The science of hiding Image(s) or information within other image(s) or information. In security documents, the hidden image or information is typically revealed with the aid of a decoder lens, scanning device, or decoding software in a handheld or desktop device.

Tactile Code

An image that has been embossed, debossed, or stamped into a surface of a substrate but has not been printed or foil stamped. Creates a raised impression used as an authenticator.