While hieroglyphic cryptography is a thing (as is BTW "sportive orthography" in Ancient Egyptian), this is not it. I am all for acknowledging that Ancient Egypt

While hieroglyphic cryptography is a thing (as is BTW "sportive orthography" in Ancient Egyptian), this is not it. I am all for acknowledging that Ancient Egyptian art is often merging writing and depiction in a way that escapes the unprepared who would point to a prominent figure in a grave wall decoration and say 'this is a picture', then point to some hieroglyphs and say 'that is writing'. It's in principle not wrong but misses the point that frequently the choice of hieroglyphs, their orientation and variations in orthography correspond to details of the depicted subject, while the pictures can often be read out, either by describing the participants and their actions, or by naming the parts. As for the latter, there's a statue of "Ramesses II (Dyn XIX) as a Child"[1] which shows Horus as a falcon with the sun (rꜥ) on his breast, a child (ms) beneath it, in his hand a sedge plant (sw). Naming the parts—sun, child, sedge—in this order gives rꜥmssw, vocalized raꜥmissaw, roughly maybe approximately [raʕ'missaw], in any event the very name of Ramesses, meaning "He is / was born / brought forth by Ra / the Sun". Note that you'll have to choose to omit ḥr "Horus" although the falcon dominates the sculpture, and that the sedge does not represent a plant but, by virtue of sounding like it, the 3rd person suffix sw "he", so there's some guesswork involved. All said, it's a fine example of a "rebus". Neither rebus reading nor pictorial description are commonly classified as cryptographic orthography in Egyptology. The statue demonstrates nicely how acutely aware of their language, their artistic traditions and their writing Egyptian artists were. When we look at the depiction of Pharaoh and Amun on the obelisk as explained by Olette-Pelletier, however, we hardly see any of this. Yes, an arm with an offering on the palm of the hand was often used to write dy "to give", but usually those offerings are triangular bread loaves, not round nw vessels. Yes, the hieroglyph for "ḥtp" looks like a flat rectangle but, again, with a bread offering on it which is missing from the flat rectangle that pharaoh is kneeling on. I really wonder what the fuzz is about; clearly it's a picture of the king giving offering to the god, and all he does is read out the picture. This is something that you can do with a lot of Egyptian art: there's the king, you know him by the distinctive crown, and there's Amun, which you know again by his distinctive headdress sporting two long feathers. The king is kneeling because he's offering, and he has his arms stretched out presenting stuff because he's, well, giving. The king is giving things to the god. What part of that was not known before, what part of that is cryptographic? [1]: https://en.wikipedia.org/wiki/File:Ramesses_II_as_child.jpg https://en.wikipedia.org/wiki/File:Ramesses_II_as_child.jpg