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T Channels

A series of standardized data channels, originally devised to carry digital voice. Includes the Tl, T2, and T3 channels.

Tl Channel

In North America, a digital transmission channel carrying data at a rate of 1.544 million bits per second. In Europe, a digital transmission channel carrying data at a rate of 2.048 million bits per second. AT&T term for a digital carrier facility used to transmit a DS-1 formatted digital signal at 1.544 Mbps.

T2 Channel

In North America, a digital channel which communicates at 5.312 Mbps. Usually for military use.


see Tape to Tape

T3 Channel

In North America, a digital channel which communicates at 45.304 Mbps. Commonly referred to by its service designation of DS-3.

Table 3 Compression Format Constraints

See: ATSC.


Telecine Analysis Film. A test film for calibrating telecine masking and level controls. Commonly used to establish Base mems


A short piece of material, audio and/or video, that is added to the end of program material.  Tags are frequently used to make local a national commercial.  (Example of a tag -- video would be a slide or still store that would say probably the same as the audio tag.  And the audio:  "Get your Goodyear tires at O'Kelly's Goodyear, 1234 Easy Street in downtown San Maybe."

Computers: A tag is a type of instruction used in HTML that browsers interpret when viewing a Web page. A pair of brackets generally surrounds tags (<>).


Term for the operational function that results in the immediate start and routing of an event to the On Air or transmission path.  In film or a video tapped production, when a particular scene is repeated and photographed more than once in an effort to get a perfect recording of some special action, each photographic record of the scene or of a repetition of the scene is known as a "take." For example, the seventh scene of a particular sequence might be photographed three times, and the resulting records would be called: Scene 7, Take l; Scene 7, Take 2; and Scene 7, Take 3.


Term for the operational function that will immediately take the next event in the playlist or sequence.


An automatic process that detects (via heartbeats) when the main system has failed and shifts to the backup system.


Control signal used to indicate the device that is currently the On Air source.  Used for operator reference and internal device control preventing the device from performing undesired operations while its output is routed to the On Air or transmission path.  

Tape Preparation 

The process a tape goes through before it is played by the automation system.       Tape preparation typically consists of recording black before and after the program material, laying down timecode and user bits and storing information about the material in the database.

 Tape to Tape

Also known as T2T. 1.A transfer from a video tape format to another, possibly different videotape format.  2. A color grading session from a video tape format to another, possibly different videotape format. Probably using a da Vinci color enhancement system.


A file compression format generally found on UNIX platforms.


Time Base Corrector. An electronic device with memory and clocking circuits to correct video signal timing errors which affect image stability and color. Required when editing from multiple video tape sources.

TCO  (Transmission Control Operator)

The individual who will use the Transmission GUIs to transmit material.

TCP/IP  (Transmission Control Protocol/Internet Protocol)

Transmission control protocol/Internet protocol. TCP/IP is a combined set of protocols that perform the transfers of data between two computers. TCP monitors and ensures correct transfer of data. IP receives the data from TCP, breaks it up into packets, and sends it to a network within the Internet. Every computer on the Internet supports TCP/IP.

TCS  (Traffic and Control System)

System designed by SunUp Digital Systems, Inc. that provides many of the functions for control and management of a television broadcast facility.  See SunUp.


Telecine Decision List. A list of the edits made in a telecine session which can be loaded into an off-line editor.

TDM  (Time division multiplex)

The management of multiple signals on one channel by alternately sending portions of each signal and assigning each portion to particular blocks of time.

TDT  (Time and Date Table)


A lateral displacement of the video lines due to sync instability. Visually it appears as though parts of the images have been torn away.


A very focused (usually) same-day promo. It is a combination invitation or an enticement to a viewer to watch a specific program or show. It can be either audio, video or both.   (an example of an audio tease:  "Stay tuned for Saturday Night Live after your local news."  Here's an example of an audio tease that would be accompanied by appropriate video clips:  "Stay tuned for the Late Show staring David Letterman.  Dave's guests tonight will be former president George Washington, and Felix the talking cat. That's tonight, right after your local news”.


l. The use of electronic telecommunication systems by groups of three or more people, at two or more locations, for the purpose of conferring with one another (source: Dr. Martin Elton, NYU). 2. Two-way communication between two or more groups, or three or more individuals, remote from each other using a telecommunications medium (Source: University of Wisconsin Extension). 3. Interactive group communication through an electronic medium (Source: Dr. Robert Johansen, Institute for the Future). Common methods of real-time teleconferencing include videoconferencing, audio conferencing, audiographic conferencing, and business television.


 Trade name for an electro-mechanical method of sending messages.  Teletype is a one kind of wire service.


A device that transfers film to video. The film could be motion or slide, but in all cases it is projected material.  The pick up device then converts the visual information into an electronic signal.  Telecines were the main stay of television broadcasting in the early days before there were video tape recorders; early television was broadcast from film via a telecine.  Telecine islands with optical switching devices, called optical multiplexers, would accommodate several projectors into one telecine camera.  Some telecine devices used a light source, some used a pulsed light and yet some were designed to pickup through the film using a scanning device as the light source.  The latter is called flying spot scan.


A text-based Internet program used for connecting to a remote host or server.

Temporal Aliasing

A defect in a video picture that occurs when the image being sampled moves too fast for the sampling rate. A common example occurs when the rapidly rotating spokes of a wagon's wheels appear to rotate backwards because of video scanning that moves more slowly than the spokes.

Temporal Resolution

The ability of the display to reproduce adequate detail to allow the visual system to distinguish the separate parts or components of an object that is moving through the display.


One trillion bytes.


A circuit or transmission line that has a terminator on one end of it.


Typically a 75 ohm load for video or 50 ohms for RF.  It is located at the end of a video coaxial cable or internally applied in a video device such as a monitor or tape deck. A restive load added to the end of a transmission path

Terrestrial Network

A teleconferencing network connected by land lines rather than satellite. Terrestrial networks are generally preferred when available—all other things being equal—because they offer shorter signal transmission delays than satellite networks.


Tornado Embedded Software. The 2K equivalent of “rtc”. The means by which the 2K interface applies hardware processing.


As applied to a negative, having low density, usually as a result of underexposure. The image from a thin negative will be very dark, with little or no shadow detail. Stretching the contrast will enhance film grain.

Tilde (or ~)

The tilde (~) signifies an individual user's Web site when housed on a server. For example, http://www.cuteftp.com/~user - says that user is a cuteftp.com user and that his homepage is on cuteftp.com's server. The tilde character is on the top line of your keyboard to the far left.


To point the camera up and down in a vertical motion.

Time Base Corrector (TBC)

A device which digitally processes the video signal in order to regenerate a time base stable sync that is in phase with the system.

A device or circuit designed to eliminate the time-base errors introduced during video recording and designed to re-establish the sync-to-subcarrier relationship.  A TBC is similar to a frame synchronizer and is often used in A/B Roll editing to genlock 2 video sources and correct time base errors upstream from a switcher.


Errors that enter into the video recording process due to the mechanical handling of the tape medium. Any slight speed change or tape stretch will ultimately mar the timely delivery of each line of information. These are corrected with devices known as Time-Base Correctors.

Time Code

1. The time, measured in hours, minutes, seconds and frames, which is recorded on a tape along with program material and user bit information. The timecode is used to locate particular points on a tape. 2. A method of identifying video frames on a recorded format.  A time code number is a series of 8 digits (SMPTE time code) which represents the hour, minute, second, and frame number of video.  Two popular systems are Longitudinal Time Code (LTC) and Vertical Interval Time Code (VITC).  

Timecode Reader Board

A board installed in the Device Server that provides input for reference     timecode, for system synchronization.

Time and Date Table

The UTC time and date, giving frequently updated information relating to the present time and date.

Time Lapse

A video tape recorder with the ability to compress real time recordings onto one tape using time lapse recording mode. On some VCRs, up to 720 or more hours can be stored on one standard tape. The Time Lapse Video Recorder records at fewer than the standard 30 frames per second of a standard VCR. By using a time lapse mode rather than real time recording, tape consumption can be dramatically reduced. For example, a 2-hour tape at normal play will last 15 hours at 4 frames per second and 20 days at 1 frame every 8 seconds!

Time Stamp

A term that indicates the time of a specific action such as the arrival of a byte or the presentation of a presentation unit.

Time-Shifted Scheduling

In NVOD, describes restarting the same event at some preset interval.


In nonlinear editing, the area in which audio and video clips are applied, typically giving duration in frames and seconds. Also seen in animation and composition software.


To bring together two events with frame-accuracy

Timing Jitter

The variation in position of a signal’s transitions occurring at a rate greater than a specified frequency, typically 10 Hz or less.  


The name given to a cassette, program, spot or segment.


Time and Logic Controller. The worlds most comprehensive telecine edit system. Originally a stand alone device TLC is integrated into DUI and TLC-2K is integrated into the 2K.

TOT  (Time Offset Table)

TOV  (Threshold of Visibility)


The source of schedules for conversion into Playlists and the final destination of As-Run logs. The functions of the traffic department can be automated by a traffic system, such as Enterprise, JIDS, and BIAS. Control of commercial production requirements for broadcast advertising.

Traffic Management System  (TMS)

A system that generates on-air schedules of events to be played backed for terrestrial or satellite broadcast and manages commercial and program contract accounts.

The broadcast station system that generates daily schedules and is usually linked to the station business system. This handles air time sales, contract management, and accounts in order to provide program/commercial scheduling information.

Traffic System

System used for scheduling a broadcast station’s air time. This system generally controls the sales/contract management and billing of air time, stores program formats, and provides management for the placement of commercials and promotional materials within the scheduled on-air programs.


This is a film term used to describe a film clip that promotes a movie.


A device which is capable of both sending and receiving information. In videoconferencing, this usually refers specifically to a device used for captured frame videoconferencing which converts video information into either audio information for transmission over a telephone line, or digital information for transmission over a digital circuit, and back again upon receipt of the signal. The DIH-2000 is a still image transceiver. Imager transceivers are used to send higher-quality, still-frame images or graphics between sites than are commonly sent through the compressed codec signal.


A device or circuit used to convert one component video format into another.  One typical transcoder is an RGB-to-Component converter that outputs Y, R-Y, B-Y from an RGB input.


Converts one type of energy (electrical or mechanical) into another.


With respect to video, it is the way once piece of video material crosses to another.  The transition can be a dissolve, fade to black, dip to black or some kind of special effect like a wipe  or pattern.

Transition Time

The time between the beginning and the end of an edit transition. While cuts are instantaneous, dissolves and other effects take time to complete. Transition time is usually displayed in tenths of seconds and may be set by tenths of seconds units from 0 to 9.9 seconds. Pressing the set keys on the edit controller increases the transition time by one unit at a time; pressing shift and set decreases the transition time one unit at a time.


A device that receives a signal on one frequency and rebroadcasts it on another. Translators are usually used to extend the range of a primary broadcast facility. They are used in both FM and Television. In the case of digital television, good translators will reprocess the digital information to ensure a minimum of bitrate errors.


Process of transmitting television signals by terrestrial or extra-terrestrial methods.  

Transmission List     

When a playlist is loaded into a transmission window, the list is referred to as a   transmission list. This is the list that is used for transmission activities.


Any device that emits radio frequency energy. Normally a transmitter will have intelligence embedded in its RF. The embedding process is normally AM, FM or digital, but can be other types of modulation.


A node on a satellite with a fixed bandwidth and uplink and downlink capabilities.

A device on a satellite that receives an uplinked signal from the earth, amplifies it, converts it to a different frequency, and returns it to earth.

Transport Stream  (TS)

A data structure defined in ISO/IEC 13818-1.

Transport Stream Header  (TS Header)

The first 4 bytes of each TS packet containing the data (PID) required for the demultiplexer in addition to the sync byte (0x47).  These bytes are not encoded.

Transport Stream ID

A unique identifier of a transport stream within a network.

Transport Stream Packet Header

The leading fields in a transport stream packet up to and including the continuity_counter field.

Triggered Event

A schedule event whose start time is determined by an external trigger such as a GPI or manual switch.

Trigger Logic

The mechanism that triggers an event in a playlist. Can be EX (tone trigger), TG (manual), TM (timed), or SQ (sequential).


Cyradis Transmission Routing System.  See also CTG-1000.


Removal of the lower significant bits on a digital word-as could be necessary when sending a 16-bit word on an 8-bit bus. If not carefully handled it can lead to unpleasant artifacts on video signals.
See also: Dynamic Rounding.

TTL  (Transistor to Transistor Logic)

Similar to GPI (see definition). A special two-level signal which can trigger external devices (e.g. character generator, frame store, or digital effects generator) to execute a command during an edit. Some external devices do not have the ability to be directly controlled by an editor. In this case, GPI or TTL pulses are used as a means of telling these devices when to execute a command. The choice of the command itself, however, must be set up on the external device and cannot be controlled by an editor.


A really bad show


A channel which is downlinked from another system. For example, HBO does not originate from MEASAT. MEASAT turns it around which means they downlink HBO from the HBO satellite and then digitize and compress it to conform it to the MEASAT signal format which can then be uplinked to the MEASAT satellite.


Generally used to refer to a fully-integrated system installed and ready for use; implies all phases of creating such systems, as well as all necessary communication links to use them.

TV Crossover Links:

A type of enhancement which notifies users that there is enhanced or Web content associated with a program or an advertisement. A TV Crossover Link appears as a small icon in the corner of the TV screen at a point in time determined by content producers. Clicking the link displays a panel, giving the viewer an option to go to the content enhancement (Web site) or continue watching TV. If the viewer chooses to go to the Web site, the receiver connects to the site, while the current program or advertisement remains on-screen. Pressing the View button on the remote control or keyboard returns to TV viewing. The term is a trademark of the Microsoft Corporation.


High-frequency audio speaker.

Twisted Pair

An electrical conductor that consists of two wires twisted around each other sometimes used in CCTV for video transmission. In twisted-pair transmission, the TV signal is compressed and converted (modulated) for transmission over inexpensive unshielded two-conductor cable. At the receiving site, it’s converted back to a conventional video signal (demodulated) for monitoring in the control center. Twisted-Pair transmission has excellent noise rejection properties and is, therefore, well suited for applications with strong RFI interference such as industrial sites, machine tools, and other sources of electromagnetic interference. However, it does sacrifice video resolution to gain these benefits.

Two-Way Audio, One-Way Video

Often used to describe business television via satellite.   Used in Instructional Television Fixed Service (ITSF)

Type C

A broadcast video format using a helical approach with the 1-inch width tape wrapping the drum almost the full 360 degrees.

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