Raster images

A raster image (a bitmap) is a representation of pixels put together to make an image. Raster images are stored in image files with various formats.

This is a raster image

Imagine the smiley face in the top left corner as an RGB bitmap image. When zoomed in, it might look like the big smiley face to the right. Every square represents a pixel. Zooming in further, one can analyze three individual pixels, with their colors constructed by adding the values for red, green and blue.

Each pixel has an individually defined colour. For instance, a typical JPEG image often consists of colored pixels defined by three bytes — one byte each for red, green and blue.

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