National Instruments IMAQTM - Manual (Page 15)

Chapter 1 Introduction to IMAQ Vision
© National Instruments Corporation 1-5 IMAQ Vision for Visual Basic User Manual
Tip Refer to the source code of the CWMachineVision control for an example of how to
use the CWIMAQVision methods.
ActiveX Objects
Use the objects to group related input parameters and output parameters to
certain methods, thus reducing the number of parameters that you actually
need to pass to those methods.
Note ActiveX objects in cwimaq.ocx have a CWIMAQ prefix, objects in niocr.ocx
have an NIOCR prefix, and objects in cwmv.ocx have a CWMV prefix.
You must create an ActiveX object before you can use it. You can use the
New keyword in Visual Basic to create these objects. For example, use the
following syntax to create and store an image in a variable named image :
Dim image As New CWIMAQImage
Tip If you intend to develop an application in Visual C++, National Instruments
recommends that you use IMAQ Vision for LabWindows/CVI. However, if you decide
to use IMAQ Vision for Visual Basic to develop applications for Visual C++, you can
create objects using the respective Create methods on the CWIMAQVision control or
CWMachineVision control. For example, to create a CWIMAQImage object, use the
CWIMAQVision.CreateCWIMAQImage method.
Creating IMAQ Vision Applications
Figures 1-1 and 1-2 illustrate the steps for creating an application with
IMAQ Vision. Figure 1-1 describes the general steps for designing a
Vision application. The last step in Figure 1-1 is expanded upon in
Figure 1-2. You can use a combination of the items in the last step to create
a IMAQ Vision application. For more information about items in either
diagram, refer to the corresponding chapter listed beside the item.
Note Diagram items enclosed with dashed lines are optional steps.