Epson Expression 1680 - Manual (Page 142)

4 Glossary
subtractive primary colors
The colors of cyan, magenta, and yellow (CMY) which produce black when mixed
in certain amounts. In printing, black is often added to give more definition as
mixing of actual inks cannot produce pure black.
terminator
A device that stops electronic signals, and prevents them from proceeding or
returning to other devices. This is necessary to stop a signal from continuously
reflecting between devices.
threshold
A reference point that is used to determine whether data will be processed as
“on” or “off.” In the case of color image data, “on” means that a certain color will
appear in a pixel or dot, and “off” means that color will not appear there.
tone correction
A method of adjusting the tone curve so that the reproduction results on different
types of output devices have gradations similar to the original image.
tone curve
The graph that shows the contrast ratio between the input (original image) and
output (image data) in image processing.
unsharp mask
Originally a photographic process in which a sharply focussed and a slightly out-
of-focus image are combined to produce a sharper image. This process is
simulated by software to produce the same effect.