Combining semacodes and steganography?

I imagine part of the robustness of a semacode to damage/dirt/obscuration is the high contrast between the two states of any "cell". The reader can still make a good guess as to the actual state, even with some distortion.

That sort of contrast is not available in a photographic image, and is the very reason why steganography works - the lsb bit-flipping has almost no visual effect on the image itself, while digital fidelity ensures that a non-visual system can still very accurately read the embedded data.

As the two applications are sort of at opposite ends of the analog/digital spectrum (semacodes are all about being decipherable by analog (visual) processing but are on paper, not digital; steganography is all about the bits in the file and cares nothing for the analog representation, whether light or sound or something else), I imagine a combination of the two will extremely difficult, if not impossible.

Essentially what you're thinking of is being able to steganographically embed something in an image, print the image, make a colour photocopy of it, scan it in, and still be able to extract the embedded data.

I'm afraid I can't help, but if anyone achieves this, I'll be DAMN impressed! :)