Have you looked for LabVIEW Examples that deal with this? Have you written any code for which you need help? Are you looking for an experienced LabVIEW developer to do this for you?
How to find the defect or crack using edge detection .
First you should try with vision assistant tool, it it's work with several images where you've been taken defect & good images. Then you able to convert in to LabVIEW code.
Meanwhile find this link,