Owais,
You may have looked already, but there are a few example programs that can definitely get you started. If you open the LabVIEW example finder, click the Browse tab and the Task button. On the right find Hardware Input and Output >> IMAQ >> High Level and there is a VI called HL Grab.vi which is a continuous acquire VI. If you look at the block diagram you can see that it is creating a image line then using that to acquire images.
Assuming that your two cameras are each hooked up to a different card, you can essentially double the main VI's in the code for a second acquisition. Then in the loop at the end where it displays the image you could put in an image subtraction and then display the result as well. Make sure that you make a separate image buffer (by using the IMAQ Create.vi) for the newly subtracted image to be stored in. Let me know if you have more questions about the specifics, thank you!
-Allison S.
Applications Engineering
-Allison S.
Calibration Services
Product Support Engineer
