In an exemplary embodiment, image content is rendered to include a digital watermark pattern at an essentially fixed scale, regardless of the size of screen on which the content is displayed. In one particular embodiment, CSS and JavaScript are responsive to the rendering context (which can include screen size, and/or viewer position) to define the geometry of a watermarked texture block, which is tiled to serve as a background of an HTML-defined page. A great variety of other features and arrangements are also detailed.