Edge Strength Profile

[Andrew Ness]

I am using the imaqFindEdge function to do edge detection in my own C application. I need to provide the ability to control the threshold, width and steepness settings from the application's user interface. I would like to display an edge strength profile like that in the NI Vision Assistant Find Straight Edge Setup so that the user of the application can see a visual representation of the settings. I can display a line profile but I am having trouble figuring out how to obtain the edge strength profile. I tried using imaqEdgeTool2 but that only returns the edges that break the threshold, not the entire profile. Any suggestions would be greatly appreciated.

Thanks.

[nipun]

Hello Andrew,

Thank you for using our discussion forums. You can use the function, "imaqROIProfile" to get the profile information along the line. If you are using LabWindows/CVI there is a shipping example that is included with NI-IMAQ that shows this process. Please refer to the Edge Detection example installed under the ..\National Instruments\CVI70\samples\Vision\2. Functions\Caliper folder. I hope this helps you out. Have a great day!

Regards,
Nipun M
Applications Engineer
National Instruments

[Andrew Ness]

Hi Nipun,

Thanks for getting back to me. "imaqROIProfile" returns the same information as imaqLineProfile, but enables you to use any path. Applying this function to a straight line yields the same result as imaqLineProfile. I am trying to graph the edge strength profile, not just the profile of the pixels along the line/path. I'm trying to figure out how to convert this type of profile to an edge strength profile as I haven't been able to find an IMAQ function that returns this information.

Thanks,
Andrew

[pawslee]

dear Andrew
I am having the same problem in getting the data out of edge strength profile (ie to export it to a spreadsheet) etc. Have you found a method to do this?
Thanks
Alex

[Torba]

Hello Alex,

Thank you for contacting National Instruments.  There is a knowledgebase (KB) entry that talks about this.  Here is the link:

Creating an Edge Strength Profile

Regards,

Mike T

National Instruments