Hardware Implementations of Image/Video Watermarking Algorithms

Digital watermarking is a process in which a secondary pattern or signature, called a watermark, is hidden into a digital media (e.g., image and video) such that it can be detected or extracted later for different intentions. Digital watermarking has many applications including copyright protection, authentication, tamper detection, and embedding of electronic patient records in medical images. Various software implementations of digital watermarking algorithms can be built. While software implementations can address digital watermarking in off-line applications, they cannot meet the requirements of many applications. For example, in consumer electronic devices, a software solution would be very expensive. This has motivated the development of hardware implementations of digital watermarking. In this chapter, the authors present a detailed survey of existing hardware implementations of image and video watermarking algorithms. Fundamental design issues are discussed and special techniques exploited to enhance efficiency are identified. Future outlooks are also presented to address the challenges of hardware architecture design for image and video watermarking.

From Watermarking to In-Band Enrichment

Fostered by the emerging Knowledge Society, the enriched media is nowadays a very challenging research topic, be it considered either from academic or from industrial perspectives. In its largest acceptation, enriched media refers to all possible associations established between some original data (video, audio, 3D, …) and some metadata (textual, audio, video, executable codes, …). Such a new content may be further exploited for various applications, like interactive HDTV, computer games, or data mining, for instance. This chapter is meant to bring into evidence the role watermarking techniques may play in this new applicative field. Following the watermarking philosophy, the in-band enrichment supposed that the enrichment data are inserted into the very data to be enriched. Thus, three main advantages are ensured: backward compatibility, format coherence, and virtually no network overhead. The discussion is structured on both theoretical aspects (the accurate evaluation of the watermarking capacity in several real-life scenarios) and on applications developed under the framework of the R&D contracts conducted at the ARTEMIS Department, Institut TELECOM.

Spread Spectrum Watermarking

Spread spectrum (SS) watermarking has proven to be efficient, robust and cryptographically secure. Each bit of watermark information is embedded over wide spectrum of the host signal based on spectrum spreading concept of SS modulation in digital communication and can easily be integrated with many existing data transmission scheme. This has made SS watermarking method more attractive during recent times for many non-conventional applications such as broadcast monitoring, security in communication, authentication and blind assessment of quality of services (QoS) for multimedia signals in mobile radio network. These applications essentially demand development of low cost algorithms so that they can be implemented on real time system through hardware realization. Hardware realization offers advantages over software realization in terms of less area, low execution time, low power, real-time performance, high reliability and also ease of integration with existing consumer electronics devices. This chapter first presents a brief review on hardware implementation of digital watermarking algorithms, followed by development of hardware architecture for spatial domain and fast Walsh transform (FWT) domain SS watermark system design using field programmable gate array (FPGA). A brief sketch on hardware implementation for biorthogonal wavelet based Hilbert transform is also shown that may be extended to design SS watermarking based on the concept of two previous architectures. Few challenges for hardware design of watermarking algorithms are then mentioned with an objective to give an idea how to develop watermarking algorithms so that it can be implemented on hardware. The chapter ends with few open research problems on hardware architecture as scope of future research work.

Copyright Protection in the Distribution of Multimedia Digital Objects in Internet

This chapter shows the most significant approaches developed so far for the distribution of digital contents with copyright protection, highlighting their most interesting features. These proposals may be classified into two categories: on the one hand systems that try to prevent unauthorized uses of the contents, and on the other hand systems whose purpose is to detect unauthorized uses of the contents and to identify involved offenders. This chapter is focused on the systems that fit in the second of these strategies, most of which are based on the use of watermarking techniques. However, watermarks cannot provide a suitable answer to this issue by themselves, but they must be framed into more complex systems, involving the participation of different entities and the use of well defined protocols which establish the exchange of data and contents among these entities. It is important to point out that cryptography is also a key element in all of these systems and protocols.

Techniques for Multiple Watermarking

The watermarking problem is relatively well understood in the single watermark case, but it lacks theoretical foundation in the multiple watermarks case. The goal of this chapter is to provide important technical insights as well as intuitive and well developed discussions onto how multiple watermarks can be embedded efficiently into the same host signal. The authors adopt communication and information theoretic inclinations, and they argue that this problem has tight relationship to conventional multiuser information theory. Then they show that by virtue of this tight relationship design and optimization of algorithms for multiple watermarking applications can greatly benefit from recent advances and new findings in multiuser information theory.

Data Secrecy

This chapter describes a framework for image hiding that exploits spectral properties of the Fourier magnitude and phase of natural images. The theory is that as long as the Fourier phase of an image is maintained intact, the overall appearance of an image remains specious if the Fourier magnitude of the image is slightly modified. This hypothesis leads to a data hiding technique that promises high fidelity, capacity, security, and robustness to tampering. Experimental results are presented throughout the chapter that demonstrate the effectiveness of this approach.

Optimization in Digital Watermarking Techniques

Digital watermarking (DWM) becomes a multidisciplinary research area involving theory of communications, signal processing, multimedia coding, information theory, cryptography, computer science and game theory etc. This chapter looks digital watermarking as an optimization problem from different combination of these areas. The goal is to resolve the conflicting requirements of different parameters and properties of digital watermarking. The chapter also presents a review of recent advances in the state-of-the-art algorithms for optimized watermarking techniques. Optimized watermarking methods are then discussed from the rigorous mathematical analysis to theoretical derivations of algorithms with the aid of soft computing techniques. The design and implementation of optimized watermarking methods for the image, video and sound signals are discussed in the context of various diverse applications. Finally, the scope of future research in this area is highlighted.

A Unified Approach Towards Multimedia Watermarking

The tremendous advancement of digital technology has increased the ease with which digital multimedia signals (image, video, audio) are stored, transmitted, and reproduced. Consequently, the content providers and owners are faced with problems of protection against copyright violation and other forms of abuse to their digital property. Digital watermarking has been proposed in the last decade as a solution to prevent illegal and malicious copying and distribution of digital media by embedding an unnoticeable information into the media content. This chapter describes three imperceptible and robust watermarking algorithms for different types of multimedia objects (image, video, audio). The three algorithms are based on cascading two powerful mathematical transforms; the Discrete Wavelet Transform (DWT), and the Singular Value Decomposition (SVD). The two transforms are different, and thus provide complementary levels of robustness against the same attack. In the proposed dual-transform algorithms, the watermark bits are not embedded directly on the wavelet coefficients, but rather on the elements of singular values of the DWT sub-bands of the multimedia object. Effectiveness of the proposed algorithms is demonstrated through extensive experimentation.

Geometric Distortions-Invariant Digital Watermarking Using Scale-Invariant Feature Transform and Discrete Orthogonal Image Moments

Many proposed digital image watermarking techniques are sensitive to geometric attacks, such as rotation, scaling, translation, or their composites. Geometric distortions, even by slight amounts, can inevitably damage the watermark and/or disable the capability of the watermark detector to reliably perform its function. In this chapter, the authors exploit the invariant image features to design geometric distortions-invariant watermarking system, and present two watermarking techniques. First technique utilizes the bounding box scale-invariant feature transform and discrete orthogonal Hahn moments to embed the watermark into the selective image patches, and the second technique uses only the Hahn moments to globally embed watermark into the whole image. First technique is non-blind and uses the original image during detection. While exhibiting excellent resistance against different geometric distortions, this technique also has fairly good resistance to image cropping like attacks. However, this technique exhibits a reduced data payload. The second technique is designed to be blind and the watermark is blindly extracted using the independent component analysis. For this technique an improved data payload is achieved but with a little compromise on resistance against cropping like attacks. The implementations are supported with thorough discussions and the experimental results prove and demonstrate the effectiveness of the proposed schemes against several kinds of geometric attacks.

Color in Image Watermarking

This chapter summarizes the state-of-the-art color techniques used in the emerging field of image watermarking. It is now well understood that a color approach is required when it comes to deal with security, steganography and watermarking applications of multimedia contents. Indeed, consumers and business expectations are focused on the protection of their contents, which are here color images and videos. In the past few years, several gray-level image watermarking schemes have been proposed but their application to color image is often inadequate since they usually work with the luminance or with individual color channel. Unfortunately, color cannot be considered as a simple RGB decomposition and all of its intrinsic information must be integrated in the watermarking process. Therefore, it is the chapter objective to present, first, the major difficulties associated with the treatment of color images, and second, the state-of-the-art methods used in the field of color image watermarking.