Watermark detection in an image or the like is optimized by exploiting
the innate biases in the image to emphasize the watermark signal. The watermark
signal can be trial-located with different origins in the image to find one that
yields improved results. Similarly, the image can be processed (e.g., by changing
resolution, rotation, or compression) so as to change the innate biases to better
reinforce the watermark signal. Compression of an image can be done in accordance
with a desired watermark signal, with the compressor deciding which image components
to retain and which to discard based, in part, on a watermark signal that is to
be encoded (or maintained) in the image.
