The present invention relate generally to digital watermarking. One claim recites a method including: obtaining first data representing a first chrominance channel of a color image or video, where the first data comprises a watermark signal embedded therein; obtaining second data representing a second chrominance channel of the color image or video, the second data comprising the watermark signal embedded therein but with a signal polarity that is inversely related to the polarity of the watermark signal in the first data; combining the second data with the first data in a manner that reduces image or video interference relative to the watermark signal, said act of combining yielding third data; using at least a processor or electronic processing circuitry, processing the third data to obtain the watermark signal; and once obtained, providing information associated with the watermark signal. Of course, additional combinations and claims are provided as well.