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Bitmap vs vector

Bit-mapped and vector graphics are two different methods of representing images on a computer. Bit-mapped graphics store images as a grid of pixels, each with its own colour value, while vector graphics use mathematical formulas to define shapes such as lines and curves. Each type has its own advantages and disadvantages depending on how the image is used, particularly in terms of quality, file size, and scalability.

Bit-mapped

Vector

  Bit-mapped Vector
Example usage Photographs and detailed images. Logos, icons, diagrams and illustrations.
How the data is stored Stored as a grid of pixels, each with its own colour value. Stored as mathematical formulas describing shapes (lines, ellipse, polygons).
File Size Resolution dependent – increasing the number of pixels results in a larger file size.

Detail dependent – increasing the number of objects results in a larger file size.

 
Scalability Resolution dependent – becomes pixelated when scaled. Resolution independent – can be scaled with no loss of quality.
Advantages
  • Individual pixels can be edited.
  • Good for detailed images (e.g. photos).
  • File size remains the same if resolution is unchanged.
  • Individual objects/attributes can be edited.
  • Can be scaled without quality loss.
Disadvantages
  • File size increases with higher resolution.
  • Image quality decreases when enlarged.
  • File size increases as more objects are added.
  • Not suitable for highly detailed/realistic images.
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