Hardware manual

Impact Reference Guide Edge Point Find
3-105 Datalogic Automation Inc.
Line Segment The x and y coordinates of the beginning and end of the edge-finding
line
Line Segment List A list of all the line segments between edges found
Noise Level The amount of background noise present in the image. Higher noise
means the edges must be farther apart. Lower noise allows edges that
are closer together.
Maximum Number
Of Edges To Find
Limits the number of edges found to those with the strongest transitions
Edge Pattern The edge pattern to find (Rising indicates a transition from dark to light;
Falling indicates a transition from light to dark)
All edges
Alternating Rising/Falling
Alternating Falling/Rising
Rising Only
Falling Only
Central Rising Edge
Central Falling Edge
Edge Detection
Method
Gradient Edges or Grey Level Edges
Gradient detection generally provides more consistent results. In some
cases Gradient detection can pick up extra edges in a noisy image and
Grey Level detection may offer better control.
See “Edge Detection Method” on page 3-78.
Edge Detection
Sensitivity
The sensitivity level
Determines the transition level necessary for detection. A higher value
detects more edges.
The non-fixed uses adaptive threshold selection. See “Threshold Types”
on page 3-186.
Fixed Threshold uses the Adaptive Grey Level Threshold Offset fixed
value.
Fixed Gradient
Threshold Percent-
age
The gradient threshold value for Fixed Threshold Edge Detection Sensi-
tivity (0 to 100 percent)
Fixed Grey Level
Threshold Percent-
age
The grey level threshold value for Fixed Threshold Edge Detection Sen-
sitivity when Grey Level Edge detection is selected (0 to 100 percent)
Adaptive Grey
Level Threshold
Offset
If one of the adaptive settings is picked from Edge Detection Sensitivity,
and Grey Level Edges is selected, then this offset is added to the adap-
tive threshold. This allows you to weight the adaptive threshold up or
down.
Subpixel Method The type of subpixel averaging
The grey levels of adjacent pixels (1, 3, 5, 7, or 9) around an edge point
are averaged and used to interpolate the edge to a fraction of a pixel.
Subpixel Position The subpixel position for edges that are not well defined. See “Subpixel
Position” on page 3-144.
Input Name What it is