Hi,
There are a couple ways you can do this, they normally require some code writing from you:
- Magic wand can help you draw a contour however your area of contouring needs to be clearly defined. You can find an example for this in the NI Example Finder >> Toolkits & Modules>> Vision>> Functions>> Magic Wand Example.vi
- You can write some code that performs a similar type of action, please see the attached. You can combine functions such as edge detection with filtering...
I also found this example; I thought you might find it interesting: http://zone.ni.com/devzone/cda/tut/p/id/3169
Again for superimposing the two images there is no VI that is specifically designed to do this for you however you can make an algorithm that does this. For instance you can convert the images to arrays and multiply them together to identify the intensity of the pixel.
Hope this helps.
Regards,
Mahdieh G
Applications Engineer
National Instruments UK&Ireland