Dalsa ML Series, Руководство пользователя

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40  Camera Performance and Features Linea ML Color Cameras
Image Filters
Relevant Features: imageFilterMode , imageFilterType , imageFilterKernelSize ,
imageFilterContrastRatio
The camera has a selection of image filters that can be used to reduce image noise.
Use the feature imageFilterMode to turn the filtering on or off. Use the feature imageFilterType to
read the user information of the type of filter that is being used. In this case, a weighted average
filter is applied.
Kernels
Use the ImageFilterKernelSize feature to select the number of pixels involved in the filter or the
kernel size. The options are: 1 x 3, and 1 x 5 filter kernels. The 1 x 3 and 1 x 5 filter kernels are
“weighted average” filters.
The 1 x 3 filter kernel uses 75% of the original pixel and 12.5% of the adjacent pixels.
12.5
%
75%
12.5
%
Figure 18: 1 x 3 kernel
The 1 x 5 filter kernel uses 50% of the original pixel and 12.5% of the adjacent two pixels on both
sides of the original pixel.
12.5
%
50%
12.5
%
12.5
%
12.5
%
Figure 19: 1 x 5 kernel
Image Filter Contrast Ratio
The image filter contrast ratio feature is used to determine when the filter is applied to the image
data. The control looks at the ratio between two adjacent pixels (prior to filter processing) on the
sides of the relevant pixel and determines the difference or contrast between those pixels. If the
contrast ratio is greater than the value set by the user, then the filter automatically turns off for
those two pixels. If the contrast is below the set value, then the pixel filter is applied.
A value of 0 will turn off the filters for all pixels and a value of 255 will keep the filter on for all
pixels.