How much data can be hidden in an image?
QR codes use black and white, and the largest 177 square QR can store about 3000 bytes.
But if more of the color range is used, much more data can be stored!
Steganography is the art and science of embedding and hiding information within a medium in plain sight. It’s related to cryptography and is just about as old. For example, it was used by the Ancient Greeks to hide information about troop movements by tattooing the information on someone’s head and then letting the person grow out their hair!
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