Aspect Ratio

Aspect ratio refers to the shape of a TV picture and has two main formats:

• Most standard definition televisions have a 4:3 aspect ratio, which are nearly square.
• HDTVs have a 16:9 aspect ratio, also called wide-screen.

When a program and a television have different aspect ratios, the show is displayed with black bars to fill the extra space. A common example is a letterbox display, which is how a wide-screen movie is displayed on a 4:3 TV.

• The aspect ratio of a TV program is set by the broadcaster.
• For more information, see Why is a program displayed with black bars on the TV screen?

Resolution

Resolution relates to picture quality and is expressed by a number followed by a letter. The number refers to how many individual horizontal lines make up the image, while the letter (i or p) describes how the image is drawn:

• Interlaced scan (i): Half of the lines are drawn (every odd-numbered line, for example), and then the missing lines are drawn. This enables more lines to be transmitted, but it takes twice as long to complete one image.
• Progressive scan (p): All lines are drawn at the same time. Fewer lines can be transmitted at once, but the image is drawn twice as fast as an interlaced image.

Common TV resolutions range from a high of 1080p to a low of 480i. When comparing resolutions, if the number of lines is the same, a progressive scan image is preferable. For example, 1080p is a higher resolution than 1080i. 1080i is comparable to 720p.

Resolutions can be separated by category:

• High definition: 1080p, 1080i, 720p.
• Enhanced definition: 480p.
• Standard definition: 480i.

For more information on altering these settings on your Spectrum Receiver, see How do I change the aspect ratio and resolution?