A frequency domain adaptive watermarking algorithm for still colour images

Abstract: In this paper, we propose a blind digital multi- watermarking algorithm for the copyright protection and authentication of medical images. When medical images are transmitted and stored in hospitals, strict security, confidentiality and integrity are required to protect from the illegal distortion and reproduction of the medical information. Medical image watermarking requires extreme care when embedding watermark information in the medical images because the additional information must not affect the image quality as this may cause the wrong diagnosis. The proposed algorithm contains one robust watermark for the ownership of the image and two fragile watermarks for checking the authenticity. The first two watermarks are embedded in the wavelet domain, while the third watermark is embedded in the spatial domain. In the proposed algorithm, the medical image is divided into two regions, called the Region of Interest and Region of Non Interest and all the three watermarks are embedded in the Region of Non-Interest. The new medical watermarking technique offers high peak signal to noise ratio and similarity structure index measure values. The technique was successfully tested on a variety of medical images and the experimental results show that the robust watermark survived many intentional and non intentional attacks, while the fragile watermark is sensitive to any slight tampering on the medical images.

Abstract: This paper deals with a blind hybrid digital watermarking algorithm for the copyright protection and authentication of magnetic resonance tomography images. Medical image watermarking requires extreme care when embedding watermark information in the medical images, to protect the image quality from being violated and to avoid the wrong diagnosis that might occur. The proposed algorithm contains robust watermark for the ownership protection and fragile watermarks for checking the authenticity. In the proposed algorithm, the medical image is divided into two regions, called the Region of Interest and Region of Non-Interest using histogram technique and the watermarks are embedded in both wavelet domain and spatial domain in the Region of Non-Interest Area. The proposed hybrid watermarking technique was successfully tested on a variety of MRI medical images and offerd high peak signal to noise ratio and similarity structure index measure values.

Abstract: This paper presents a reversible invisible watermarking algorithm for the ownership protection and content authentication of medical images. When embedding information in medical images, extreme care is required, to protect the quality of the image to avoid the wrong diagnosis. In the proposed algorithm the patient's unique identity is used for ownership protection and the SHA-256 hash key information is used for content authentication of medical images. The original medical image can be restored after extracting the ownership and authentication watermark information. The new algorithm was successfully tested on a variety of X-ray and MRI medical images and the distortion which is caused by watermarking was assessed by using peak signal to noise ratio, similarity structure index measure and wavelet signal to noise ratio.

Abstract: This paper deals with the development and assessment of a watermarking technique which is suitable for scanned PDF documents. The watermark will serve two purposes. The first one is to protect the copyright ownership. This watermark is a logo which can be extracted even if the document has gone through slight image manipulations. The second one is to authenticate the document. A slight editing in the document will change the second watermark and indicate forgery. The algorithm was tested successfully on a variety of scanned documents and the performances of the algorithm were assessed.

Abstract: This paper discusses a technique used to insert a watermark into scanned colored PDF files. The watermarking aims to protect the copyright ownership and authenticate the PDF documents. A logo has been used as a robust watermark for copyright. The logo will be embedded in the green channel of the file. This watermark can be successfully extracted and it can survive against different attacks. Any manipulations in the PDF file will cause the second fragile watermark to change and indicate forgery. The algorithm was successfully tested on different colored PDF files.

Abstract: Objective methods for assessing perceptual image quality traditionally attempted to quantify the visibility of errors (differences) between a distorted image and a reference image using a variety of known properties of the human visual system. Under the assumption that human visual perception is highly adapted for extracting structural information from a scene, we introduce an alternative complementary framework for quality assessment based on the degradation of structural information. As a specific example of this concept, we develop a structural similarity index and demonstrate its promise through a set of intuitive examples, as well as comparison to both subjective ratings and state-of-the-art objective methods on a database of images compressed with JPEG and JPEG2000. A MATLAB implementation of the proposed algorithm is available online at http://www.cns.nyu.edu//spl sim/lcv/ssim/.

Abstract: Digital watermarking is a key ingredient to copyright protection. It provides a solution to illegal copying of digital material and has many other useful applications such as broadcast monitoring and the recording of electronic transactions. Now, for the first time, there is a book that focuses exclusively on this exciting technology. Digital Watermarking covers the crucial research findings in the field: it explains the principles underlying digital watermarking technologies, describes the requirements that have given rise to them, and discusses the diverse ends to which these technologies are being applied. As a result, additional groundwork is laid for future developments in this field, helping the reader understand and anticipate new approaches and applications.

Abstract: From the Publisher: Steganography, a means by which two or more parties may communicate using "invisible" or "subliminal" communication, and watermarking, a means of hiding copyright data in images, are becoming necessary components of commercial multimedia applications that are subject to illegal use. This new book is the first comprehensive survey of steganography and watermarking and their application to modern communications and multimedia. Handbook of Information Hiding: Steganography and Watermarking helps you understand steganography, the history of this previously neglected element of cryptography, the hurdles of international law on strong cryptographic techniques, a description of possible applications, and a survey of the methods you can use to hide information in modern media. Included in this discussion is an overview of "steganalysis," methods which can be used to break steganographic communication. This comprehensive resource also includes an introduction to and survey of watermarking methods, and discusses this method's similarities and differences to steganography. You gain a working knowledge of watermarking's pros and cons, and you learn the legal implications of watermarking and copyright issues on the Internet.

Abstract: Summary form only given. The ability to represent audio and video digitally and its vast popularity poses enormous challenges in protection against unauthorized use, copy and distribution in open, highly uncontrolled Internet environment. Digital watermarking, a technology for insertion of imperceptible information into multimedia content offers a solution for authentication and suitable action thereof. This is a rapidly maturing technology. Initiatives within the industry are ongoing for various forms of multimedia. Technology alone is unlikely to address all the copy protection issues. Business models and legal support also play an important role in tackling them.

Abstract: Most colour watermarking methods are realised by modifying the image luminance or by processing each component of colour space separately This paper presents a novel and robust colour watermarking approach for applications in copy protection and digital archives The proposed scheme considers chrominance information that can be utilised at information embedding This work presents an approach for hiding the watermark into DC components of the colour image directly in the spatial domain, followed by a saturation adjustment technique performed in RGB space The merit of the proposed approach is that it not only provides promising watermarking performance but also is computationally efficient Experimental results demonstrate that this scheme successfully makes the watermark perceptually invisible and robust to image processing operations such as general image processing operations (JPEG2000, JPEG-loss compression, lowpass filtering, and medium filtering), image scaling and image cropping