FAQs — Terminology

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Advanced Television Standards Committee. Also refers to the method of broadcasting HDTV television. ATSC Homepage


Nation Television Standards Committee. Also refers to the method of broadcasting standard television.


Standard Definition Television. 460 x 480 pixels,  interlaced scan.


Enhanced Definition Television. 460 x 480 or 720 x 480  (widescreen) pixels, interlaced or progressive scan.


High Definition Television. 1280 x 720 progressive scan or 1920 x 1080 interlaced scan.

Progressive Scan

A method of displaying images where all horizontal lines are displayed in a single pass. Digital TV can support 24, 30 or 60 fps.

Interlace Scan

A method of displaying images where the image is divided in to two fields, the 1st field is composed of the odd numbered horizontal lines and drawn first, the 2nd field composing  of the even horizontal lines is then drawn.


 460 x 480 pixels, interlaced scan at 30 fps. SDTV


720 x 480 pixels, progressive scan. EDTV at 24, 30 or 60 fps


1280 x 720 pixels, progressive scan. HDTV at 24,30 or 60 fps


1920 x 1080 pixels interlace scan. HDTV at 30 fps.


8-level Vestigial Sideband. The modulation method used in broadcasting HDTV.  8VSB article


Moving Picture Experts Group. MPEG-2 is  the standard on which such products as Digital Television set top boxes and DVD are base. MPEG homepage.

Satellite companies are starting to use MPEG-4 for their HD transmissions. This algorithm allows the broadcaster to reduce the bandwidth required to send the signal (hence giving them more space to transmit more channels) while giving the same picture quality or better than MPEG-2 transmissions.

Dolby Digital

Method for encoding sound in HDTV and DVDs. Dolby Digital offers greater dynamic range than analog audio, and has a wider frequency range (bass to treble). It also has separate left and right surrounds, a low-frequency effects channel, and a center channel in addition to the left and right front channels. Dolby Laboratories Home Page


The informal name of the SMPTE 421M video codec standard.  Both HD DVD and Blu-ray Disc have adopted VC-1 as a video standard. HD DVD and Blu-ray players will be capable of  playing discs compressed using VC-1.