Image Watermarking Using Visual Cryptography

Definition:A new class of digital watermarking techniques is based on visual cryptography.

Recent works have introduced a new class of digital watermarking schemes which employ visual cryptography (VC) concepts to secure watermarked content [1], [2], [3]. In addition, VC-based watermarking may be used to robustify recognition of an extracted watermark from images which have been subjected to attacks [2], [3]. For example, in the approach shown in Figure 1, instead of embedding a binary logo directly to the host image, a VC-based watermarking scheme first encrypts the binary logo into two noise-like binary shares. One of the two generated shares can be viewed as a private watermark share and is kept by the owner. The other share represents a public watermark share and is being embedded to the host image using a conventional watermarking technique which operates either in the spatial or frequency domain of the host image [2], [3].

Figure 1.

Visual cryptography based digital watermarking.