HDTV Lingo

Active Lines - Scanning formats are measured in active lines of picture elements of pixels transmitted, both horizontal and vertical. The number of total pixels is calculated by multiplying the amount of vertical lines by the density of horizontal picture elements. For example, the 1920x1080 HDTV format has more than 2 million pixels. (1920 X 1080 = 2,073,600) today's NTSC video only has a resolution of 211,200 pixels (480 vertical lines and 440 horizontal pixels).

Aspect Ratio - The aspect ratio refers to the shape of the video image. Today's television has a 4:3 aspect ratio, which is almost square in appearance. Digital television will have either a 4:3 or 16:9 aspect ratio. A 16:9 aspect ratio is widescreen, and appears rectangular; this looks more like a movie screen, filling more of the viewer's field of vision for a more lifelike viewing experience.

Datacasting - Links information for various sources, such as the Internet, to the television broadcast and allows the information to be displayed on-screen at the same time as a television program or delivered to your PC. You will then be able to get the latest stock quotes, access statistics on your favorite player during a football game, or order the product you just saw advertised right from your TV.

DTV Formats - The most common high-definition formats are 1080i (1,080 interlaced scan lines) and 720p (720 progressive scan lines). The most common standard-definition formats are 480i (480 interlaced scan lines) and 480p (480 progressive scan lines.

Enhanced Definition Television (EDTV) - EDTV refers to a complete product/system with the following minimum performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes alll ATSC Table 3 video formats
- Display Scanning Format: Has active vertical scanning lines of 480 progressive (480p) or higher
- Aspect Ratio: None Specified
- Audio: Receives and reproduces, and/or outputs Dolby Digital audio

Enhanced Definition Television (EDTV) Monitor - EDTV Monitor refers to a monitor or display with the following minimum performance attributes:
- Display Scanning Format: Has active vertical scanning lines of 480 progressive (480p) or higher
- Aspect Ratio: None specified

Enhanced Definition Television (EDTV) Tuner - EDTV Tuner refers to a RF receiver with the following minimum performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats
- Outputs: Outputs the ATSC Table 3 720p and 1080i/p and 480p formats with minimum active vertical scanning lines of 480p. Alternatively, the output can be a digital bitstream output capable of transporting 480p, except the ATSC Table 3 480i format can be output at 480i.
- Audio: Receives and reproduces, and/or outputs Dolby Digital audio.

Frame Rate - Frame rate, also known as picture rate, is the speed at which the lines are scanned in order to create a video frame, 60-, 30-, or 24-frames per second.

HD-Ready - A TV set that can display full resolution widescreen high-definition images when connected to an outboard digital TV tuner/decoder.

High-Definition Television (HDTV) - A specific subset of the digital TV standard that features increased horizontal and vertical resolution, interlaced or progressive scanning, and widescreen images. HDTV refers to a complete product/system with the following minimum performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats
- Display Scanning Format: Has active vertical scanning lines of 720 progressive (720p), 1080 interlace (1080i), or higher
- Aspect Ratio: Capable of displaying a 16:9 image (1).
- Audio: Receives and reproduces, and/or outputs Dolby digital audio.

High-Definition Television (HDTV) Monitor - HDTV Monitor refers to a monitor or display with the following minimum performance attributes:
- Display Scanning Format: Has active vertical scanning lines of 720 progressive (720p), 1080 Interlaced (1080i) or higher
- Aspect Ratio: Capable of displaying a 16:9 image (1)

(1) In specifications found on product literature and in owner's manuals, manufacturers are required to disclose the number of vertical scanning lines in the 16:9 viewable area, which must be 540p, 810i or higher to meet the definition of HDTV.

High Definition Television (HDTV) Tuner - HDTV Tuner refers to a RF receiver with the following minimum performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats
- Outputs: Outputs the ATSC Table 3 720p and 1080i/p formats in the form of HD with minimum active vertical scanning lines of 720p, 1080i, or higher. Additionally, it may output HD formats converted to other formats. The lower the resolution ATSC Table 3 formats can be output at lower resolution levels. Alternatively, the output can be a digital bitstream with the full resolution of the broadcast signal.
- Audio: Receives and reproduces, and/or outputs Dolby Digital audio.

IEEE 1394 - The Institute of Electrical and Electronics Engineers (IEEE) standard of high-speed, high-capacity digital connections of audio and video components, computers, and peripherals; also known as Firewire and i.Link.

Interlaced Scanning - A video component or signal that assigns alternating scan lines in a video frame to one of two fields, which are then displayed separately (the opposite of progressive scanning). Abbreviated as "i" in DTV format names.

Multicasting - Allows a broadcaster to transmit several standard-definition digital programs at the same time. For example, a broadcaster may show a high-definition movie, a popular sitcom and a news program all at the same time.

Progressive Scanning - A video component or signal that processes or displays each scan line of a video frame in sequence. Abbreviated as "p" in DTV format names.

Scanning Method - Frames of video are made up of many lines of video that are scanned onto a television screen so closely they appear to be a solid picture. The scanning method can be either interlaced or progressive. Interlaced scanning (also used in today's analog TV), indicated by an "i" in the video format, fills in the odd number lines (1,3,5,7...) and then fills in the even number lines (2,4,6,8...) until the frame is complete. Progressive scanning, "p" fills in each line consecutively until the frame is complete, like a computer display.

SD-Ready - A TV set that can display a 480p-format standard-definition digital TV signal, if connected to an outboard tuner/decoder, as well as VGA and SVGA signals from a computer.

Set-Top Box - any of several types of decoder, such as for cable TV, digital TV, or Internet functions, designed for hookup to a TV set.

Standard-Definition Television (SDTV) - A subset of the digital TV (DTV) standard that includes DTV signals with picture quality at least as good as that of conventional analog television. SDTV refers to a complete product/system with the following performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats, and produces a useable picture.
- Display Scanning Format: has active vertical scanning lines less than that of EDTV.
- Aspect Ratio: None specified
- Audio: Receives and reproduces usable audio.

Standard Definition Television (SDTV) Tuner - SDTV Tuner refers to a RF receiver with the following minimum performance attributes:
- Receiver: Receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats.
- Outputs: Outputs all ATSC table 3 formats in the form of NTSC output.
- Audio: Receives and reproduces, and/or outputs Dolby Digital audio.

Widescreen - Program material of a component that contains or operates with images of wider than "normal" aspect ratio ( which is 4:3). HDTV's widescreen aspect ratio if 16:9.