The watermarking of digital images, audio, video and multimedia products in general has been proposed for resolving copyright ownership and verifying originality of content. This paper studies the contribution of watermarking for developing protection schemes. A general watermarking framework (GWF) is studied and the fundamental demands are listed. The watermarking algorithms, namely watermark generation, embedding and detection, are analyzed and necessary conditions for a reliable and efficient protection are stated. Although the GWF satisfies the majority of requirements for copyright protection and content verification, there are unsolved problems inside a pure watermarking framework. Particular solutions, based on product registration and related network services, are suggested to overcome such problems. 1 1 Introduction The digital form of photographs, paintings, speech, music, video etc. became very popular in the last decade. Digital facilities for creating, processi...

The growth of high speed computer networks and that of Internet, in particular, has explored means of new business, scientific, entertainment, and social opportunities. Ironically, the cause for the growth is also of the apprehension - use of digital formatted data. Digital media offer several distinct advantages over analog media, such as high quality, easy editing, high fidelity copying. The ease by which a digital information can be duplicated and distributed has led to the need for effective copyright protection tools. Various software products have been recently introduced in attempt to address these growing concerns. It is done by hidding data (information) within digital audio, images and video files. One way such data hidding is digital signature, copyright label or digital watermark, that completely characterizes the person who applies it and, therefore, marks it as being his intellectual property. Digital Watermarking is the process that embeds data called a watermark into a multimedia object such that watermark can be detected or extracted later to make an asertion about the object. Watermarking is either "visible" or "invisible". Although visible and invisible are visual terms watermarking is not limited to images, it can also be used to protect other types of multimedia object. This work is a tutorial review of the digital watermarking techniques appreared in the literature.

Many watermarking algorithms have been proposed and studied for their robustness and other properties. But, there has been little eort is analyzing these algorithms for their vulnerability against detection by an adversary. As a general philosophy for robust watermarking the host signal and the watermarked signal are well separated in a statistical distance sense. This very nature can be exploited by an adversary to easily detect the watermark and perhaps remove it. We argue that the ability of a watermark to avoid detection by an adversary is a key factor that needs great attention. In this paper, we propose a method for watermark analysis based on a distributed detection framework that can be used by an adversary. The proposed framework can be used by the adversary to study signals for the presence/absence of watermarks. We choose a particular spatial domain image watermarking algorithm and explain how the proposed framework can be applied to detect the watermark with very little knowledge about the watermark insertion procedure. The false alarm probability can be optimally traded-o with the probability of detection using the receiver operating characteristic function.

A digital watermark is a visible, or preferably invisible, identification code that is permanently embedded in some digital data to prove owner authentication and provide protection of that document. In this paper we utilize a watermark generation technique based on the use of chaotic functions and the motivation for using these functions is presented. The technique used for watermark embedding is also described, together with a watermark detection scheme based on an optical Matched Filter correlator. We provide results of optical simulations of the watermark detection scheme and show that correlation-based detection is an excellent method for detecting chaotically-generated watermarks embedded in the Fourier domain using multiplicative embedding. We also show that it is possible to detect chaotically-generated watermarks in images that have been subjected to noise.

Abstract. This paper addresses feature-based image watermarking methods for digital contents. Most previous watermarking algorithms suffer from geometric distortion attacks that desynchronize the location of the inserted watermark. In order to synchronize the watermark location, watermark synchronization should be performed. One solution for watermark synchronization is to use image features. This paper describes a feature-based watermarking method based on scale-invariant keypoints. We extract feature points from the scale-invariant keypoint extractor and then decompose feature points into a set of disjoint triangles. These triangles are watermarked by an additive spread-spectrum method on the spatial domain. We perform an intensive simulation in comparison with other feature-based watermarking methods using 100 test images. Results show that the proposed method is considerably robust against both geometric distortion attacks and signal processing attacks listed in Stirmark 3.1. 1

This paper proposes a novel content-based image watermarking method based on invariant regions of an image. The invariant regions are self-adaptive image patches that deform with geometric transformations. Three different invariant-region detection methods based on the scale-space representation of an image were considered for watermarking. At each invariant region, the watermark is embedded after geometric normalization according to the shape of the region. By binding watermarking with invariant regions, resilience against geometric transformations can be readily obtained. Experimental results show that the proposed method is robust against various image processing steps, including geometric transformations, cropping, filtering, and JPEG compression.

This paper develops a digital watermarking methodology for 3-D graphical objects defined by polygonal meshes. In watermarking or fingerprinting the aim is to embed a code in a given media without producing identifiable changes to it. One should be able to retrieve the embedded information even after the shape had suffered various modifications. Two blind watermarking techniques applying perturbations onto the local geometry for selected vertices are described in this paper. The proposed methods produce localized changes of vertex locations that do not alter the mesh topology. A study of the effects caused by vertex location modification is provided for a general class of surfaces. The robustness of the proposed algorithms is tested at noise perturbation and object cropping. 1

The visual information provided by 2D images is typically static and so the entire content of an image is shown at once. When image components are now annotated to communicate the image’s content more clearly, the actual information of the image is partially hidden. However, by hiding an image’s annotations by default, the image can be turned into an interactive medium for which a user can demand the descriptive information at will. We suggest employing digital watermarking techniques to store auxiliary information directly in the regions the information is associated with, a procedure that we call Illustration Watermarking. That way, the additional information becomes part of the image but it is not permanently displayed. In this paper, we describe three illustration watermarking techniques. To analyze and compare these techniques and to determine the maximum amount of data which can be invisibly embedded per pixel, we conducted a user study. In this study, participants searched for coded regions in images of different types and with different amounts of data encoded. One of our results is that under normal viewing conditions at least 5 bits/pixel can be modified without perceivably changing the image. Finally, we present several application fields in which our proposed technique can be applied to enhance the image’s communication of its information. 1

Digital Watermarking is one of the most prominent technique used for protection of ownership rights of digital media which is text, audio, video or image. For providing more security to the information and to enhance the hiding capacity of an image and avoid abrupt changes in image edge areas, as well as to achieve better quality of the stegoimage, a novel image data hiding technique by Wavelet Watermarking and frequency domain is proposed in this paper. The paper focuses on Image Adaptive watermarking methods in the Discrete Wavelet Transform Domain and frequency domain since they yield better results regarding robustness and transparency than other watermarking schemes. In this paper the technique is proposed to hide text data into noisy region of a digital image. The Discrete Wavelet Transform Domain and frequency domain dual adaptive watermarking algorithm which will be used for the novel application for watermarking. It helps, for providing more security to the information and result show our algorithm is best for data hiding in image. Keywords- Wavelet Watermarking, frequency domain, PSNR, Image steganography, Image encrypton.