IMAQ Count Objects 2 (Bounding Box tracking outside Frame)

[Nik1]

Hi,

I'm feeding in a video, which is scanning along a large area and using the IMAQ Count Objects 2 VI to recognise certain objects on the surface. Im extracting the centre of mass position of the object via the bounding box/ROI that is fitted around each object recognised by the VI to work out the spatial shift everytime the scanner moves along the area. I'm having an issue when an object is entering or leaving the frame since the bounding box forms a smaller & smaller box around whatever is left of the object therefore providing a false centre of mass (c of m) position, I'm looking to get the actual (c of m) position and not the c of m position of the object remaining in the frame.
So I guess the question is, is it possible to have a bounding box or ROI that doesn't stop at the borders of the frame? Or another VI that can do something along these lines.

[Nik1]

bump

[Andy.G]

Hi Nik,

I’m a little unsure as to what exactly you are trying to achieve, perhaps you could provide a copy of your code for me to look at so I have a better idea of what has been implemented thus far. Please could you comment out the code so as to ensure I know what you are trying to achieve within each section.

[Nik1]

Hi Andy,

The code is quite big and it would take quite some time to annotate. What I'm trying to ask is, the boundary box that is formed around any object detected when using IMAQ Count Objects 2.VI, can it also be implemented to track objects that leave the image frame? I need the information from the boundary box, specifically the centre of mass position of the object it is tracking. And when an object is entering the image frame or leaving the frame, the boundary box only forms over however much of the object is left in the frame and not the actual size of the object (half of which may be outside the image frame).
Or would another method be more suitable for this? Essentially Im trying to figure out the movement between each frame in the video by tracking objects that appear in the frame.

[Andy.G]

Hello Nik,

I’m not hugely familiar with that function in particular; however I have found a useful online document which demonstrates the applications of that particular function. Let me know if this helps.

[Nik1]

Hi Andy,

I've already seen this document, it isn't particularly helpful. Thanks anyway.

[Andy.G]

Hi Nick,

let me look into this a little further, I will have a chat with the vision experts here at NI UK and I will get back to you on this.