National Instruments IMAQTM 用户手册
Chapter 5
Performing Machine Vision Tasks
5-10
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Finding Lines or Circles
If you want to find points along the edge of an object and find a line
describing the edge, use
describing the edge, use
CWMachineVision.FindStraightEdge
and
CWMachineVision.FindConcentricEdge
.
CWMachineVision.FindStraightEdge
finds edges based
on rectangular search areas, as shown in Figure 5-5.
CWMachineVision.FindConcentricEdge
finds edges based
on annular search areas.
Figure 5-5. Finding a Straight Feature
If you want to find points along a circular edge and find the circle
that best fits the edge, as shown in Figure 5-6, use
that best fits the edge, as shown in Figure 5-6, use
CWMachineVision.FindCircularEdge
.
1
Search Region
2
Search Lines
3
Detected Edge Points
4
Line Fit to Edge Points
2
1
4
3