National Instruments ISC-1762, Руководство пользователя

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NI 17xx Smart Camera User Manual
as white, the highest pixel value. In Figure 3-4c, several bright areas of the image have been
clipped to the maximum pixel value, and you can no longer distinguish subtle shading in the
brightest areas of the image.
Gain can be useful when there is not enough available light and you need to increase the
brightness of your images. However, increasing gain multiplies both the signal and noise. When
possible, it is preferable to add additional lighting.
Hardware Binarization
The NI Smart Camera supports binarization and inverse binarization of acquired images.
Binarization and inverse binarization segment an image into two regions—a particle region and
a background region. Use binarization and inverse binarization to isolate objects of interest in an
image.
To separate objects under consideration from the background, select a pixel value range. This
pixel value range is known as the gray-level interval, or the threshold interval. When enabled,
binarization sets all image pixels that fall within the threshold interval to the image white value
and sets all other image pixels to black. Pixels inside the threshold interval are considered part
of the particle region. Pixels outside the threshold interval are considered part of the background
region.
Inverse binarization reverses the assigned bit numbers of the particle region and the background
region. All pixels that belong in the threshold interval, or the particle region, are set to black, and
all pixels outside the threshold interval, or the background region, are set to the image white
value.
Figure 3-5 illustrates binarization and inverse binarization.
Figure 3-5.
Binarization and Inverse Binarization
NORMAL
Stored V
alue
Sampled Data
INVERSE
Stored V
alue
Sampled Data