>>Colby concedes that there are some instances where scanned images produce multiple layers. “It’s a program called OCR that converts text in the images into computer readable text,” he said. “But, it would never work on signatures. So, the fact that the signatures have been edited discounts the possibility of it being OCR.” <<
From the article
I hope that answers your question about what OCR software is capable of doing these days. In fact, it was doing that before I retired!
They have machinery in mail processing centers that can detect anthrax bacteria. It can also detect thousands of chemicals, and millions of other viruses and bacteria.
The big one is explosives though ~ always some nutcase out there who thinks he can slip a letter bomb into the system. Does not happen!