OCR is a field of research in pattern recognition,
artificial intelligence and machine vision. Though academic
research in the field continues, the focus on OCR has shifted
to implementation of proven techniques. Optical character recognition
(using optical techniques such as mirrors and lenses) and digital
character recognition (using scanners and computer algorithms)
were originally considered separate fields. Because very few
applications survive that use true optical techniques, the OCR
term has now been broadened to include digital image processing
as well.
Early systems required training (the provision
of known samples of each character) to read a specific font.
"Intelligent" systems with a high degree of recognition
accuracy for most fonts are now common. Some systems are even
capable of reproducing formatted output that closely approximates
the original scanned page including images, columns and other
non-textual components.
