Specifications
Print2CAD OCR 2013 - 112
17.4.4 CMYK Color Space
“The CMYK color model (process color, four color) is a subtractive color model, used
in color printing, and is also used to describe the printing process itself. CMYK refers to
the four inks used in some color printing: cyan, magenta, yellow, and key black. Though
it varies by print house, press operator, press manufacturer and press run, ink is typically
applied in the order of the abbreviation.
The “K” in CMYK stands for key since in four-color printing cyan, magenta, and yellow
printing plates are carefully keyed or aligned with the key of the black key plate. Some
sources suggest that the “K” in CMYK comes from the last letter in “black” and was
chosen because B already means blue. However, this explanation, though plausible and
useful as a mnemonic, is incorrect.
The CMYK model works by partially or entirely masking colors on a lighter, usually
white, background. The ink reduces the light that would otherwise be reected. Such a
model is called subtractive, because inks “subtract” brightness from white. In additive
color models such as RGB, white is the “additive” combination of all primary colored
lights, while black is the absence of light. In the CMYK model, it is the opposite: white
is the natural color of the paper or other background, while black results from a full
combination of colored inks. To save money on ink, and to produce deeper black tones,
unsaturated and dark colors are produced by using black ink instead of the combination
of cyan, magenta, and yellow.”
Source: Wikipedia, subject “CYMK Color Space”
License Agreement: http://creativecommons.org/licenses/by-sa/3.0/
17.5 OCR Denition
“Optical character recognition, usually abbreviated to OCR, is the mechanical or elec-
tronic translation of scanned images of handwritten, typewritten or printed text into
machine-encoded text. It is widely used to convert books and documents into electronic
les, to computerize a record-keeping system in an ofce, or to publish the text on a
website. OCR makes it possible to edit the text, search for a word or phrase, store it more
compactly, display or print a copy free of scanning artifacts, and apply techniques such
as machine translation, text-to-speech and text mining to it. OCR is a eld of research in
pattern recognition, articial intelligence and computer vision.”
Source: Wikipedia, subject “OCR”
License conditions: http://creativecommons.org/licenses/by-sa/3.0/