Understanding TV Definitions

Document created by shaw-alex on Jan 15, 2013Last modified by shaw-alex on Oct 18, 2016
Version 29Show Document
  • View in full screen mode

You may hear a lot of jargon when talking about television picture. This article will help you understand what the different terms mean.


On This Page

Standard Definition (SD) vs High Definition (HD)

Interlaced vs. Progressive Scan

MPEG-2 and MPEG-4

Visit the TV Forum




Standard Definition (SD) vs. High Definition (HD)


Standard definition (SD) television is broadcast at 720x480 resolution, which represents the number of lines in an image on your television. The more lines, the greater the definition and clarity of picture. Standard definition can also be referred to as 480i or 480p.


High Definition (HD) picture can be broadcast in either what's referred to as 720i / 720p (1280x720) resolution or 1080i/1080p (1920x1080) resolution. 1080 will offer you a higher resolution picture than 720, but both are considered to be HD.


Shaw offers a range of Digital Boxes which will either support standard definition alone, or both standard and high definition picture. More information on Shaw Digital Boxes can be found here: Shaw - Equipment


Standard Definition vs HD Resolutions



To learn more about cables and how they affect your television signal, visit Glossary of Cables and Connections



Back to top


Interlaced vs. Progressive Scan


When you hear 1080p and 1080i, you might not immediately understand the difference. The "p" and "i" stand for progressive and interlaced, and it refers to the way in which the picture appears on your television.


The interlaced image is comprised of two halves of the same image which appear in rapid succession, whereas with progressive imaging, pixels are refreshed in order, or simultaneously. This happens so fast that the human eye can't tell the difference, however in fast moving images such as scenes featuring fast vehicles, sports or fighting sequences, interlaced images can appear blurry.


When watching content with fast paced action, it may be better to watch something in 720p definition (the "p" stands for progressive) over 1080i (the "i" stands for interlaced), even though 1080 is technically higher definition than 720.


Interlaced Image

Interlaced Image Example


Back to top


MPEG-2 vs. MPEG-4


MPEG4 is a relatively new way of displaying high definition picture, and is not compatible with all models of Digital Cable Boxes provided by Shaw. If you are using an MPEG2 compatible box and attempt to access an MPEG4 channel, you may be able to hear the audio but the screen will be black or present an unauthorized message.


Much like computers and smart phones, cable system technology will be periodically improved so that you can receive the best viewing experience possible. Previous changes include the transition from analog to digital, as well as standard definition to high definition picture.


You can learn more about MPEG-4 compatibility at Guide to MPEG4 Channels and Digital Cable Boxes

MPEG-4 Compatible Shaw Hardware




Still Need A Little Help?

See what other customers are asking, or sign-in to ask

your own question, in the TV forum.