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We describe a new watermarking system based on the principles of informed coding and informed embedding. This system is capable of embedding 1380 bits of information in images with dimensions 240 x 368 pixels. Experiments on 2000 images indicate the watermarks are robust to significant valumetric distortions, including additive noise, low-pass filtering,(More)
—Considerable progress has been made in the detection of steganographic algorithms based on replacement of the least significant bit (LSB) plane. However, if LSB matching, also known as ±1 embedding, is used, the detection rates are considerably reduced. In particular, since LSB embedding is modeled as an additive noise process, detection is especially poor(More)
Recently Zhang et al described an algorithm for the detection of ±1 LSB steganography based on the statistics of the amplitudes of local extrema in the greylevel histogram. Experimental results demonstrated performance comparable or superior to other state-of-the-art algorithms. In this paper, we describe improvements to this algorithm to (i) reduce the(More)
We propose a new method to detect re-sampled imagery. The method is based on examining the normalized energy density present within windows of varying size in the second derivative of the frequency domain, and exploiting this characteristic to derive a 19-dimensional feature vector that is used to train a SVM classifier. Experimental results are reported on(More)
Informed coding is the practice of representing watermark messages with patterns that are dependent on the cover Works. This requires the use of a dirty-paper code, in which each message is represented by a large number of alternative vectors. Most previous dirty-paper codes are based on lattice codes, in which each code vector, or pattern, is a point in a(More)
— Watermarking digital video material is usually considered as watermarking a sequence of still images. However, such a frame-by-frame approach is very risky since straightforward embedding strategies can result in poor performance in terms of security i.e. against hostile attacks. As examples, two very common video watermarking systems will be presented as(More)
A significant effort has been put in designing watermark-ing algorithms during the last decade. But today, the water-marking community needs some advanced attacks and fair benchmarks in order to compare the performances of different watermarking technologies. Moreover attacks permit to find the weaknesses of an algorithm and consequently trigger further(More)
Unauthorized digital copying is a major concern for multi-media content providers. Since copyright owners lose control over content distribution as soon as data is decrypted or unscrambled, digital watermarking has been introduced as a complementary protection technology. In an effort to anticipate hostile behaviors of adversaries, the research community is(More)