1080i - 1080 interlaced; one of two formats designated as high-definition television in the
ATSC DTV standard, with 1,080 vertical
pixels by 1,920 horizontal pixels. The
i stands for
interlaced, as opposed to
progressive scanning, used in the second HDTV standard,
720p. Contrary to myth, 1080i is not superior to 720p; 1080i has more scanning lines but also suffers the disadvantages of interlaced scanning.
16:9 - Sometimes expressed as
16x9 or
16 by 9 (known as
1.78:1 in the film world); the standard DTV
wide-screen television screen size, or
aspect ratio--16 arbitrary units wide by 9 arbitrary units high, as compared to a standard TV aspect ratio of 4:3. The phrase describes the shape of a TV set or program, not an actual inch measurement.
2:3 pull-down detection - Also (and less accurately) called
3:2 pull-down; digital technology developed by Faroudja to accurately convert and display content originally on celluloid film, which runs at 24
frames per second (fps) compared to the 30fps rate of television. It is found in many DVD players and DTVs.
4:3 - Standard "square" NTSC TV screen-size
aspect ratio of 4 arbitrary units wide by 3 arbitrary units high; often expressed as
4x3 or
4 by 3. It was originally known as the Academy Ratio (as in Academy of Motion Picture Arts and Sciences, the film industry organization that awards the Oscars) prior to 1954 and the introduction of wide-screen aspect-ratio film formats; also known in the film world as
1.33:1.
480i - 480 interlaced; form of standard-definition digital television
(SDTV) that approximates the quality of analog television but not considered high-definition television (HDTV). Even though the
native resolution of DVDs is 480p, they are viewed at 480i on an NTSC analog television.
480p - 480 progressive; form of standard-definition digital television
(SDTV) comparable to VGA computer displays but not considered high-definition television (HDTV), though 480p is discernibly cleaner and slightly sharper than analog television. The native resolution of DVD is 480p, but that resolution can be seen only if a DVD player outputs a
progressive-scan signal and the DTV has progressive-scan or component-video inputs; it is also known as
EDTV.
5C DTCP - 5 company Digital Transmission Content Protection. An HDTV copy-protection encryption method for devices connected via
FireWire, this allows one of three copy states: copy always (all ATSC broadcast and "in the clear"
QAM cable broadcasts); copy once (premium cable); and, copy never (pay per view, video-on-demand). Bidirectional system requires 5C chips in every device in an A/V system (in other words, a
set-top box, a TV, and so on); the TV "requests" acknowledgment before allowing the signal to be viewed or recorded. Proposed and sponsored by Hitachi, Intel, Matsushita (Panasonic), Sony, and Toshiba--the five companies.
720p - 720 progressive. One of two currently used formats designated as high-definition television in the
ATSC DTV standard, this technology comprises 720 vertical
pixels and 1,280 horizontal pixels. The
p stands for
progressive, as opposed to interlaced, scanning, which is used in the other accepted HDTV standard, known as
1080i. Contrary to myth, 720p is not inferior to 1080i; 720p has fewer lines but also has the advantages of progressive scanning and a constant vertical resolution of 720 lines, making it better able to handle motion.
8VSB - 8 vestigial side band; DTV broadcast system developed largely by Zenith and used for DTV broadcasts in the United States.