Rockwell Automation 5370-CVIM2 Module - Manual (Page 276)

Chapter 7
Inspection Tools
7–38
Note in Figure 7.33 that the Max and Min values are 100000 (using scientific
notation: 1e+05) and 0, respectively. These are the default area values in
pixels. In this case, since the area of each black object in the window lies
somewhere between 0 and 100000 pixels (and no other measurement
functions are active) each contour has a yellow border.
If you already know the maximum and minimum area values for your
application, you can enter those values directly by picking the
Max and Min
fields. If not, you can use the Pick Target function to measure the area of the
appropriate objects, then enter the appropriate high and low area limit values
directly into the
Max and Min fields. (Refer to the Pick Target Panel section,
on page 7–43, for details.)
As a result of these Max and Min settings, the contour window will count as
objects only those contours of the selected color whose area is within the
selected limits.
Generally, contours that satisfy the limits of all of the active measurement
functions (when two or more measurement functions are active) are
displayed with a yellow border, and thus qualify as objects. On the other
hand, if no measurement functions are active, all contours (of the selected
color) qualify as objects.
NOTE: In some cases there may be too many contours to process; thus, no
contours will be displayed regardless of the status of the measurement
functions or their limit settings, and no objects will be counted. An
appropriate error message will be displayed when you select “
Nominal ” to
“learn” the number of objects. If this occurs, you can increase the “scratch”
memory size in the configuration editor (
Inspection panel) or use
morphology to decrease the complexity of the image.
Center Column –– This column selects the status of a measurement
function as active (
Y ) or inactive ( N ). When a specific measurement function
is active, its range limits determine which contours qualify as objects insofar
as that measurement function is concerned. However, in order for any
contour to qualify as an object, its measurement values must satisfy the limits
of all active measurement functions.
Left Column –– This column uses a “
)” or “*” symbol to select one of the
measurements as the basis for ordering the contours in the image field.
Contours are ordered in either ascending or descending order according to
the selected measurement parameters. Ordering the contours is provided for
math tools and communication messages.
The order of the numbers is determined by both the selected measurement
and the symbol. Figure 7.34 (page 7–39) provides some examples that
illustrate this relationship. Note the changes in the locations of the numbers.