Analog—Commonly refers to the current NTSC transmission standard for televisions.
Aspect Ratio—The ratio of the width to the height of a TV screen independent of the screen size (x units wide by x units high). Analog is 4:3; Digital can be 4:3 or 16:9 (also called wide screen).
ATSC—Advanced Television Systems Committee
AV Jacks—Audio Video Jacks
Bandwidth—The range of frequencies assigned to a broadcast channel. A TV channel is 6 MHz wide.
Component Jacks (Y Pb Pr)—Green, Blue, and Red video jacks that accept 480i, 480p, 720p, and 1080i signals. By separating the Green (Y), Blue (Pb), and Red (Pr) video signal components, clearer, more-defined images that exceed the performance of S-Video and Composite video jacks are achieved.
Composite Jacks—White, Red, and Yellow AV jacks. The White and Red jacks carry the Left and Right audio signals while the Yellow jack carries the composite video signal.
Dolby® Digital (Formally known as Dolby AC-3)—A 5.1 channel (Front L/R, Rear L/R, Center, and Bass) surround sound audio standard for digital television.
Downconverting—The removal of pixels. Frame rate and/or scanning format may also change. Broadcasters may use this process to make room in their bandwidth for additional services, such as, sub-channels.
DTV (Digital Television)—Comprises four elements, HDTV, EDTV, SDTV, and Multicasting.
DVI—Digital Visual Interface. A pure digital video interface that can pass standard-definition and high-definition video signals. It supports the HDCP copy protection standard, allowing transmission of copy-protected digital content.
EDTV—Enhanced-Definition TV (480p)
HDMI—High-Definition Multimedia Interface. An all digital audio/video interface that accepts uncompressed video signals for the very best picture possible. It supports the HDCP copy protection standard, allowing transmission of copy-protected digital content. The signal can also include Dolby® Digital or PCM audio, when available.
HDTV—High-Definition TV (720p, 1080i, & 1080p)
Input / Output Jacks—Used to receive (input) and send (output) signals from one device to another. Such as, from a DVD player (Output) to the TV (Input).
Interlaced Scanning—The process of scanning two fields of video then combining (interlacing) them to make one frame of video (or one complete image).
Letter Box—This term is used to describe a 16:9 ratio image being displayed on a 4:3 ratio display device. Black bands appear at the top and bottom of the screen.
MPEG2—A compression scheme for moving images and audio. It was developed by the Motion Picture Experts Group. This makes HDTV and multicasting possible.
Multicasting—The dividing of a station’s broadcast signal into subchannels of programming or data services. The resolution of the main channel must be reduced to make room for sub-channels.
NTSC—National Television Systems Committee
Pillar Boxing—This term is used to describe a 4:3 ratio image being displayed on a 16:9 ratio display device. Black bars (or pillars) appear at the sides of the screen.
Pixel—Picture Element
Progressive Scanning—The process of scanning lines sequentially. One scan produces one frame of video (or one complete image).
Set-Top Box (STB)—A device that receives and converts signals for display on a television screen (can be digital or analog). Many digital STBs have cable and over-the-air tuners.
SDTV—Standard-Definition TV (480i)
Signal—The picture, sound, and data transmitted or received through the air to an antenna, over a Cable TV system, from a Satellite to a dish and receiver, or between external components of an Audio/Video system.
Simulcast—Simultaneously broadcasting the same program on two or more channels. This is required by the FCC during the transition from analog to digital. Simulcasting is scheduled to end and only digital broadcasts will continue after February 17, 2009.
S-VideoJack—A round 4-pin jack that accepts separated luminance and chroma signals from a DVD player, Super VHS VCR, or similar analog device. The resolution of this input exceeds that of a composite video input (yellow connector), but is lesser than the resolution of component inputs (Y Pb Pr).
Terrestrial—An over-the-air broadcast to an antenna.
Upconverting—A process of converting original analog programming to digital for DTV broadcasting. Pixels may be duplicated and inserted between existing pixels to simulate HDTV. This does not increase the resolution. The resolution of an image is set during the recording process. It cannot be increased through conversion processes.
Wide Screen—Used to describe a 16:9 or greater aspect ratio. 16:9 is the standard aspect ratio for HDTV digital displays. Movies screens are often slightly wider.
