The presently claimed invention relates generally to data encoding and steganography. One combination recites a method of encoding data representing color imagery with an auxiliary signal. The method includes: providing a set of encoding values for a data sample; determining a color characteristic associated the data sample based on associated color values; and selectively scaling color values in the data sample based on the color characteristic to encode at least a portion of the auxiliary signal in the data representing color imagery. Of course, other combinations are provided as well.