Towards second generation watermarking schemes
The digital watermarking schemes of today use pixels (samples in the case of audio), frequency or other transform coefficients to embed the information. The drawback of such schemes is that the watermark is not embedded in the perceptually significant portions of the data. We refer to such techniques as first generation watermarking schemes. In this paper we introduce the concept of second generation watermarking schemes which, unlike first generation watermarking schemes, employ the notion of data features. We propose a scheme based on point features in images using a scale interaction technique based on 2D continuous wavelets. The features are used to compute a Voronoi partition of the image. The watermark is embedded in each segment using spread spectrum watermarking. In the recovery process the same features are detected, and again used to partition the image. Then the watermark is extracted from each segment separately.