Enhanced-definition television
From Free net encyclopedia
Enhanced-definition television, extended-definition television, or EDTV is a CEA marketing shorthand term for certain digital television (DTV) formats.
EDTV generally refers to a standard-definition 480-line signal that is broadcast at 60 progressive (complete) frames per second (as opposed to 60 interlaced fields per second, see NTSC) or to a 576-line signal that is broadcast at 50 progressive frames per second (as opposed to 50 interlaced fields per second, see PAL and SECAM). This is commonly referred to as "480p" and "576p" respectively. A standard definition television signal is broadcast with interlaced frames and is commonly referred to as "480i" or "576i".
EDTV signals are often broadcast in a 16:9 aspect ratio, and are generally considered equivalent in picture quality to the DVD format. The horizontal resolution differs from 352 to 768 pixels, but most often is 704 or 720 pixels, which has to be stretched for displaying to an aspect ratio of 4:3 or 16:9.
In the United States, the ATSC official DTV formats include SDTV, and HDTV. EDTV is considered part of the HDTV standard.
Prior to the 2004–2005 television season, the Fox Network was broadcasting in EDTV in the United States. As of the 2004–2005 season, they have begun broadcasting in 720p, an HDTV format.