Epson Perfection 610 User Manual page 60

pixel
resolution
scan
Threshold
Glossary
Short for picture element. Every image is composed of a number of
pixels. Pixels are also counted in units of dots.
Indication of how finely an image is resolved into pixels. Measured in dots
per inch (dpi), pixels per inch (ppi), or samples per inch (spi).
An operation performed by the sensor and the carriage of a scanner. The
sensor "reads" the colors in an image, and sends the color information to
the computer as digital data.
An EPSON TWAIN option that sets the point at which gray values in an
image are represented as either black or white.
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