Rakhi C. Motwani

A Proposed Digital Rights Management System for 3D Graphics Using Biometric Watermarks

This paper proposes a new DRM system for 3D graphics that makes use of biometric watermarking technology. The presented solution utilizes an image of a biometric trait e.g. face or fingerprint, and embeds it into the 3D graphics as a watermark. This biometric watermark is then used to authenticate a legitimate user. Details for the components of the DRM framework are presented. Adoption of biometric watermarking allows the DRM system to provide consumers unrestricted access to the graphics along with limiting graphics content access to only legitimate users, thereby protecting artists from large scale online piracy. A detailed survey of existing DRM solutions for 3D graphics is provided to identify the limitations of each implementation which offers either restrictive content usage scenarios or is ineffective in preventing unauthorized usage.

Towards a scalable and interoperable global environmental sensor network using Service Oriented Architecture

Sensor networks are critical infrastructures for monitoring environmental variables, allowing evaluation of long-term trends and changes in the interaction of atmospheric, ecologic, and hydrologic processes. However, due to lack of coordination between large-scale environmental observation systems that have been set up around the globe, the wealth of information collected by sensor networks is not exploited to its full potential. Since there is no central organization tying these various systems together, data acquisition and dissemination methods are inconsistent and public accessibility to these observation systems is restricted to the methods chosen at the individual project level. The ability to easily discover, access, and interact with observational instruments and use real-time sensory data spread across different environmental observatories is limited. Interoperability of sensor network assets is essential to producing improved projections, models, analyses, and assessments at a global scale. To this end this paper presents the architectural design for a scalable, interoperable and real-time environmental sensor network. The proposed architectural design also provides support for dynamic reconfiguration of sensors in response to changing environmental conditions, and facilitates secure sensor access and delivery of observations to a distributed community of users using standardized mechanisms based on Open Geospatial Consortium standards. The outlined architecture uses an Event-Driven Service Oriented Architecture, with Enterprise Service Bus as its backbone messaging transport layer.

Collocated dataglyphs for large message storage and retrieval

In contrast to the security and integrity of electronic files, printed documents are vulnerable to damage and forgery due to their physical nature. Researchers at Palo Alto Research Center utilize DataGlyph technology to render digital characteristics to printed documents, which provides them with the facility of tamper-proof authentication and damage resistance. This DataGlyph document is known as GlyphSeal. Limited DataGlyph carrying capacity per printed page restricted the application of this technology to a domain of graphically simple and small-sized single-paged documents. In this paper the authors design a protocol motivated by techniques from the networking domain and back-up strategies, which extends the GlyphSeal technology to larger-sized, graphically complex, multi-page documents. This protocol provides fragmentation, sequencing and data loss recovery. The Collocated DataGlyph Protocol renders large glyph messages onto multiple printed pages and recovers the glyph data from rescanned versions of the multi-page documents, even when pages are missing, reordered or damaged. The novelty of this protocol is the application of ideas from RAID to the domain of DataGlyphs. The current revision of this protocol is capable of generating at most 255 pages, if page recovery is desired and does not provide enough data density to store highly detailed images in a reasonable amount of page space.

Watermark Embedder Optimization for 3D Mesh Objects Using Classification Based Approach

This paper presents a novel 3D mesh watermarking scheme that utilizes a support vector machine(SVM) based classifier for watermark insertion. Artificial intelligence(AI)based approaches have been employed by watermarking algorithms for various host mediums such as images, audio, and video. However, AI based techniques are yet to be explored by researchers in the 3D domain for watermark insertion and extraction processes. Contributing towards this end, the proposed approach employs a binary SVM to classify vertices as appropriate or inappropriate candidates for watermark insertion. The SVM is trained with feature vectors derived from the curvature estimates of a 1-ring neighborhood of vertices taken from normalized 3D meshes. A geometry-based non-blind approach is used by the watermarking algorithm. The robustness of proposed technique is evaluated experimentally by simulating attacks such as mesh smoothing, cropping and noise addition.

Wavelet based fuzzy perceptual mask for images

One of the characteristics of the Human Visual System (HVS) is to model the sensitivity of the human eye at each coordinate location in the image. This paper explores the use of fuzzy logic for building a non-linear HVS model for perceptual masking in wavelet domain. The fuzzy input variables corresponding to brightness, edge sensitivity, and texture are computed for each wavelet coefficient at different scales in an image. The output of the fuzzy system is a single value which gives a perceptual value for each corresponding wavelet coefficient. This paper proposes a novel method of constructing perceptual mask in wavelet domain using fuzzy logic.

Robust watermarking of 3D skinning mesh animations

This paper presents a novel robust watermarking algorithm for 3D skinning mesh animations by embedding the watermark in skin weights in addition to key frames. This method can be used for copyright protection, tamper proofing or content annotation purposes. The proposed watermark is immune to noise attacks on key frames and skin weights, key frame dropping and frame modification and is perceptible invisible as well. Experimental results verified that the proposed algorithm has good robustness against attacks and maintains invisibility by preprocessing the animation data sets by key frame decimation.

Towards Benchmarking of Video Motion Tracking Algorithms

The environment in which video motion needs to be tracked, places several constraints on the design of the tracking system. Current datasets which are used to evaluate and compare video motion tracking algorithms use a cumulative performance measure without thoroughly analyzing the effect of these different constraints imposed by the environment. There is need to build a heuristic framework which analyses these constraints as parameters of the framework and their effect on selection or design of tracking algorithm. The emphasis in this paper is to identify these parameters which will lay a foundation for defining subjective measures for the comparison of performance evaluation of tracking algorithms.

Voice biometric watermarking of 3D models

Digital watermarking provides a solution to piracy and copyright protection of 3D multimedia content by embedding a hidden piece of information in the original content. This hidden piece of information travels with the 3D multimedia in the distribution chain and assists in verifying legitimate ownership and tracing piracy. This paper proposes a voice-based biometric watermark for 3D graphics for the purpose of owner identification, traitor tracing and access control schemes. A voice print is generated using a Gaussian mixture model representation of Mel-frequency cepstral coding coefficients of an individuals speech. This voice print is inserted as the watermark. The proposed technique generates a semi-fragile watermark, which is tolerant to a designated class of transformations. Experimental results indicate that the biometric watermark is resistant to cropping, low levels of Gaussian noise addition, and is intolerant to mesh smoothing attacks.

Tamper Proofing 3D Models

This paper describes a novel algorithm designed for tamper proofing of 3D models. Fragile watermarking is a known technique for detecting location of tamper in the artwork. However, to detect even minute changes, the watermark needs to be distributed throughout the 3D model. This poses as a challenge since watermarking all vertices can cause perceptible distortion. The proposed algorithm solves this problem by inserting a watermark in all the vertices of a 3D model. The watermark is randomly added to each and every vertex of the 3D model by modifying the coordinate location of the vertices. Genetic Algorithms have been used to find the near optimal coordinate location of the watermarked vertex. The fitness function chosen is the Signal to Noise Ratio of the 1-ring neighbourhood of the vertex. This ensures that there exists no distortion in the watermarked model. The proposed approach is computationally inexpensive and experimental results indicate that the algorithm can efficiently detect location of any kind of unauthorized data modification.

An Intelligent Learning Approach for Information Hiding in 3D Multimedia

This paper presents a new watermarking algorithm for 3D triangular mesh models that is based on surface curvature estimation and supervised learning. A feedforward backpropagation neural network is adopted for selecting vertices for watermark insertion. A variety of 3D models with varying degrees of surface curvature are used to train and simulate the neural network. An array of neural networks is used for vertices with different valences to achieve higher watermark embedding capacity. A gray scale bitmap image is used as the watermark. The watermark extraction process is informed and needs the original watermark and 3D model. Experimental results evaluate the embedding capacity, imperceptibility and robustness of the proposed algorithm and simulate various attacks including noise addition, smoothing and cropping.