How do I draw region of interest?

[Ranger94]

I am new to Labview module. I am working on vehicle detection on road presently i have completed threshold operation now I need to draw a ROI across the Vehicles. Please help me with some ideas or tools to draw the ROI

[wiebe@CARYA]

Use the Vision Development Module.

[altenbach]

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@Ranger94 wrote:

I need to draw a ROI across the Vehicles. 

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The answer depends on what you use to "draw" or represent the vehicles on he front panel. (e.g. picture, dots on an xy graph, levels on an intensity graph, etc.). Can you tell us more?

[Bob_Schor]

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@Ranger94 wrote:

I am new to Labview module. I am working on vehicle detection on road presently i have completed threshold operation now I need to draw a ROI across the Vehicles. Please help me with some ideas or tools to draw the ROI

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I hope your first sentence was really meant to be "I'm new to the LabVIEW Vision module", implying that you are not new to LabVIEW, itself.  LabVIEW Vision is (compared to many other parts of LabVIEW) somewhat under-documented, handles data in "unusual" ways, and is one of the more challenging modules that I have encountered.

Regarding the ROI -- are you planning to look at an image and draw the ROI yourself, using a mouse?  Are you planning to have LabVIEW analyze the image and decide (for itself) where to put an ROI programmatically?  You can, of course, do both of these things, but the "how to" is a little different ...

It might also be helpful to see some of your code to (a) get a better idea of what you are trying to do, and (b) get an idea of your "comfort" with LabVIEW Vision.

Bob Schor

[Ranger94]

 Sir, I want LabVIEW to analyze the image and decide (for itself) where to put an ROI programmatically. 

And pardon me for the mistakes I shall try to be more accurate with my questions from next time.

[Ranger94]

LabVIEW analyze the image and decide (for itself) where to put an ROI programmatically and draw an rectangular ROI across the objects in the foreground. 

[wiebe@CARYA]

What is the exact problem? We can't help you detect cars automatically, that is way to broad. So I'll assume you get ROI's from your routine and want to draw them (the title or the thread).

Have you've read this: Region Of Interest Frequently Asked Questions (FAQ)?

Or this: NIVision for LabVIEW User Manual?

[Ranger94]

sir, I am attaching two image files 

1. grey scale image

2.After thresholding(best i can come up with)

My problem is i want to reflect a Rectangular ROI across my grey scale image after gathering useful data from the thresholded image

[wiebe@CARYA · Accepted solution]

To find\label objects look at IMAQ Count Object (Machine Vision»Count and Measure Objects).

[Bob_Schor]

Ranger94,

     I asked if you wanted to (interactively) draw the ROI, or have LabVIEW programmatically do so according to some (as yet unspecified) criteria.  As best as I can understand, you said "Yes" to both, but failed to elaborate what you really meant.  Weibe provided some useful references, including how to draw your own ROI, but your followup Post suggested you haven't read it, or at least you didn't respond to it.

     Have you considered trying to hire a LabVIEW Developer with expertise in using NI Vision?  This is one of the more "challenging" LabVIEW Modules, particularly without a colleague or LabVIEW Guru to provide help and encouragement as you try to get a handle on some of the key Concepts (like the idea of an "Image").

Bob Schor