Content-Based Image Retrieval Using Block Discrete Cosine Transform
نویسندگان
چکیده
Image retrieval is an important problem for accessing large image databases. In this paper, a content-based image retrieval method based on block DCT is proposed. Due to the energy compacting property and the ability of extracting the texture information, discrete cosine transform (DCT) is applied to extract low-level features from the images. Based on the observation that block DCT can reduce the computational complexity of each DCT operation but may lose global view of the image being processed, we are motivated to investigate the relation between the precision rate in image retrieval and the block size of the block DCT. Experiments show that the block DCT with larger block size would perform better than the block DCT with small block size and the ordinary DCT in terms of the precision rate of the content-based image retrieval.
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