14697178
Design of integrated multimedia compression and encryption systems
Two approaches for integrating encryption with multimedia compression systems are studied in this research, i.e., selective encryption and modified entropy coders with multiple statistical models. First, we examine the limitations of selective encryption using cryptanalysis, and provide examples that use selective encryption successfully. Two rules to determine whether selective encryption is suitable for a compression system are concluded. Next, we propose another approach that turns entropy coders into encryption ciphers using multiple statistical models. Two specific encryption schemes are obtained by applying this approach to the Huffman coder and the QM coder. It is shown that security is achieved without sacrificing the compression performance and the computational speed. This modified entropy coding methodology can be applied to most modern compressed audio/video such as MPEG audio, MPEG video, and JPEG/JPEG2000 images.
7629632
Speech content authentication integrated with CELP speech decoders
A speech content authentication scheme, which is integrated with CELP speech coders to minimize the total computational cost is proposed in this research. Speech features relevant to semantic meaning are extracted, encrypted and attached as the header information. A low cost synchronization algorithm is used to resolve mis-synchronization caused by content preserving operations. Silent and tonal regions in the speech are identified with algorithms of low complexity to enhance the precision of integrity verification. This scheme is not only much faster than traditional cryptographic bitstream integrity algorithms, but also more compatible for a variety of applications. Experimental results are collected by using the GSM-AMR speech coder, and statistical analysis is performed to calculate the false positive rate of tamper detection.
6331913
Speech content integrity verification integrated with ITU G.723.1 speech coding
A speech content integrity verification scheme integrated with ITU G.723.1 speech coding to minimize the total computational cost is proposed in this research. Speech features relevant to the semantic meaning are extracted, encrypted and attached as the header information. This scheme is not only much faster than cryptographic bitstream integrity algorithms, but also more compatible with a variable of applications. The speech signal could go through recompression, amplification, transcoding, re-sampling, D/A and A/D conversion and minor white noise pollution without triggering the verification alarm.
27585937
Multi-modal Sign Icon Retrieval for Augmentative Communication
This paper addresses a multi-modal sign icon retrieval and prediction technology for generating sentences from ill-formed Taiwanese sign language (TSL) for people with speech or hearing impairments. The design and development of this PC-based TSL augmented and alternative communication (AAC) system aims to improve the input rate and accuracy of communication aids. This study focuses on 1) developing a effective TSL icon retrieval method, 2) investigating TSL prediction strategies for input rate enhancement, 3) using a predictive sentence template (PST) tree for sentence generation. The proposed system assists people with language disabilities in sentence formation. To evaluate the performance of our approach, a pilot study for clinical evaluation and education training was undertaken. The evaluation results show that the retrieval rate and subjective satistactory level for sentence generation was significantly improved.
12571074
Hand Motion Recognition for the Vision-based Taiwanese Sign Language Interpretation
In this paper we present a system to recognize the hand motion of Taiwanese Sign Language (TSL) using the Hidden Markov Models (HMMs) through a vision-based interface. Our hand motion recognition system consists of four phases: construction of color model, hand tracking, trajectory representation, and recognition. Our hand tracking can accurately track the hand positions. Since our system is recognized to hand motions that are variant with rotation, translation, symmetric, and scaling in Cartesian coordinate system, we have chosen invariant features which convert our coordinate system from Cartesian coordinate system to Polar coordinate system. There are nine hand motion patterns defined for TSL. Experimental results show that our proposed method successfully chooses invariant features to recognition with accuracy about 90%.
17356448
Web Directory Integration Using Conditional Random Fields
The purpose of integrating web directories is to transfer instances from a source to a target directory. Unlike conventional text categorization, in directory integration, there is extra information about the source directory that can be used to improve the classification accuracy. Many approaches exploit the measured similarity between two corresponding classes to enhance traditional text classifiers. These methods perform well if the topics of two classes are very similar, but they could lead to misclassification if the topics are dissimilar. We propose a directory integration approach based on the conditional random fields (CRFs) model, and model the integration process using a finite-state model. The advantage of using CRFs is that the transition features naturally include information about the relations between classes. Our results show that CRFs outperform conventional text classifiers. In addition, CRFs allow us to apply complex features to integrate the information about the contents of class and their labels. The performance of our approach can be improved by applying these features, especially for instances whose source and target classes are moderately similar
26616615
On a Class of Multistage Interconnection Networks
A baseline network and a configuration concept are introduced to evaluate relationships among some proposed multistage interconnection networks. It is proven that the data manipulator (modified version), flip network, omega network, indirect binary n-cube network, and regular SW banyan network (S = F = 2) are topologically equivalent. The configuration concept facilitates developing a homogeneous routing algorithm which allows one-to-one and one- to-many connections from an arbitrary side of a network to the other side. This routing algorithm is extended to full communication which allows connections between terminals on the same side of a network. A conflict resolution scheme is also included. Some practical implications of our results are presented for further research.
11048111
Modified Chinese remainder theorem and its application to proxy signatures
Chinese Remainder Theorem has been used for hundreds of years and has been applied to many domains such as integers and polynomials. An assumption made is that the component moduli are pairwise co-prime. In this paper, first we remove this assumption; then we give an algorithm to find whether a given system of congruent equations has a solution, and if so, how to find the solution in an efficient manner. Further we apply the modified Chinese Remainder Theorem to design proxy signatures.