IMAQ Copy - Data does not stick around

[-lisa]

Hello,

First off, Thank you in advance for any help you can offer.

I am rather new to LabVIEW – so I may have made an obvious mistake.

I am continuously capturing video images in my buffer (works fine). 

I would like to use the 100^th frame from the camera & subtract it from all future frames. I am using the “IMAQ Copy” to save the 100^th frame to an item called Copy_of_Image. 

For some reason Copy_of_Image does not keep the image data.  And I don’t know why.  I don't think I'm using IMAQ Copy correctly.  (I know it produces a reference to the destination image, but how do I access the image data?)

My code is attached.

Thanks,

- lisa

(Lab VIEW 8.2 most recent versions of IMAQ/Vision)

Message Edited by -lisa on 10-10-2007 12:38 PM

[GuenterMueller]

Hi lisa.
Once you have used IMAQ Copy you do not store it for usage in further iterations of your while loop.
Attached is a modification of your VI that uses a shift register to access the copy.
Hope this helps, Guenter

[-lisa]

That's it!!  Thank you very very much Guenter! 

- lisa