Menu Picture
Frame Image
Frame Image
   Glossary

0-9    A-B    C-D    E-I    J-N    O-R    S-Z

5.1 Sound: A surround sound system which supports six discrete audio channels, namely Left, Center, Right, Rear Left, Rear Right, and Subwoofer (See also Dolby Digital).

back to top

Analogue Signal: An analogue signal has levels continuously varying with time, as opposed to a digital signal that contains discrete levels.

back to top

Analogue System: A system that operates primarily on analogue signals.

back to top

Aspect Ratio: The width to height ratio of a TV picture. For the current analogue television system (e.g., NTSC and PAL), the aspect ratio is 4:3. For widescreen video such as high definition television (HDTV), it is typically 16:9.

back to top

ATSC (Advanced Television Systems Committee): The ATSC is formed to establish technical standards for advanced television systems in the US, including digital high definition television (HDTV). The standard for digital terrestrial television developed by the ATSC, now known as the "ATSC standard", has been formally adopted in the US as the digital terrestrial television transmission standard. More information can be obtained from the ATSC web site at www.atsc.org.

back to top

Broadband TV: Television service transmitted through a broadband network. (See also IPTV)

back to top

CABD (Communal Aerial Broadcast Distribution): A system installed inside a building to receive free-to-air TV/FM signals transmitted via radio frequencies and distribute them to the audience. (See also IBCCDS and SMATV)

back to top

Cable TV: Television service transmitted through a hybrid network of optical fiber and coaxial cable.

back to top

Compression: A technique for reducing the amount of digital data by removing redundant information or non-critical data. In video and image compression, pictures are analyzed to look for redundancy and repetition, and unnecessary data are discarded in order to reduce the amount of data for transmission or storage.

back to top

Conditional Access: A technique whereby digital television signals are scrambled (or encoded) in such a way that they can only be interpreted by the corresponding special decoder. By using valid access card (such as smartcard) and special codes transmitted together with the digital television signals, the broadcaster can limit user access to the authorized channels or services only. Conditional access is widely used in subscription TV services.

back to top

Coverage Area: Coverage area for terrestrial television is the area in which the television signals transmitted from a television broadcasting station can be received with reasonable quality.

back to top

Dolby Digital (formerly Dolby AC-3): A 5.1 sound system for audio standard adopted in digital television standard. (See also 5.1 Sound)

back to top

DTS (Digital Theatre System): One of the digital multi-channel audio systems adopted for digital TV. (See also 5.1 Sound and Dolby Digital)

back to top

DTT (Digital Terrestrial Television): It refers to the broadcast of digital television services using terrestrial radio transmission.

back to top

DVB (Digital Video Broadcasting): It is a suite of standards developed by the DVB Group for digital broadcasting in Europe and other places and is categorized according to different transmission platforms as follows:

  • DVB-S - satellite platform
  • DVB-C - cable platform
  • DVB-T - terrestrial radio platform
More information can be obtained from the DVB web site at www.dvb.org.
back to top

DVB-T: See DVB.
back to top

DVD (Digital Versatile Disk): It is a high-density storage medium for digital video programmes. It has the same dimension as a compact disk (CD). A single sided, single layer disk DVD stores data some seven times of a typical CD capacity.

back to top

DVI (Digital Visual Interface): It is a video connector interface designed to maximize the visual quality of digital display devices such as flat panel LCD displays. It is developed by an industry consortium, the Digital Display Working Group (DDWG). (See also HDMI, TV Connectivity and YPbPr)

back to top

Encryption: It refers to the process of encoding data for information protection. Original data could only be restored from the encrypted data through a special decoding process with the use of a specific data code, commonly referred to as the key. (See also Conditional Access)

back to top

EPG (Electronic Programme Guide): An application that provides on-screen listing and navigation of programme services to assist a user of digital television or interactive television services to identify and select the intended programme service for viewing and/or recording.

back to top

HDMI (High Definition Multimedia Interface): It is an industry-supported, uncompressed, all-digital audio/video interface. HDMI provides an interface between any compatible digital audio/video source, such as a set-top box, DVD player, and audio/video receiver, and a compatible digital audio and/or video display, such as a digital television set. HDMI supports standard, enhanced, or high-definition video, plus multi-channel digital audio on a single cable. (See also DVI, TV Connectivity and YPbPr)

back to top

HDTV (High Definition Television): A television system which provides up to five times the resolution of standard definition television (SDTV) and supports a typical widescreen aspect ratio of 16:9. There are various options on the number of lines and pixels such as 1280 x 720 and 1920 x 1080, etc. (See also SDTV and Widescreen)

back to top

IBCCDS (In-Building Coaxial Cable Distribution System): A coaxial cable system installed inside a building for distributing and relaying signals for telecommunications, broadcasting and security services. It may include CABD system, SMATV system, closed circuit TV (CCTV) system, cable TV system or any combination of these. (See also CABD and SMATV)

back to top

iDTV (Integrated Digital Television): A TV set which has the digital decoder already built in or "integrated".

back to top

Interactive Television: A combination of television with interactive content and enhancements. Interactive television provides better, richer entertainment and information, blending traditional TV-watching with the interactivity of a personal computer. Programming can include richer graphics, one-click access to web sites, electronic mail and chats, and online commerce through a return channel.

back to top

Interlaced Scanning: Interlaced scanning in TV system divides a picture into frames for the odd- and even-numbered lines and the frames are transmitted alternatively to the receiving end. Pictures are re-constructed for display on the TV screen one frame at a time. Due to the slow response of a human eye, viewers will not be able to see such incomplete picture frames but will perceive one complete picture instead. Interlaced scanning reduces the data rate of broadcast transmission. (See also Progressive Scanning)

back to top

IPTV (Internet Protocol Television): Digital television service transmitted through a broadband network using the Internet Protocol (IP)

back to top

ISDB-T (Integrated Services Digital Broadcasting - Terrestrial): It is Japan's national transmission standard for digital terrestrial television broadcasting. More information can be obtained from the web site of the Digital Broadcasting Experts Group (DiBEG) at www.dibeg.org.

back to top

MFN (Multiple Frequency Network): A network of independent broadcasting transmitters which operate on more than one radio frequency to cover an intended area. All transmitters of an MFN carry the same television programme signals. (See also SFN)

back to top

MPEG: Compression standards for moving images developed by the Motion Pictures Expert Group which is an international group of industry experts set up to standardize compressed moving pictures and audio. MPEG-1, MPEG-2 and MPEG-4 are popular MPEG standards for digital video applications.

  • MPEG-1 is used specifically for VCD and CD-i media, but the quality is not good enough for TV broadcast.
  • MPEG-2 is widely used for digital TV broadcast and DVD.
  • MPEG-4 is an advanced coding and compression standard which is a successor to MPEG-2.

The latest video coding part of the standard, MPEG-4 Part 10 which is also known as MPEG-4 AVC or H.264, is capable of supporting transmission of digital video signal with broadcast TV (PAL) quality at half the data rate of MPEG-2 or even less.
back to top

(DTT) Multiplex: A digital transmission channel which is capable of carrying more than one programme service and other additional data services.

back to top

National Standard: It refers to the national standard of digital terrestrial television (DTT) announced by the Standardization Administration of China (SAC) in August 2006 which is named "GB 20600-2006: Framing Structure, Channel Coding and Modulation for Digital Television Terrestrial Broadcasting System". This standard will be officially implemented on 1 August 2007. Broadcasters in the Mainland who are offering DTT services based on other transmission standards must switch to the national standard by this deadline.

back to top

NTSC (National Television System Committee): which developed the analogue television broadcast standard currently in use in the US, Canada, and Japan. The term now also refers to the corresponding TV standard which defines a maximum of 525 lines (487 active lines) for a TV picture. (See also PAL and SECAM)

back to top

PAL (Phase Alternate Line): It is the analogue television broadcast standard adopted throughout Europe (except in France and Eastern Europe where SECAM is the standard) and in many Asian countries. In particular, Hong Kong uses the PAL-I system while the Mainland uses the PAL-D system. The PAL standard defines a maximum of 625 lines (576 active lines) for a TV picture. (See also NTSC and SECAM)

back to top

Pixel: Pixel refers to one sample of picture information which is a short form for "Picture Cell" or "Picture Element."

back to top

Progressive Scanning: A video scanning system where lines of a picture are transmitted consecutively. It is an alternative scanning system to the interlaced scanning. For the same number of scanning lines, progressive scanning enables the reconstruction of picture with better quality than the interlaced scanning at the expense of higher data rate. (See also Interlaced Scanning)

back to top

Resolution: A measure of the finest detail that can be seen, or resolved, in a reproduced picture.

back to top

Satellite TV: TV service transmitted through satellite communications.

back to top

SECAM: Sequential Couleur Avec Mémoire. It is the analogue television broadcast standard adopted in France, the Middle East, and most of Eastern Europe. SECAM defines a maximum of 625 lines for a TV picture. (See also NTSC and PAL)

back to top

SDTV (Standard Definition Television): SDTV can be considered as the digitized version of the conventional TV system, both of which have the same screen format and picture resolution. However, SDTV pictures are free from 'ghosting' and 'snowing', which are commonly found on analogue broadcasts. (See also HDTV and Widescreen)

back to top

SFN (Single Frequency Network): A network of synchronized broadcasting transmitters which carry the same television programme signals and operate on the same frequency to cover an intended area. (See also MFN)

back to top

Simulcast: To broadcast the same programme over two different transmission systems is called simulcast. In the process of migration from analogue to digital TV broadcast, many countries require that television operators should simulcast their digital and analogue television signals until analogue TV is completely switched off. This is necessary to ensure a gradual, smooth transition from analogue to digital broadcasting.

back to top

SMATV (Satellite Master Antenna TV): A system installed in multi-storey buildings to receive satellite TV signals and distribute them to the audience. (See also CABD and IBCCDS)

back to top

STB (Set-top Box): An STB for digital TV broadcasts is a receiver (named because it typically sits on top of a television set) to decode and convert digital TV signals for display on a TV set.

back to top

TV Connectivity: TV Connectivity: A set of inputs and outputs used to hook up a TV set to other equipment. Typical connectivity is as follows. (Also see DVI, HDMI and YPbPr)

Jack Cable Connector Connection Type Typical use Support for
HDTV
jac 1 jac 2 Antenna Plug
Antenna Plug, also knows as radio frequency (RF) connector, is commonly used to deliver terrestrial TV signals. The cable carries both video and audio signals and more than one TV signals in general. Two common types of aerial plug are IEC169-2 connector and F connector.
Antennae, TV sets, VCRs, DVD recorders, set-top boxes for terrestrial, cable or satellite TV, FM radio, etc. Yes - depending on the functionality of the equipment
jac 3 jac 4 Composite Video
Composite connectors, also known as A/V cables, use one single cable (yellow) to carry video signals and two cables (red and white) to convey stereophonic audio signals.
TV sets, set-top boxes, VCRs, DVD players/recorders, game consoles, etc. No
jac 5 jac 6 S-Video
Separate Video, abbreviated as S-Video, is an analogue video signal which carries brightness and colour data as separate signals. It is usually given in a 4-pin plug and offers signal quality better than that of composite video.
Set-top boxes, TV sets, Super VHS VCRs, DVD players/ recorders, game consoles, etc. No
jac 7 jac 8 Component Video
Component Video separates the analogue video information into two or more signals. A common type of implementation consists of a luminance channel (Y) and two colour channels (Pb & Pr).
DVD players, TV sets, HDTV sets, set-top boxes, etc. Yes - depending on the functionality of the equipment
jac 9 jac 10 RGB
In RGB model, red, green and blue are combined to generate other colours. These three colours are carried in separate pins of the RGB cables. Common types of implementation include VGA connector (15-pin Mini D-sub) and RGB-HV.
Personal computers, set-top boxes, video processors and projectors, etc. Yes - in general
jac 11 jac 12 Firewire
Firewire (also know as IEEE 1394 or i.Link) is a high-speed digital interface which is commonly used to transmit data between personal computers and audio-visual devices.
Personal computers, camcorders, DVD recorders, etc. Yes - depending on the functionality of the equipment
jac 13 jac 14 DVI
DVI stands for Digital Visual Interface and is commonly used for transmitting digital video information from personal computers to LCD displays. Some HDTV receivers also use DVI for connection to displays. DVI connectors may also incorporate connection for passing analogue video signals. There are two common types of DVI connectors i.e., DVI-D for carrying digital signals only and DVI-I for carrying carry both analogue and digital signals.
Mainly found in personal computers, also available in some digital set-top boxes, HDTV sets, DVD players, etc. Yes - in general
jac 15 jac 16 HDMI
HDMI stands for High Definition Multimedia Interface. It provides connectivity between compatible digital audio / video source and receivers.
Digital set-top boxes, HDTV sets, DVD players, personal computers, etc. Yes - in general

back to top

Widescreen: The term given to picture displays that have a wider aspect ratio (usually 16:9) than the normal 4:3 aspect ratio. In addition to HDTV, widescreen is also used by some standard definition systems. (See also HDTV and SDTV)

back to top

YPbPr: A connector interface for analogue video where a video signal is separated into components of luminance and chrominance signals. Some set-top boxes have YPbPr output terminal, which transmits decoded digital TV signals to compatible analogue TV sets for display (See also DVI, HDMI and TV Connectivity).

back to top
Frame Image
Frame Image