OCR-A

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OCR-A
font OCR-A
category Grotesque
Creation 1968
example
Font example for OCR-A
Special OCR-A control characters " hook ", " fork " and " chair "
An example in OCR-A

OCR-A was developed in 1968 as the first optically machine-readable font according to the specifications of the US government . It is specified in ANSI INCITS 17-1981, as well as DIN 66008 "Font A for machine optical character recognition". OCR is the abbreviation for English. optical character recognition = " optical character recognition ".

OCR-A is mainly used for forms and other documents that are to be recorded by machine. Recently, the typeface has been rediscovered by designers who wanted to give their documents a cool, impersonal and machine-like look. The typescript can be found in many scene papers, in music magazines, on book covers and in multimedia and video productions.

Some time later, Adrian Frutiger developed the less abstract OCR-B , which was raised to the ISO standard in 1973 .

Coding

OCR fonts are primarily used to input normal characters into computer systems; the read characters are coded exactly like typed characters.

OCR-A contains a few additional characters to structure the input forms and to control the character recognition, as in the adjacent figure the three OCR-A symbols " hook ", " fork " and " chair ". These symbols are used to trigger special signals via the scanner, for example to signal the end of the current line. For these, Unicode defines its own code positions in the Unicode block optical character recognition .

Implementations

As classic typesetting was increasingly being replaced by typesetting with the computer, Tor Lillqvist developed a digital definition of the type using MetaFont . This definition has been improved by Richard B. Wales and is available from CTAN .

To make this free version of the font accessible to Microsoft Windows users, John Sauter created TrueType files from it in 2004 using the programs potrace and FontForge . In 2008, Luc Devroye corrected the vertical positioning and the name of the small z .

Matthew Skala, unknown to John Sauter's work, created another TrueType version of the font in 2006 using mftrace .

Web links

Commons : OCR-A  - collection of images, videos and audio files

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  1. The Unicode Standard 5.0, Section 15.6: Optical Character Recognition: U + 2440-U + 245F
  2. The MetaFont source code for OCR-A in the CTAN ( Memento of the original from June 25, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.ctan.org
  3. John Sauter's OCR-A font
  4. Jump up ↑ Luc Devroyes Font Page, search for Sauter to find the font
  5. Matthew Skala on his versions of the OCR fonts ( Memento of the original from April 18, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / ansuz.sooke.bc.ca
  6. The OCR fonts on Matthew Skala's page