Mark an object in real time on a displayed video acquired from an USB camera

[LePhuong]

Hello,

I am a beginner LabView user undertaking a project in which I need to show video acquired from an USB camera in LabView on computer screen. In the video, there will be a metal part, which is always be at a fixed position at the bottom left of the view. I need to mark an arrow alike sign on the metal part, please take a look at the attached picture. To recognize the metal part easier, in the picture, I drew a blue line at the boundary of the part, whilst the arrow was green. The arrow must be radially pointed to the center of the blue line (but, the blue line may not need to be created) and must be there every time I start the VI, throughout the video.

How should I do to display the video? Is there any way to create the arrow in LabView (either by programming or manually drawing the arrow)? If making the arrow is impossible, is there any way to just mark a cross at the center of the blue line? The blue line does not need to be marked on the video.

I have LabView 2010 with Vision Development Module. My camera can be found under NI IMAQdx devices in Measurement and Automation Explorer.

Thanks,

LePhuong

[LePhuong]

Just to update. I've known how to display the video already. I've also found that IMAQ Overlay Functions can be used to superimpose objects to an image. However, I am not so sure how to apply on video? May be I need to continuously grab every frame of the video, then insert the desired object to each frame, and then show back the modified images?

Thanks!

[Silver_Shaper · Accepted solution]

Hi,

Look at this post. It may help you. http://forums.ni.com/t5/Machine-Vision/pattern-matching-program/m-p/1914589#M34855. In here its video signal you can replace this with the live video.

[LePhuong]

Hi ₰αÇ, 

I downloaded your VI and learned a lot from it. Many thanks.

I also built up a VI for pattern recognition and have some troubles. Could you take a look and help to address them? http://forums.ni.com/t5/Machine-Vision/How-to-use-IMAQ-Match-Pattern-with-the-displaying-video-is-in...

Thank you in advance.