Chapter 2: Resolution

Video resolution is very important, but also includes lots and LOTS of numbers - which can make it confusing.

Every frame, or image, is made up of a series of tiny dots (called pixels). The more pixels you have, the better quality the picture. Easy, right?

Well, first we have our SDTV (Standard Definition) formats:

PAL (the British format) displays video at 720 x 576 pixels. On the diagram below that's the red and yellow areas combined. That means the screen has 576 squares or dots along each row, and 480 going top to bottom (that's 415,000 pixels - or 0.4MP - much less than your digital camera).

NTSC is similar, but is only 720 x 480 pixels. That's 350,000 pixels, or 0.35MP (about the same as a very cheap webcam, believe it or not!). NTSC is the red area, below.

HDTV (High Definition) formats also come in three different types:

When you buy a HDTV, they come in 3 types: 720p, 1080i & 1080p. But what do they mean?

The first one is 720p (the green rectangle) - this means that the resolution is 1280 x 720 pixels. We're up to 0.9MP now, so we're getting there! This is a slightly cheaper way of getting a HDTV, because the display is cheaper to make.

Some TVs are advertised as 1080i or 1080p. The resolution here is 1920 x 1080 (2.1MP) and is about the best quality you can get. That would be the blue rectangle.

Lots of people ask what the i and the p stand for - but this is a bit more detail than you need to know right now. If you're buying a TV, I would go with the 'p' because you get a little bit less motion blur during action scenes. But you don't really need to know why that is for your coursework.

Reproduced with kind permission from Mark Clarkson, from the originial source