If the digital image is stored on a SD card, there are programs that can find it and restore it. Actually, the file has a "?" put in front of the file name. That makes it disappear from the listing and available to be written over by another file. So the "unerase" program looks for those files and allows you to restore it (them, if multiple files). If your SD card goes corrupt, these "unerase" program can help. They are called "recovery programs", many are free.