Edge PresencePlus P4, Руководство пользователя

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01/05
P/N 120413
167
User’s Manual Glossary
Banner Engineering Corp. • Minneapolis, MN USA
www.bannerengineering.com • Tel: 763.544.3164
f/stop (or f/number)
Ratio of the focal length of a lens to the diameter of its
opening. Increasing or decreasing an exposure by one f/stop
doubles or halves the amount of light allowed through the
lens.
G
gradient magnitude
The rate-of-change of pixel intensities over a small local
neighborhood.
gray scale
Standardized variations of values from white, through shades
of gray, to black in a digitized image with black assigned the
value of zero and white the value of 255.
H
halogen
A gas, such as iodine, placed inside an incandescent lamp to
gather the evaporated filament off the bulb and redeposit it
back onto the filament.
high pass filter
A processing operation that enhances high frequencies (and
attenuates low frequencies).
histogram
Frequency counts of the population of pixels of each intensity
(gray level) or other characteristic populations in an image.
I
incandescent
Thermal generation of light, usually through radiant filaments
in a bulb.
incident light
The light falling directly on an object.
inverse square law
The exponential relationship between increased distance and
decreased light intensity.
iris
An adjustable aperture built into a Sensor lens to permit
control of the amount of light passing through the lens.
L
LED
Acronym for Light-Emitting Diode.
M
mask
A pattern used to eliminate portions of another pattern.
Regions of an image at a constant value, usually white or
black, form the mask.
N
noise
Irrelevant or meaningless data resulting from various causes
unrelated to the source of data being measured or inspected;
random undesirable video signals.
O
OCR
Acronym for Optical Character Recognition. Recognition of
each character in a string by a vision system.
P
parallax
The difference in appearance or position of an object when
viewed from two different locations.
photon
A particle of light. A quantum of electromagnetic energy
moving at the speed of light.
pincushion distortion
A visual effect where the sides of an image appear to bulge
inward on all sides like a pincushion. Caused by an increase
in effective magnification, as points in the image move away
from the image center.