Rockwell Automation 5370-CVIM2 Module - Manual (Page 306)

Chapter 7
Inspection Tools
7–68
X Edge, Y Edge Kernels
The X Edge and Y Edge kernels perform directional spatial filtering
functions that sharpen gradients lying along the Y–axis of the image ( X
Edge ) or the X–axis ( Y Edge ). (Note that the effect is similar to that of the
Sobel kernels, except that the X Edge ’s 5x5 kernel produces a wider
gradient than the Sobel X ’s 3x3 kernel.) The kernels for these two functions
use the same coefficient values, but these values are arrayed differently in
each kernel.
X Edge Kernel –– The coefficients in the X Edge kernel are arrayed in a 5x5
matrix, as follows:
1 1
1
2
2
4
0 –1
–1
–2
–1
0 –2
0 –4
1 2 –1 0 –2
1 1 0 –1 –1
Figure 7.57 illustrates the effect of the X Edge kernel on a dark object on a
light background.
Figure 7.57 Example: Effect of X Edge Kernel on Inspected Object
Image tool
Inspected
object