Defining Centroid with Vision AI in VB

Question

I'm usnig NI Vision Automated Inspection.  Any centroid related help that I've found references the centoid function for the development software.  
Can anyone point me in the right direction for using NI Vision AI to write VB code to acccomplish this? 
I've already gotten the acquisition up and running. 
Thanks, 
Bryan 

Answer 1

It sounds like there is some confusion about Vision Builder AI and the Vision Development Module (where Centroid2 can be used). Vision Builder AI is a configurable environment for designing Vision applications. It has a step called Detect Objects that allows you to specify threshold parameters and particle filtering data to remove unwanted objects and it returns data for all the resulting objects found (including the center of mass). You can control a Vision Builder AI engine that is running on your local machine or on a remote target using the Vision Builder AI API. We recently released C support for this API in Vision Builder AI 2011, which includes a dot net example for C# and VB. This would allow you to retrieve the results for the detect object step, but the algorithm would run in the Vision Builder AI engine. Using this method would tyopically mean that all your image processing/acquisition happen within Vision Builder AI, and you just use Visual Basic to control when the Vision Builder AI engine acquires an image and processes it, but you couldn't control which algorithms it runs since this can only be defined from within the Vision Builder AI environment when you create an inspection.
The Vision Development Module is a set of vision algorithms that are meant to be called from programming languages like LabVIEW, CVI, VB, MSVC, etc. It sounds like you are using this library in Visual Basic, and if this is the case, you don't need Vision Builder AI to do the detect object step since this will go through many other layers of SW to accomplish what you want, and calling the Vision Development algorithms directly will be much more direct. Is there a reason you want to use Vision Builder AI instead of the Vision Development Module algorithms included in the ActiveX control it sounds like you are using? To get help on the ActiveX Vision Analysis library, you can go to Start>> Programs>>National Instruments>>Vision>>Documentation>>NI Vision and open the cwimaq.chm.
If all you're doing is trying to find the center of mass, using the Vision Development Module is much more straight forward than trying to create a Vision Builder AI inspection, which you control from Visual Basic and get the resuls of the inspection to figure out the center of mass from one of the steps in the inspections.
Hope this helps,
Brad