Design of an Efficient content based image retrieval system in P2p environment

Abstract

With the large multimedia databases becoming a reality in various domains, methods for organizing image databases and for efficient retrieval from them have become important. Conventional text based techniques have been used for image retrieval for many years. It has certain drawbacks such as language limitation and subjectivity of human perception. Furthermore, annotation process of these images is quite time consuming. Text is man s creation, while typical images are a mere replica of what man has seen since birth, interpretation of what we see is hard to characterize. This motivates the need of image retrieval based on the visual content of an image. newlineContent-based image retrieval (CBIR) is the process of retrieving desired images from a large collection on the basis of the visual contents of an image (such as color, texture, shape and spatial layout) that can be automatically extracted from the images. newlineCurrently, most of the CBIR systems are based on the centralized computing model. Some are stand-alone applications while others are web based systems. A centralized system maintains central nodes to handle the query requests. It keeps the entire feature descriptor database in a centralized server. Upon retrieving the relevant images according to feature similarity measures, the content will be transferred directly from the content server to the requesting host. The drawback of the centralized system is its limited scalability for handling growing volumes of retrieval requests and large image databases. newlineIn order to provide better scalability, we have proposed a decentralized system based on peer to peer (P2P) paradigm. Each node in a P2P network acts as a both, client for requesting image and a server for redistributing the images [23]. In P2P file systems, files are stored at the end user machines (peers) rather than on a central server and, as opposed to the traditional client-server model, files are transferred directly between peers. In general, P2P systems allow a decentralized sharing of distri