The existence of perceptual redundancy of many media carriers such as image and video allows for invisible embedding of an information sequence. Its applications include so-called watermarking and data hiding. The media carrier can be modeled as a communication channel, where noise comes from manipulation of the carrier. To maximize the robustness of the embedded data against the noise, coded modulation is used to encode the information sequence.
Michael T. Orchard,
"Coding and modulation in watermarking and data hiding", Proc. SPIE 3657, Security and Watermarking of Multimedia Contents, (9 April 1999); doi: 10.1117/12.344701; https://doi.org/10.1117/12.344701