Intra-Block Max-Min Algorithm for Embedding Robust Digital Watermark into Images

We present a new DCT-based block max-min algorithm for digital watermark embedding in images. Our algorithm uses intra-block bordering upon pixels relations to generate the watermarked image. The features of our method to embed the watermark are: (1) the watermark is perceptually invisible; (2) low loss of relevant information of the original image; (3) the watermark can be read only by using a secret key, (4) the watermark is robust against translation and area cropping; and (5) retrieval of embedded watermark does not need the original image. We describe the algorithm framework and its performance against translation and area cropping with experiments.