This paper is concerned with the indexing and retrieval of images based on features extracted directly from the JPEG discrete cosine transform (DCT) domain. We examine possible ways of manipulatingDCT coe$cients by standard image analysis approaches to describe image shape, texture, and color. Through the Mandala transformation, our approach groups a subset of DCT coe$cients to form ten blocks....

Whereas in language words of high frequency are generally associated with low content [Bookstein, A., & Swanson, D. (1974). Probabilistic models for automatic indexing. Journal of the American Society of Information Science, 25(5), 312–318; Damerau, F. J. (1965). An experiment in automatic indexing. American Documentation, 16, 283–289; Harter, S. P. (1974). A probabilistic approach to automatic...

Visually meaningful patterns (visual patterns) are a set of predefined image blocks representing information the human visual system is very sensitive to. A colour image coding technique based on visual patterns is introduced. An image is divided into small blocks each of which is mapped to one of the visual patterns. Each block can then be represented by the pattern and by the colour informati...

This paper proposes TSKT-oblivious RAM (ORAM), an efficient multi-server ORAM construction, to protect a client’s access pattern to outsourced data. TSKT-ORAM organizes each of the server storages as a k-ary tree and adopts XOR-based private information retrieval (PIR) and a novel delayed eviction technique to optimize both the data query and data eviction process. TSKT-ORAM is proven to protec...

Digital maps can be stored and distributed electronically using compressed raster image formats. We introduce a storage system for the map images that supports compact storage size, decompression of partial image, and smooth transitions between various scales. The main objective of the proposed storage system is to provide map images for real-time applications that use portable devices with low...

Digital maps can be stored and distributed electronically using compressed raster image formats. We introduce a storage system for the map images that supports compact storage size, decompression of partial image, and smooth transitions between various scales. The main objective of the proposed storage system is to provide map images for real-time applications that use portable devices with low...