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With the rapid development of the Internet, finding desired images from numerous images has become an important research topic. In this paper, we propose an image retrieval system facilitating retrieval time and accuracy. Since the performance of image retrieval is deeply influenced by image features and retrieval methods. Five different types of features and five different methods are used to find the best combination for an image retrieval system. First, we segment out the main object in an image and then extract its features. Next, relevant features are selected from the original feature set for facilitating image retrieval, using the SAHS algorithm. Then, five methods based on AND/OR-construction are proposed to build the image retrieval model, using the relevant features. Finally, the experimental results not only show that our methods are more effective than the other state-of-the-art methods but also present some observations never explored by the previous research.
相似文献Video synopsis is an effective solution for fast browsing and retrieval of long surveillance videos. It aims to shorten long video sequences into its equivalent compact video representation by rearranging the video events in the temporal domain and/or spatial domain. Conventional video synopsis methods focus on reducing the collisions between tubes and maintaining their chronological order, which may alter the original interactions between tubes due to improper tube rearrangement. In this paper, we present an approach to preserve the relationships among tubes (tracks of moving objects) of the original video in the synopsis video. First, a recursive tube-grouping algorithm is proposed to determine the behavior interactions among tubes in a video and group the related tubes together to form tube sets. Second, to preserve the discovered relationships, a spatio-temporal cube voting algorithm is proposed. This cube voting method optimally rearranges the tube sets in the synopsis video, minimizing false collisions between tubes. Third, a method to estimate the duration of the synopsis video is proposed based on an entropy measure of tube collisions. The extensive experimental results demonstrate that the proposed video synopsis framework condenses videos by preserving the original tube interactions and reducing false tube collisions.
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