Overview: Aspect ratios

Aspect ratios describe the shapes of the stored pixels and the intended displayed picture.

A pixel grid and a displayed rectangle need not have the same proportions. Pixel shape connects the stored dimensions to the intended display shape; anamorphic video makes that distinction especially visible. The three topics here supply the terms needed to describe that geometry accurately.

• Display aspect ratio
  Display aspect ratio is the intended width-to-height ratio of the displayed video picture.

• Pixel aspect ratio
  Pixel aspect ratio describes how wide each video sample is intended to appear relative to its height.

• Anamorphic video
  Anamorphic video stores a picture with a different sample-grid shape from its intended display shape.