Joint Halftoning and Visible Watermarking

Visible watermarking is a technique to embed a perceivable image in a host image for copyright protection. Existing visible watermarking methods mainly concern about continuous-tone images, however, few attention is paid to two-tone images. This paper proposes a visible watermarking scheme for halftone images called joint halftoning and visible watermarking (JHVW). JHVW embeds data during halftoning, namely the host image is a continuous-tone image and the watermarked image is a halftone image. The watermarked halftone image contains recognizable but unobtrusive watermark information, and the details of the host image still be maintained. Our schemes can be used in applications such as in advertisement or as a restriction.