Handling IMAQ Images in the TestStand Opeator Interface

Question

I'm modifying the LabVIEW Operator Interface to display images from IMAQ VIs on the front panel. I've got it to work a number of ways, but never if I compile the interface into an executable.
I've tried using the "IMAQ Image Cluter to Image Dataype" and "IMAQ Image Datatype to Image Cluster" vi's to store and pass references to the Operator Inteface. It works in development mode but not when built. I understand this won't work as the reference is local to the adapter you are using so I abandoned that.
I've tried storing the Image into a global VI and then reading that global VI in the interface for display. I've made sure to call the Global VI dynamically in the operator interface so I'm using the same VI and not one compiled into the executable. It works in development mode but not compiled. Don't know why.
Another method I tried was to use the "Flatten To String" and "Unflatten From String" functions to store the image in a local string (as a binary string) in the sequence. I then tried accessing the local with the "ProperyObject" Method "GetValString" in the Operator Interface VI. When I try this I get an error and the development system shuts down. I know I'm access the local correctly as I have accessed other locals from the sequence in this manner.
Any ideas why one or both of the last two methods are not working for me? Is there any other methods that would work? How about sending the image to a common dll? Can you store an image or image reference in a dll so any platform could access it?
Thanks,
Dave

Answer 1

Thanks for the tip about trying another data type. I tried an numeric array and it did not work as well. But now I could see what is happening. When the GetValString reads the local it does not interpret the escape code '\'. i.e. if the string contains '\00' it ends up as '5C 30 30'. The Unflatten From String vi is expecting hex 00 and an error occures.
I wrote a crude VI to look for the escape code and convert what follows to pure hex. It first converts the string to byte array, interprets each byte, creates a new hex array then converts it back to a string. The good news is that it works for numeric arrays, and I was able to read the array values in the Operator Interface by reading the flattened data from the sequence. However, when I applied the VI to the Image Flattened data, the array was 2,295,879 elements long and my VI was way too slow to convert the whote image.
Is there a fast way of converting the string to pure hex values?
Don't know why my VI didn't show up. I'm now trying to attach an image of the block diagram.
Attachments:
FlattendImagefromSequence.jpg ‏46 KB