Min-Jen Tsai

A computing coordination based fuzzy group decision-making (CC-FGDM) for web service oriented architecture

As the demands for faster data processing and enterprise computing are increasing, the traditional client/server architecture has gradually been replaced by Grid computing or the peer-to-peer (P2P) model which can share the content or resources over the network. In this paper, a new computing architecture - computing power services (CPS) - has been applied to utilize web services and business process execution language for overcoming the issues about flexibility, compatibility and workflow management. CPS is a lightweight web services based computing power-sharing architecture, and suitable for enterprise computing tasks which can be executed in the batch processes within a trusty network. However, a real-time load balance and dispatching mechanism is needed for distributed-computing architecture like CPS in order to handle computing resources efficiently and properly. Therefore, a fuzzy group decision-making based adaptive collaboration design for CPS is proposed in this paper to provide the real-time computation coordination and quality of service. In this study, the approach has been applied to analyze the robustness of digital watermark by filter bank selection and the performance can be improved in the aspect of speedup, stability and processing time. This scheme increases the overall computing performance and shows stability for the dynamic environment.

Using decision fusion of feature selection in digital forensics for camera source model identification

Digital forensics, which identifies the characteristics and origin of a digital device, has become a new field of research. If digital content will serve as evidence in court, similar to its non-digital counterparts, digital forensics can play a crucial role in identifying the source model or device. To achieve this goal, the relationship between an image and its camera model will be explored. Various image-related and hardware-related features are utilized in the proposed model by a support vector machine approach along with decision fusion techniques. Furthermore, the optimum feature subset to achieve the highest accuracy rate is also explored.

Source color laser printer identification using discrete wavelet transform and feature selection algorithms

It has lately become an important research area of digital forensics to identify the characteristics and the originality of the digital devices. This paper presents a novel method to identify source color laser printer by using discrete wavelet transform and feature selection algorithms. To explore the relationship between color laser printers and color images obtained by scanning printed documents, the proposed approach utilizes image processing techniques and data exploration methods to calculate the features by applying statistical analysis on discrete wavelet transform of scanned images. A model of support vector machines sequentially will be created and trained by using these features to identify the source brand and model of color laser printer. In this study, 10 models of color laser printers and color toner from 6 different brands are used for the experiments. The experimental results reach up to 92.4% identification rate which is significantly superior to the existing known method by 5.5%. The testing performance justifies the proposed identification method is very useful for source color laser printer identification.

Digital forensics for printed source identification

Recently, digital forensics, which involves the collection and analysis of the origin digital device, has become an important issue. Digital content can play a crucial role in identifying the source device, such as serve as evidence in court. To achieve this goal, we use different texture feature extraction methods such as gray-level co-occurrence matrix (GLCM) and discrete wavelet transform (DWT), to analyze the Chinese printed source in order to find the source of printers. Furthermore, we also explore the optimum feature subset by using feature selection techniques and using support vector machine (SVM) to identify the source model of the documents. The average experimental results attain a 98.64% identification rate which is significantly superior to the existing known method by 1.2%. This higher testing performance demonstrates that the proposed identification method is very useful for source laser printer identification.

Service-oriented grid computing system for digital rights management (GC-DRM)

Service-oriented computing and applications have recently gained significant attention since they provide new service infrastructure and development of service-oriented technology. Under such trend and ubiquitous computing requirement, grid computing is becoming popular in scientific and enterprise computing due to its flexible deployment and implementation. In this paper, we proposed a service-oriented digital rights management (DRM) platform based on grid computing (called GC-DRM) which is in the compliance of Grid Portal standards by using porlet. The platform integrates Globus Toolkit 4 and Condor 6.9.2 and uses web 2.0 to construct the web-based user interface for providing job submission, control, management, monitor for DRM services. GC-DRM can provide different categories of services which include watermark embedding and extraction, image scrambling, visible watermark embedding, image tamper-detection and recovery. In addition, GC-DRM has been applied to analyze the robustness of digital watermark by filter bank selection and the performance can be improved in the aspect of speedup, stability and processing time compared with NaradaBrokering based Computing Power Services (NB-CPS) and Web Services based Computing Power Service (WS-CPS). Therefore, GC-DRM can be concluded as a superior service-oriented computing which provides the user friendly environment with efficient DRM service performance based on grid computing architecture.

Distributed computing power service coordination based on peer-to-peer grids architecture

As computational speed, storage capacity, and communication technologies steadily progress to the advanced levels, many business employments have utilized these improvements to aggregate distributed resources in various enterprise collaborating functionalities. Recently, grid computing has been identified as a critical technology by industry for enterprise computing and business-to-business computing. The concept of peer-to-peer (P2P) network is also evolving to an expanded usage in distributed networks for sharing the resources like the content files or real-time data for enterprise applications. Therefore, it is natural to include the grids and P2P to support environments that have features of both limiting case. In this paper, a new computing design - NaradaBrokering based Computing Power Services (NB-CPS) - has been applied to utilize the P2P grid to integrate the computational grids, distributed objects, P2P networks under the hybrid environment. In this study, the approach has been applied to analyze the robustness of digital watermark by filter bank selection and the performance can be improved in the aspect of speedup, stability and processing time. NB-CPS is not only suitable for executing computing works which are able to run in batches, but also be able to solve current issues in Web Services based Computing Power Service (WS-CPS) such as system resilience, fault tolerance, efficiency of job scheduling and the instability in congested network environment.

VoiceXML dialog system of the multimodal IP-Telephony—The application for voice ordering service☆

Abstract The development of IP-Telephony in recent years has been substantial. The improvement in voice quality, the integration between voice and data, especially the interaction with multimedia has made the 3G communication more promising. The value added services of Telephony techniques alleviate the dependence on the phone and provide a universal platform for the multimodal telephony applications. For example, the web-based application with VoiceXML has been developed to simplify the human–machine interaction because it takes the advantage of the speech-enabled services and makes the telephone-web access a reality. However, it is not cost-efficient to build voice only stand-alone web application and is more reasonable that voice interfaces should be retrofitted to be compatible or collaborate with the existing HTML or XML-based web applications. Therefore, this paper considers that the functionality of the web service should enable multiple access modalities so that users can perceive and interact with the site in either visual or speech response simultaneously. Under this principle, our research develops a prototype system of multimodal VoIP with the integrated web-based Mandarin dialog system which adopts automatic speech recognition (ASR), text-to-speech (TTS), VoiceXML browser, and VoIP technologies to create user friendly graphic user interface (GUI) and voice user interface (VUI). The users can use traditional telephone, cellular phone, or even VoIP connection via personal computer to interact with the VoiceXML server. In the mean time, the users browse the web and access the same content with common HTML or XML-based browser. The proposed system shows excellent performance and can be easily incorporated into voice ordering service for a wider accessibility.

Japanese character based printed source identification

Due to the advances of digital technology, digital contents are widely accepted all over the world. Since the criminal counterfeits and copyright infringement is still under study for the new digital media, there is an increasing need called digital forensics, which involves the collection and analysis of the original digital device, has become an important issue. This study offers a universal approach to extract the important statistical features from Gray Level Co-occurrence Matrix (GLCM), Discrete Wavelet Transform (DWT), Spatial filter, Wiener filter and Gabor filter to identify the printer source for Japanese characters. The average experimental results achieves high identification rate at 94.23% which is significantly superior to the existing known method of using GLCM at 77.31%. The result is also better than the technique for Chinese character identification method at 88.77%. This superior testing performance demonstrates that the proposed identification technique is very effective for Japanese character based source laser printer identification.

A game-theoretic framework for the security system of visible watermarking

Research highlights? Determine the equilibrium of optimal security strategies between encoder and attacker and the optimal trade-off between the intensity of embedded watermark and the perceptual translucence for visible watermark. ? The watermark embedding problem is formulated as a dynamic non-cooperative game with complete information while the optimal strategy is defined by the Nash equilibrium of the game. ? The game-theoretic framework determines the transmission strategy using utility optimization according to the fluctuation of watermark states. Perfect digital watermarking systems are contained two characteristics. One is the robustness that it need be resistant to geometric attacks in addition to common image processing tasks, such as JPEG compression. The other one is to preserve the image quality after embedding. However, the requirement of robustness and quality for watermark are conflicted with each other. How to determine the equilibrium of optimal security strategies between encoder and attacker and the optimal tradeoff between the intensity of embedded watermark and the perceptual translucence for visible watermark is still remained as one of the most challenging research topics in image watermarking. Therefore, in order to achieve the best tradeoff between the embedding energy of watermark, the quality of perceptual watermark translucence and the image fidelity after attacks, we propose a system architecture which is based on the game-theoretic approach that provides an optimum solution for the decision maker by studying the intensity and perceptual efficiency. The game-theoretic approach determines the transmission strategy using utility optimization according to the fluctuation of watermark states. The watermark embedding problem is formulated as a dynamic non-cooperative game with complete information while the optimal strategy is defined by the Nash equilibrium of the game. The experimental results demonstrate the feasibility of the proposed approach which allows the watermark encoder to obtain the best adaptive watermarking strategy in the different texture under attacks. Additionally, we demonstrate that the proposed system could help each user to choose the optimal transmission power to maximize its utility based on other constant parameters and resolve security issue of visual communication.

Tree group based Wavelet Watermarking using Energy Modulation and Consistency Check (WW-EMCC) for digital images

Wavelet tree based watermarking algorithms are generally using the energy difference among grouped wavelet coefficients for invisible watermark embedding and extraction. According to cryptanalysis of wavelet tree quantization (WTQ) scheme, the robustness of watermarking is weak if the wavelet tree group coefficients are only unilaterally modulated. Therefore, bilaterally modulated techniques like modified wavelet tree quantization (MWTQ) and wavelet tree group modulation (WTGM) improve the security since the attackers can not decipher how tree coefficients are modulated. However, MWTQ needs the wavelet tree group information as the extra information which results the method is not purely blind for watermark extraction. For that matter, a novel wavelet tree group based watermarking using energy modulation and consistency check (WW-EMCC) is proposed in this study which not only resists the cryptanalysis attacks but also provides the dual function of choices for blind (WW-EMCCB) and non-blind (WW-EMCCN) watermark embedding. The essence of WW-EMCC design is to embed the watermark in the tree group coefficients as well as the relationship between the tree groups. Such approach extends the bilateral modulation into higher dimension of modulation and increase the robustness of security. In addition, WW-EMCC can even be modified as a captioning watermarking with lossless image quality which integrates watermarking and cryptography for copyright protection. This study has performed intensive comparison for the proposed scheme with WTQ, MWTQ and WTGM under various geometric and nongeometric attacks. The experimental results demonstrate that the proposed technique yields better performance with higher degree of robustness.