Manual

DobotVisionStudio User Guide
Issue V4.1.2 (2022-06-08) User Guide Copyright © Yuejiang Technology Co., Ltd.
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- Strongest Edge: only the edge point set with the largest gradient in the
scanning range is detected and fitted into a circle.
- Last Edge: only the edge point set with the largest distance from the center
of the circle within the scanning range is detected and fitted into a circle.
- First Edge: only the set of edge points with the smallest distance from the
center of the circle within the scanning range is detected and fitted into a
circle.
• Edge Polarity: it has three modes, including dark to light, light to dark and any.
- Dark to light: it means that the transition from the area with a low gray value
to the edge of the area with a high gray value.
- Light to dark: it means the transition from the area with a high gray value to
the edge of the area with a low gray value.
- Any means both edges are detected.
• Edge Threshold: The edge threshold is the gradient threshold, ranging from 0 to 255. Only
edge points whose edge gradient threshold is greater than this value are detected. The larger the
value is, the stronger the anti noise ability is, the less the number of edges is, and even the target
edge points are screened out.
• Filter Size: it is used to enhance the edge and suppress noise, and its minimum value is 1.
When the edge is blurred or there is noise interference, you can increase its value to make the
detection result more stable. If the distance between the edge and the edge is smaller than the filter
size, it will affect the accuracy of the edge location or even lose edge. This value needs to be set
based on the actual situation.
• Calipers Number: it is used to scan ROI area quantity of edge points, as shown below.
• Reject Number: It means that the number of minimum points that have high error to be
excluded from fitting. In general, if there is a great number of points excluded from fitting, its value
should be set higher. For better results, it is recommended to use it in combination with the parameter
of distance to remove.
• Initial Locating: If it is enabled, combined with the circular location sensitivity and
subsampling coefficient settings, this parameter can roughly determine that the center of the area
closer to the circle in the ROI area used as the initial circle center, which is convenient for subsequent
fine circle search. If the initial location is disabled, the ROI center is the initial circle center by
default. Under normal circumstances, the previous module of finding circle is position correction,
it is recommended to disable this parameter.