Research And Implementation Of Content-Based Image Retrieval Technology

Content-based image retrieval (CBIR) is a hotspot of research in multimedia information processing field, and has capacious developed foreground. CBIR seems to be highly task-dependent. In practice, special algorithms are taken according to special application. To slove this problem, this paper analyzed the method of feature extraction, and presented a new method of shape feature extraction. In addition, we study the technology of semantic retrieval and compressed domain image retrieval. On the basis of it, a system prototype of CBIR is designed.On the aspect of feature extraction, we analyzed separately color feature extraction, texture feature extraction and shape feature extraction and realized frequently used methods, like color histogram, co-occurrence matrix and so on. On the basis of shape context, a new shape feature extraction method called Shape context by choosing the edge points self-adaptively based on genetic algorithm is proposed. Experiments show that the method acquired better effect compared with shape context.On the aspect of semantic retrieval, we proposed a new method based on object region on the basis of analyzing frequently used semantic retrieval methods. In addition, to overcome the drawback of query vector modified feedback method, a new method named weighted query vector modified is realized. Experiments show the methods are satisfactory.On the aspect of compressed domain image retrieval, we analyzed the retrieval methods based on JPEG and JPEG2000 on the basis of analyzing frequently used compressed domain image retrieval methods. At last, we realized a method based on JPEG image, Experments show the method aquired better retrieval effect.A system prototype of content-based image retrieval is designed and realized on the basis of it. The system can retrieval image using the methods of this paper, and user can feedback by his subjective evaluation. In the user interface, we designed three query image select method. By this way, user can select query image easily. Experiments show that the system acquired better retrieval effect.