Is there a way to read these in reverse and get the string from the image?
Nope. Thats by design since they were originally meant to identify IPs without revealing the IP.
If the input fields for addresses in the client had a small identicon next to them, and whatever people were manually copying from also had an identicon, it would be a quick way to check for typos in addition to bitcoin's built in checksum. If you are copy/pasting from the same computer, or using a QR scanner, there isn't really a need.