It just so happens that I've been working on a VI to identify points in an image and output their co-ordinates.
You'll need the IMAQ Vision module for LabVIEW to make it work.
If your data is a set of discrete points on a white background (without grids) then this will work. It won't work if your graph is a continuous line, but you may be able to do something similar using "IMAQ local threshold".
Doing some math on the co-ordinates of points in the image should give you the graph values, but you might want to play around with the code a bit since I made this for a completely different purpose.
