Glossary
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National Instruments Corporation
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IMAQ Vision for LabWindows/CVI User Manual
C
caliper
(1) A function in the NI Vision Assistant and in NI Vision Builder for
Automated Inspection that calculates distances, angles, circular fits, and
the center of mass based on positions given by edge detection, particle
analysis, centroid, and search functions.
(2) A measurement function that finds edge pairs along a specified path in
the image. This function performs an edge extraction and then finds edge
pairs based on specified criteria such as the distance between the leading
and trailing edges, edge contrasts, and so forth.
center of mass
The point on an object where all the mass of the object could be
concentrated without changing the first moment of the object about
any axis.
chroma
The color information in a video signal.
chromaticity
The combination of hue and saturation. The relationship between
chromaticity and brightness characterizes a color.
closing
A dilation followed by an erosion. A closing fills small holes in objects and
smooths the boundaries of objects.
clustering
A technique where the image is sorted within a discrete number of classes
corresponding to the number of phases perceived in an image. The gray
values and a barycenter are determined for each class. This process is
repeated until a value is obtained that represents the center of mass for each
phase or class.
CLUT
Color lookup table. A table for converting the value of a pixel in an image
into a red, green, and blue (RGB) intensity.
color image
An image containing color information, usually encoded in the RGB form.
color space
The mathematical representation for a color. For example, color can be
described in terms of red, green, and blue; hue, saturation, and luminance;
or hue, saturation, and intensity.
complex image
Stores information obtained from the FFT of an image. The complex
numbers that compose the FFT plane are encoded in 64-bit floating-point
values: 32 bits for the real part and 32 bits for the imaginary part.
connectivity
Defines which of the surrounding pixels of a given pixel constitute its
neighborhood.
