance
A measurement of opposition to electrical current exhibited by a circuit or device, taking into account resistance and AC reactance
Intercom
A system of internal audio communication within a building or corporation over a number of well-defined standards such as RTS-Telex and ClearCom
IRE units
A linear scale in arbitrary units developed by the Institute of Radio Engineers for measuring, the relative amplitudes of the various components of a television signal. Reference white is assigned a value of 100, blanking a value of 0. One IRE unit corresponds to 7 1/7 mv in CCIR System M/NTSC and to 7.0 mv in all other systems
ISO
International Organization for Standardization. The ISO and its affiliated International Electro-technical Commission (IEC) are the two major global standards-making groups
ITU
The United Nations regulatory body governing all forms of communications. ITU-R (previously CCIR) regulates the radio frequency spectrum, while ITU-T (previously CCITT) deals with the telecommunications standards
Jitter
The variation in timing and/or displacement upon transmission or arrival of digital signal. High Jitter can severely degrade the performance of an otherwise ideal system by introducing unwanted noise at the receiver
Judder
A temporal artifact associated with moving images when the image is sampled at one frame rate and converted to a different frame rate for display. As a result, motion vectors in the display may appear to represent discontinuously varying velocities
JPEG
Joint Photographic Experts Group. An international standards group functioning under ISO and IEC, developing international standards for image compression algorithms for continuous-tone still color pictures
Key channel
See Alpha channel
Keyer
A device which inserts data into the video bit stream based upon a supplied key signal. The data can be video/audio overlay, or broadcast data
KeyKode
A system of latent edge numbers developed by Eastman Kodak. A similar system known as MR Code is used by Fuji Film. These human readable and machine readable (barcode) numbers are located on the edge of motion picture film stock and are used to number film frames during post production. Tracking these KeyKode numbers accurately is essential for successful post production of film originated material
L-band
A frequency band ranging from 950MHz-2150MHz and used mainly in satellite signal transmission over fiber. Multiple sub-carriers within this spectrum carry many video channels to satellite recievers where single channels can be selected
Letterbox
Letterbox describes a video frame that the image fails to fill vertically, requiring bars without picture information at the top and/or the bottom of the image
Logo Inserter
A specific type of keyer which inserts static or animated images or "bugs" into a video bit stream overlaying the image
LTC
Linear Time Code or Longitudinal Time Code. This time and address control signal standardised by SMPTE ST 12-1 has been in widespread use in the professional video and audio industries since 1975. It is typically written on a time code or address track of a video recorder and provides an individual frame number for each video frame recorded. LTC is also commonly used to distribute time of day information to wall clocks, automation systems and other devices throughout a television facility. In regions of the world using the NTSC or similar non-integer (1/1.001) frame rates, LTC locked to the video frame rate does not maintain accurate time and must be corrected regularly when it is used convey time of day information. (See also Drop Frame and VITC)
Matrix Time Code
See AatonCode
Mux
An abbreviation of 'multiplexing' which is a method of joining of two or more data streams for co-transmission over the same hardware. When used as a noun it describes the device that does the multiplexing. This term is often used synonymously with Embedding when used to describe the process of inserting AES audio into a serial digital video signal
MVP®
The product name for Evertz premier Monitoring and Multi-Image Video Processor System
NTP
The public domain software package called NTP (Network Time Protocol) is an implementation of the TCP/IP network protocol with the same name. NTP is now widely used around the world to achieve high accuracy time synchronization for computers across a network. The protocol supports an accuracy of time down to nanoseconds however; the real accuracy that can be achieved also depends on the operating system and the network performance
NTSC
National Television Standards Committee. An analog video format with 525 lines per frame, used as the broadcast standard for United States, Canada, Japan and several other countries
OSD
On Screen Display. A system where important information such as graphs and warnings overwrite a visual display
PAL
Phase Alteration Line. An analog video format with 625 lines per frame, used as the standard for most European broadcasters, and other parts of the world outside North America and Japan
Pan-Scan
Pan-Scan information is a set of data that is intended to guide professional video equipment in extracting an image to be presented in an aspect ratio that is different from that in which the material was produced or distributed. Independent parameters are provided for pan (horizontal displacement), tilt (vertical displacement), vertical size, horizontal size and output aspect ratio. Pan-Scan information is not intended for use beyond the production and distribution environments. AFD and Bar Data are described in a forthcoming SMPTE standard
Pillarbox
Pillarbox describes a frame that the image fails to fill horizontally, requiring bars without picture information at the left and/or right sides of the image. The term "sidebar" and "pillarbar" are sometimes used to pillarbox in a 16:9 display area
Pixel
The smallest distinguishable and resolvable area in a video image. A single point on the screen. In digital video, a single sample of the picture. Derived from the words picture element
Reclocking
A method for signal regeneration and jitter reduction involving clock and data recovery
Resolution
The number of bits (four, eight, ten, etc.) determines the resolution of the signal. Eight bits is the minimum resolution for broadcast television signals.
- 4 bits = a resolution of 1 in 16
- 8 bits = a resolution of 1 in 256
- 10 bits = a resolution of 1 in 1024
RGB
The three primary colour signals: red, green, and blue (RGB) that together convey all necessary picture information. In normal high definition digital video, these three primary components are scaled such that the extreme values are code words 040h (64) and 3ACh (940) in a 10-bit representation. See also FSRGB
Router
A multi-input, multi-output device that allows for quick switching from one video input to another without recabling
RU
Rack Unit. A standard unit of measurement equivalent to 1.75 inches or 45 mm, used for audio-visual equipment racks
SAV
Abbreviation for "Start of Active Video". A digital synchronization sequence consisting of a sequence of four consecutive code words (a code word of all ones, a code word of all zeros, another code word of all zeros, and a code word including F (field/frame), V (vertical), H (horizontal), P3, P2, P1, and P0 (parity) bits.) which is used to designate the end of the horizontal blanking interval. The pixel immediately following the SAV is known as pixel 0 and designates the first pixel of the specific line of the digital image. See also EAV
Serial Digital (SDI)
Serial Digital Interface a standardised interface for transmitting digital television signals using a coaxial cable in serial form. Often used informally to refer to the 4:2:2 sampled standard definition serial digital television signals as specified in SMPTE ST 259
SDI
Serial Digital Interface. A bit-serial digital interface for SDTV component signals operating at data rates ranging from 19.4Mb/s up to 540Mb/s. The SDI interface is standardized in SMPTE ST 259, SMPTE ST 310 and can be carried over coaxial and fiber optic cables
sF
Acronym for segmented frame which is a method of transporting progressive HDTV images over an HD-SDI interface. The picture is progressively scanned, however it is divided into two segments, containing the odd and even lines. The segments are then sent out the serial digital interface in the same way that the fields of an interlaced video signal are. This format is often used at nominal frame rates of 24, 25 or 30 frames per second
SMPTE
Society of Motion Picture and Television Engineers. SMPTE is a professional organisation that recommends standards for the film and television industries. Evertz is a sustaining member of this engineering organization
SNMP
Simple Network Management Protocol. SNMP is a standard computer network protocol that enables different devices sharing the same network to communicate with each other
SoftSwitch™
The name for Evertz patent pending method of providing 'popless' audio transitions from one audio source to another
S-Video
Super-video or Component video. A format in which a video signal is split into a Luminance (brightness) component and a Chrominance (color) component
TRS
Timing reference signals used in composite digital systems. It is four words long.
TRS-ID
Abbreviation for "Timing Reference Signal Identification". A reference signal used to maintain timing in composite digital systems. It is four words long.
Telecine
A device that transfers motion picture film to video. This sometimes involves changing the frame rate by inserting a 3:2 pulldown
Time Code or Timecode
See Linear Time Code and Vertical interval Time Code
Tri-level Sync
An HDTV synchronization signal
Unbalanced Audio
A method of transmitting audio over normal video coaxial cabling with 75Ω impedance
Upconverter
A converter which takes an SDI signal and recodes it as an HD-SDI signal
User bits
32 bits in the time code are user assignable. They typically are used to contain date, reel numbers, scene and take numbers, or other user-oriented data
VANC
Vertical Ancillary Data. Acronym for ancillary data packets carried in the active part of the lines which are during the vertical blanking interval of a digital television signal. May also refer to the data space located in the vertical blanking interval where these packets are carried. Ancillary data packets contain metadata associated with the video or audio of a television bitstream. See also HANC
V-Chip
Program rating information encoded onto a broadcast video signal as an XDS packet in a Line 21 closed caption system. Television sets with V-Chip decoders will disallow viewing of programs if the rating is too high
VIP
The product name for Evertz Video-Image Processor modules. These modules take multiple video inputs and combined them into one composite display while monitoring the video and audio inputs and reporting anomalies to the operator using the VistaLINK® system
VITC
Vertical Interval Time Code. This time and address control signal standardised by SMPTE ST 12-1 is encoded on one or more lines in the vertical interval of standard definition television signals
VGA
Video Graphics Array. A computer video adapter which can display 16 colours at a resolution of 640x480 or 256 colours at 320x200
VLPRO
Abbreviation for VistaLINK® PRO The name for Evertz Monitoring and control software used to control and monitor many of our 7700 / 7800 series and 500 series modules. May also be referred to a VistaLINK® which is a registered Evertz trademark. VistaLINK® is Evertz's remote monitoring and control capability over an Ethernet network using Simple Network Management Protocol (SNMP)
Word Clock
An acknowledgement and transmission signal which enables a receiving system to adjust it's timing for incoming digital audio packets
XDS
eXtended Data Service. XDS involves a system of data packets sent with the broadcast which can deliver: program rating information such as age-appropriateness, the current time, or local weather reports
YPrPb
A compressed bandwidth RGB signal. The video luminance (Y) is transmitted only once instead of once with each RGB channel, requiring more processing power at the receiving end, but reducing transfer rates by a third