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With the ambient use of digital images and the increasing concern on their integrity and originality, consumers are facing an emergent need of authenticating degraded images despite lossy compression and packet loss. In this paper, we propose a scheme to meet this need by incorporating watermarking solution into traditional cryptographic signature scheme to make the digital signatures robust to these image degradations. Due to the unpredictable degradations, the pre-processing and block shuffling techniques are applied onto the image at the signing end to stabilize the feature extracted at the verification end. The proposed approach is compatible with traditional cryptographic signature scheme except that the original image needs to be watermarked in order to guarantee the robustness of its derived digital signature. We demonstrate the effectiveness of this proposed scheme through practical experimental results.

Compression of logo as an image is addressed in logo watermarking, in which a framework of joint Human Vision System (HVS) model and rate allocation theory in the wavelet domain is applied. Under this framework, a novel logo watermarking algorithm using reversible discrete wavelet transform is proposed. Based on multi-level wavelet decomposition of both host and logo images, a well-known HVS model is applied to locate the visually insensitive area in the host for embedding, while the rate allocation theory determines how the logo is compressed and embedded by using the statistical characteristics of the logo. For a given overall embedding distortion, quantization step-sizes of different logo subbands are analytically determined to maximize the fidelity of the extracted logo under the imperceptibility constraint. The adaptive system is thus applicable to different hosts and logos without tuning the parameters manually. It is proved to be robust against various types of attacks and is quite suitable for hardware implementations. Since logo is considered as an image in this new algorithm, the watermarking approach developed can be extended in general to image-in-image embedding.

In print-type steganography and watermarking, visible calibration patterns are arranged around content in which invisible data are embedded, to provide plural feature points for normalization of a scanned image. However, it is clear that conventional visible calibration patterns interfere with the page layout and artwork of original contents. Additionally, visible calibration patterns are not suitable for security services. In this paper, we propose an arrangement of and a detection method for an invisible calibration pattern based on human visual perception. We embed the proposed calibration pattern in an original image by adding a high-frequency component to blue intensity in limited regions. The proposed method protects the page layout and artwork because it is difficult for observers to detect the calibration pattern embedded into an image with a normal background.

Nowadays, digital watermarking is employed for authentication and copyright protection. In this paper, a secure image watermarking scheme based on lifting wavelet transform (LWT) and singular value decomposition (SVD), is proposed. Both LWT and SVD are used as mathematical tools for embedding watermark in the host image. In this work, the watermark is a speech signal which is segmented into shorted portions having the same length. This length is equal to 256 and these different portions constitute the different columns of a speech image. The latter is then embedded into a grayscale or color image (the host image). This procedure is performed in order to insert into an image a confidential data which is in our case a speech signal. But instead of embedding this speech signal directly into the image, we transform it into a matrix and treated it as an image (“a speech image”). Of course, this speech signal transformation permits us to use LWT-2D and SVD to both the host image and the watermark (“a speech image”). The proposed technique is applied to a number of grayscale and color images. The obtained results from peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) computations show the performance of the proposed technique. Experimental evaluation also shows that the proposed scheme is able to withstand a number of attacks such as JPEG compression, mean and median attacks. In our evaluation of the proposed technique, we used another technique of secure image watermarking based on DWT-2D and SVD.

An approach for information storage employs tetrapyrrole macrocycles as charge-storage elements attached to a (semi)conductor in hybrid chips. Anti-counterfeiting measures must cohere with the tiny amounts of such electroactive material and strict constraints on composition in chips; accordingly, the incorporation of typical anti-counterfeiting taggants or microcarriers is precluded. The provenance of the tetrapyrroles can be established through the use of isotopic substitution integral to the macrocycle. The isotopic substitution can be achieved by rational site-specific incorporation or by combinatorial procedures. The formation of a mixture of such macrocycles with various isotopic composition (isotopically unmodified, isotopologues, isotopomers) provides the molecular equivalent of an indelible printed watermark. Resonance Raman spectroscopic examination can reveal the watermark, but not the underlying molecular and isotopic composition; imaging mass spectrometry can reveal the presence of isotopologues but cannot discriminate among isotopomers. Hence, deciphering the code that encrypts the watermark in an attempt at forgery is expected to be prohibitive. A brief overview is provided of strategies for incorporating isotopes in meso-substituted tetrapyrrole macrocycles.

Watermarking technology is widely used in secret communications, in which the security factor is crucial. Existing watermarks protect themselves from being hacked mainly depending on watermarking algorithms. Once hackers obtained the information carriers and figured out the algorithm, secret information embedded in them would be exposed. In this paper, we introduced a Run-length Slotting approach to map information into distributed interrelated images with a hash function. Then we discussed the selection of hash function to avoid information exposure strictly, and gave an algorithm to achieve our goal. Further more, a distributed watermarking model is introduced to improve the security of watermarks.

This paper presents a watermarking algorithm based on fractal coding and wavelet transform. In this method, we adopt images which are self-similar to search for its Iterated Function System(IFS) as the watermark information, considering the robust against geometric transformations of fractal code. A chaos system is utilized to control the position of watermark embedded in the DWT domain, and then append the IFS coefficients to the wavelet decomposition coefficients. The approach proves rather efficient against many kinds of distortions.

With the proliferation of pervasive computing, the frontline of cyberwarfare and digital forensics has been migrated from desktop to more diverse and volatile computational environment, including the cloud and mobile devices. The excessive yet volatile data need to be acquired, transmitted, and analyzed in a timely manner, which makes existing forensic tools and technology inadequate. A sound digital forensics process in the cloud requires stronger mechanisms that enforce authentication and protect data integrity, with the consideration of cloud-specific facets.

In this chapter, we describe CloudForen, a framework that addresses the vulnerabilities of a forensic investigation process. The framework aims at (1) establishing a trustworthy relationship between forensic custodies and (2) transmitting forensic data as stream. To fulfill the first goal, two protocols are proposed to verify the integrity of computer platforms and grant/revoke privileges of custodies, respectively. The protocols harness the effectiveness of Trusted Platform Module (TPM) and Ciphertext-Policy Attribute-based Encryption (CP-ABE), which allow custodies in communication to authenticate the fingerprints of both platforms, as well as the roles of the custodies. To achieve the second goal, forensic data are transmitted between trusted custodies as streaming data, in which a unique fragile watermark is embedded. The advantages of using fragile watermark allows not only data integrity to be verified, but also malicious data manipulation to be localized. In addition, the watermarks are embedded into network packets to minimize communication overhead. Our experimental results demonstrate that CloudForen can achieve good scalability with limited overhead in an Infrastructure as a Service (IaaS) cloud computing environment.