Digital image watermarking has gained a great interest in the last decade among researchers. Having such a great community which provide a continuously growing list of proposed algorithms, it is rapidly finding solutions to its problems. However, still we are far away from being successful. Therefore, more and more people are entering the field to make the watermarking idea useful and reliable for digital world. Of these various watermarking algorithms, some outperform others in terms of basic watermarking requirements like robustness, invisibility, processing cost, etc. In this thesis, we study the performances of different watermarking algorithms in terms of robustness. Algorithms are chosen to be representatives of different categories such as spatial and transform domain. We evaluate the performance of a selected set of 9 different methods from the watermarking literature against again a selected set of attacks and distortions and try to figure out the properties of the methods that make them vulnerable or invulnerable against these attacks.

We present an Intellectual Property (IP) protection technique for sequential circuits driven by embedding a decomposed signature into a Finite State Machine (FSM) through the manipulation of the arbitrary state encoding of the unprotected FSM. This technique is composed of three steps: (a) transforming the signature into a watermark graph, (b) embedding watermark graphs into the original FSM's State Transition Graph (STG) and (c) generating models for verification and extraction. In the watermark construction process watermark graphs are generated from signatures. The proposed methods for watermark construction are: (1) BSD, (2) FSD, and (3) HSD. The HSD method is shown to be advantageous for all signatures while providing sparse watermark FSMs with complexity O(n^2). The embedding process is related to the sub-graph matching problem. Due to the computational complexity of the matching problem, attempts to reverse engineer or remove the constructed watermark from the protected FSM, with only finite resources and time, are shown to be infeasible. The proposed embedding solutions are: (1) Brute Force and (2) Greedy Heuristic. The greedy heuristic has a computational complexity of O(n log n), where n is the number of states in the watermark graph. The greedy heuristic showed improvements for three of the six encoding schemes used in experimental results. Model generation and verification utilizes design automation techniques for generating multiple representations of the original, watermark, and watermarked FSMs. Analysis of the security provided by this method shows that a variety of attacks on the watermark and system including: (1) data-mining hidden functionality, (2) preimage, (3) secondary preimage, and (4) collision, can be shown to be computationally infeasible. Experimental results for the ten largest IWLS 93 benchmarks that the proposed watermarking technique is a secure, yet flexible, technique for protecting sequential circuit based IP cores.

We present a method of mitigating theft of sequential circuit Intellectual Property hardware designs through means of watermarking. Hardware watermarking can be performed by selectively embedding a watermark in the state encoding of the Finite State Machine. This form of watermarking can be achieved by matching a directed graph representation of the watermark with a sub-graph in state transition graph representation of the FSM. We experiment with three approaches: a brute force method that provides a proof of concept, a greedy algorithm that provides excellent runtime with a drawback of sub-optimal results, and finally a simulated annealing method that provides near optimal solutions with runtimes that meet our performance goals. The simulated annealing approach when applied on a ten benchmarks chosen from IWLS 93 benchmark suite, provides watermarking results with edge overhead of less than 6% on average with runtimes not exceeding five minutes.

Safeguarding creative content in a digital form has become increasingly difficult. It is progressively easier to copy, modify and redistribute digital media, which causes great declines in business profits. For example, the International Federation of the Phonographic Industry estimates that in 2001 the worldwide sales of pirated music CDs were 475 million US dollars. While a large amount of time and money is committed to creating intellectual property, legal means have not proven to be sufficient for the protection of this property. Digital watermarking is a steganographic technique that has been proposed as a possible solution to this problem. A digital watermark hides embedded information about the origin, status, owner and/or destination of the data, often without the knowledge of the viewer or user. This dissertation examines a technique for digital watermarking which utilizes properties of the Discrete Wavelet Transform (DWT). Research has been done in this field, but which wavelet family is superior is not adequately addressed. This dissertation studies the influence of the wavelet family when using a blind, nonvisible watermark in digital media. The digital watermarking algorithm uses a database of multiple images with diverse properties. Various watermarks are embedded. Eight different families of wavelets with dissimilar properties are compared. How effective is each wavelet? To objectively measure the success of the algorithm, the influence of the mother wavelet, the imperceptibility of the embedded watermark and the readability of the extracted watermark, the Peak Signal-to-Noise Ratio and the Image Quality Index for each wavelet family and image are obtained. Two common categories of digital watermarking attacks are removing the watermark and rendering the watermark undetectable. To simulate and examine the effect of attacks on the images, noise is added to the image data. Also, to test the effect of reducing an image in size, each image containing the embedded watermark is compressed. The dissertation asks the questions: “Is the wavelet family chosen to implement the algorithm for a blind, nonvisible watermark in digital images of consequence? If so, which family is superior?” This dissertation conclusively shows that the Haar transform is the best for blind, non-visible digital watermarking.

In this thesis, we address the problem of digital intellectual property (IP) protection for the field programmable gate array (FPGA) designs. Substantial time and effort is required to the design complex circuits; thus, it makes sense to re-use these designs. An IP developer can sell his design to the companies and collect royalty. However, he needs to protect his work from security breach and piracy. The legal means of IP protection such as patents and license agreements are a deterrent to illegal IP circulation, but they are insufficient to detect an IP protection breach. Watermarking provides a means to identify the owner of a design. Firstly, we propose a watermarking technique that modifies the routing of an FPGA design to make it a function of the signature text. This watermarking technique is a type of constraint-based watermarking technique where we add a signature-based term to the routing cost function. Secondly, we need a method to verify the existence of the watermark in the design. To address this we propose a digital signature generation technique. This technique uses the switch state (ON/OFF) of certain switches on the routing to uniquely identify a design. Our results show less than 10% speed overhead for a minimum channel width routing. Increasing the channel width by unit length, we could watermark the design with a zero speed overhead. The increase in the wire length is negative for majority of the circuits. Our watermarking technique can be integrated into the current routing algorithm since it does not require an additional step for embedding the watermark. The overall design effort for routing a watermarked design is equivalent to that of routing a non-watermarked design.

The multimedia revolution has made a strong impact on our society. The explosive growth of the Internet, the access to this digital information generates new opportunities and challenges. The ease of editing and duplication in digital domain created the concern of copyright protection for content providers. Various schemes to embed secondary data in the digital media are investigated to preserve copyright and to discourage unauthorized duplication: where digital watermarking is a viable solution. This thesis proposes a novel invisible watermarking scheme: a discrete cosine transform (DCT) domain based watermark embedding and blind extraction algorithm for copyright protection of the color images. Testing of the proposed watermarking scheme's robustness and security via different benchmarks proves its resilience to digital attacks. The detectors response, PSNR and RMSE results show that our algorithm has a better security performance than most of the existing algorithms.

Analog technology has been around for a long time. The use of analog technology is necessary since we live in an analog world. However, the transmission and storage of analog technology is more complicated and in many cases less efficient than digital technology. Digital technology, on the other hand, provides fast means to be transmitted and stored. Digital technology continues to grow and it is more widely used than ever before. However, with the advent of new technology that can reproduce digital documents or images with unprecedented accuracy, it poses a risk to the intellectual rights of many artists and also on personal security. One way to protect intellectual rights of digital works is by embedding watermarks in them. The watermarks can be visible or invisible depending on the application and the final objective of the intellectual work. This thesis deals with watermarking images in the discrete wavelet transform domain. The watermarking process was done using the JPEG2000 compression standard as a platform. The hardware implementation was achieved using the ALTERA DSP Builder and SIMULINK software to program the DE2 ALTERA FPGA board. The JPEG2000 color transform and the wavelet transformation blocks were implemented using the hardware-in-the-loop (HIL) configuration.

Due to the accelerated growth in digital music distribution, it becomes easy to modify, intercept, and distribute material illegally. To overcome the urgent need for copyright protection against piracy, several audio watermarking schemes have been proposed and implemented. These digital audio watermarking schemes have the purpose of embedding inaudible information within the host file to cover copyright and authentication issues. This thesis proposes an audio watermarking model using MATLAB® and Simulink® software for 1K and 2K fast Fourier transform (FFT) lengths. The watermark insertion process is performed in the frequency domain to guarantee the imperceptibility of the watermark to the human auditory system. Additionally, the proposed audio watermarking model was implemented in a Cyclone® II FPGA device from Altera® using the Altera® DSP Builder tool and MATLAB/Simulink® software. To evaluate the performance of the proposed audio watermarking scheme, effectiveness and fidelity performance tests were conducted for the proposed software and hardware-in-the-loop based audio watermarking model.

This thesis addresses authenticity and integrity of medical images using watermarking. Hospital Information Systems (HIS), Radiology Information Systems (RIS) and Picture Archiving and Communication Systems (P ACS) now form the information infrastructure for today's healthcare as these provide new ways to store, access and distribute medical data that also involve some security risk. Watermarking can be seen as an additional tool for security measures. As the medical tradition is very strict with the quality of biomedical images, the watermarking method must be reversible or if not, region of Interest (ROI) needs to be defined and left intact. Watermarking should also serve as an integrity control and should be able to authenticate the medical image. Three watermarking techniques were proposed. First, Strict Authentication Watermarking (SAW) embeds the digital signature of the image in the ROI and the image can be reverted back to its original value bit by bit if required. Second, Strict Authentication Watermarking with JPEG Compression (SAW-JPEG) uses the same principal as SAW, but is able to survive some degree of JPEG compression. Third, Authentication Watermarking with Tamper Detection and Recovery (AW-TDR) is able to localise tampering, whilst simultaneously reconstructing the original image.

Watermarking is a technique used to used to mark the ownership in media such as audio or images by embedding a watermark, e.g. copyrights information, into the media. A good watermarking method should perform this embedding without affecting the quality of the media. Recent methods for watermarking in images uses deep learning to embed and extract the watermark in the images. In this thesis, we investigate watermarking in the hearable frequencies of audio using deep learning. More specifically, we try to create a watermarking method for audio that is robust to noise in the carrier, and that allows for the extraction of the embedded watermark from the audio after being played over-the-air. The proposed method consists of two deep convolutional neural network trained end-to-end on music with simulated noise. Experiments show that the proposed method successfully creates watermarks robust to simulated noise with moderate quality reductions, but it is not robust to the real world noise introduced after playing and recording the audio over-the-air.