Enhanced-definition television, extended-definition
television, or EDTV is a CEA marketing shorthand term for
certain digital television (DTV) formats.
EDTV generally refers to video with picture quality beyond
what is broadcastable in NTSC or PAL, but not sharp enough
to be considered High-definition television (HDTV). A DVD
player with progressive output is considered the lower end
of this class, when playing a progressively encoded disc.
(The maximum EDTV frame rate of 60p is not possible from a
DVD.) The common implementations of EDTV are 480 or 576-line
signals in progressive scan (as opposed to 50-60 interlaced
fields per second, see NTSC, or PAL and SECAM). These are
commonly referred to as "480p" and "576p"
respectively. In comparison, a standard definition television
(SDTV) signal is broadcast with interlaced frames and is commonly
referred to as "480i" or "576i".
Because EDTV signals use a progressive scan, they have about
50% more vertical resolution than interlaced SDTV pictures
with the same number of lines, and do not show the spatial/temporal
aliasing artifacts associated with interlaced video. As a
result, EDTV material gives much better results when upconverted
for display on HDTV television sets. However, because of the
higher level of spatial coherence within single progressive
frames as compared to single interlaced fields, EDTV does
not increase the amount of data bandwidth proportionately
to the greater number of pixels displayed per second.
The use of EDTV instead of HDTV allows DTV stations to broadcast
multiple programs at once while still improving quality over
standard broadcasts.
EDTV signals are often broadcast in a 16:9 aspect ratio,
with non-square pixels. The horizontal resolution is 704 or
720 pixels regardless of aspect ratio. The image is stretched
for displaying to an aspect ratio of 4:3 or 16:9.
EDTV signals are often broadcast in a 16:9 aspect ratio,
with non-square pixels. The horizontal resolution is 704 or
720 pixels regardless of aspect ratio. The image is stretched
for displaying to an aspect ratio of 4:3 or 16:9.
Prior to the 2004–2005 television season, FOX was broadcasting
in EDTV in the United States. As of the 2004–2005 season,
they have begun broadcasting in 720p, an HDTV format.
Nintendo's latest video game console, Wii, produces 480p
signal, which is EDTV.

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