A digital watermarking system and method are disclosed. In one respect, the disclosed digital watermarking includes generating an extracted signal by applying a watermark extractor to an original image, generating a mixed signal by mixing the first signal with a periodic watermark signal using a local weighting factor for the periodic watermark signal that attenuates a strength of the watermark signal in proportion to a pixel luminance level, and replacing the extracted signal in the original image with the mixed signal to generate a marked image, wherein the watermark signal is extractable from the marked image using the watermark extractor.