In recent years, wireless sensor and actor networks (WSANs) have been extensively deployed to monitor physical environment and facilitate decision making based on data collected. Emerging applications such as road surveillance highlight some interesting research issues in WSANs, including coordination problems in sensor-actor or actor-actor communications. In this paper, the issue of choosing a set […]
Archives for September 2011
Loss Performance Modeling for Hierarchical Heterogeneous Wireless Networks With Speed-Sensitive Call Admission Control
A hierarchical overlay structure is an alternative solution that integrates existing and future heterogeneous wireless networks to provide subscribers with better mobile broadband services. Traffic loss performance in such integrated heterogeneous networks is necessary for an operator’s network dimensioning and planning. This paper investigates the computationally efficient loss performance modeling for multiservice in hierarchical heterogeneous […]
Lossy Compression and Iterative Reconstruction for Encrypted Image
This work proposes a novel scheme for lossy compression of an encrypted image with flexible compression ratio. A pseudorandom permutation is used to encrypt an original image, and the encrypted data are efficiently compressed by discarding the excessively rough and fine information of coefficients generated from orthogonal transform. After receiving the compressed data, with the […]
Computational Perceptual Features for Texture Representation and Retrieval
A perception-based approach to content-based image representation and retrieval is proposed in this paper. We consider textured images and propose to model their textural content by a set of features having a perceptual meaning and their application to content-based image retrieval. We present a new method to estimate a set of perceptual textural features, namely […]
Color Extended Visual Cryptography Using Error Diffusion
Color visual cryptography (VC) encrypts a color secret message into color halftone image shares. Previous methods in the literature show good results for black and white or gray scale VC schemes, however, they are not sufficient to be applied directly to color shares due to different color structures. Some methods for color visual cryptography are […]