Get last frame of an image

[A.Salcedo]

Hello to everyone.

First of all thanks a lot for reading this post and being able to help.

I have a code where I take images (snap) with a camera GigE each 0.5sec and I visualize in a Display.

Now I would like to implement a functionality which is that I would like to take last image that camera take and visualize in another display to visualize and measure a simple ROI.

Is there any way or VI which provide me the functionality to take the last image and visualize it in another display?

Thanks a lot!

[udka]

You need to IMAQ create VIs, one for current and other for previous.
-Use shift register and store current image to Previous image once done and so on.

[A.Salcedo]

First of all thanks for replying.

The problem of that is that "Display last image" is refreshing each 0.5 second as well...

I woud llike to press a button and get the last image in the second display and this display does not have to change until I press the button again.

[udka]

Update the image display inside case structure and connect the case selector to button.

[A.Salcedo]

I forgot that I would like to do this in a diferent whiles.

one while for take images each 0.5sec and the other while for take just the last image.

Is that possible?'

Thanks a lot again.

[udka]

Yes, you can send the image to other loop via queue and display in second loop with case structure around image display using button.

Please go through this link for basic structures and how to use it:http://www.ni.com/getting-started/labview-basics/execution-structures

[A.Salcedo]

Could you show me a little code please?

Because I try a lot of things but no works....

[udka]

Sorry i don't have labview now i cannot post any code.
-What you tried so far now?
-For basic structures on case structure and while loop: http://www.ni.com/getting-started/labview-basics/execution-structures
-Shift registers :http://www.ni.com/getting-started/labview-basics/shift-registers#Shift%20Registers
-And you might need Queues to pass images between loops: http://digital.ni.com/public.nsf/allkb/DD7DBD9B10E3E537862565BC006CC2E4

[A.Salcedo]

Thanks a lot.

My question is:

Does queue get bigger and bigger untill I realease it when I push the button?

Or can I push a image on queue, delete image, push again, delete.... So Can queue have just one element?

[udka]

-If you add every image to queue, yes the number of images in queue increases.
-If you don't want every image to be added, then please use case structure and enqueue only that image and display.
-I hope you are familiar with image delete else you might run into another problems.