text: Optical | NIST
  www.nist.gov/srd/nist-standard-reference-databases-optical
  Often abbreviated as OCR, optical character recognition refers to the branch of computer science that involves reading text from paper and translating the images into a form that computers can manipulate (like ASCII codes, for instance). An OCR system enables a user to take a book or journal article, feed it directly into an electronic computer file, and then edit the file using a word processor.
  NIST has long been prominent in developing databases that enable users to harness computers to access printed documents.
  Special Software 1 NIST Scoring Package, PC, DG
  Special DB 2 NIST Structured Forms Reference Set of Binary Images, PC, DG
  Special DB 6 NIST Structured Forms Reference Set of Binary Images II, PC, DG
  Special DB 8 NIST Machine-Print Database of Gray Scale and Binary Images, PC, DG
  Special DB 19 NIST Handprinted Forms and Characters, PC, DG
  Special DB 20 NIST Scientific and Technical Document, PC, DG
  Special DB 25 NIST Federal Register Document Image Database, PC, DG
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