This patent document relates generally to steganography and digital watermarking. One claim recites a method comprising: receiving data representing image or video, in which the data comprises first data corresponding to first color data, second data corresponding to second color data and third data corresponding to third color data, the image or video to host auxiliary information; weighting the first data, the second data and the third data according to at least the following two factors: i) a color direction biased toward an expected embedding direction; and ii) expected image or video distortion introduced to the first data, the second data or the third data through image capture or signal processing; determining, from weighted first data, weighted second data and weighted third data, changes in an image or video attribute; and transforming the data representing image or video with the changes, in which the auxiliary information is conveyed through the changes. Of course, other claims are provided too.