Bitmap font

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A character from a bitmap font in the original and enlarged 10 times

When bitmap font is called a digitally recorded font for the computer in the file, the shapes of the letters as in an image file as mostly monochrome raster graphics are stored.

properties

Bitmap fonts can only be enlarged and reduced in size to a very limited extent, as details are always lost when raster graphics are scaled, which reduces the legibility of the characters. One way out would be to keep different versions of the font in all possible sizes. Because of the high memory requirements, vector fonts such as TrueType and PostScript are mostly used today.

Comparison to vector fonts

advantages

  • Bitmap fonts are displayed faster because vector fonts must first be rasterized before they can be displayed.
  • The representation of bitmap fonts is easier to implement.
  • If the bitmap font is to be displayed in a size in which the characters are available, pixel-perfect display is possible.

disadvantage

  • To display different font sizes, the font must either be scaled using interpolation methods , which entails a loss of quality, or it must be available in different sizes, whereby the memory requirement increases accordingly.
  • If no data compression is used, the memory requirement grows quadratically with the font size (with double the font size, each letter consists of four times as many pixels).

use

In graphics-capable pocket calculators , car radios and other technical devices, in addition to segment displays , matrix displays are often used, which display bitmap fonts with characters typically 5 × 7 pixels in size. Bitmap fonts are also used in devices with LCD screens where the display of vector fonts would be too slow and where no print output is required, such as cell phones or PDAs .

In addition, they are used as so-called "screen fonts" in PostScript fonts for screen output on devices that cannot display Postscript fonts by themselves (see also Adobe Type Manager ) .

Web links

Commons : Bitmap Fonts  - collection of images, videos, and audio files