摘要
针对离散余弦变换(DCT)压缩域中图像检索算法存在的问题,提出了一种新的检索算法.利用DCT块中系数的分布特性,构造边缘空间分布图,采用一种边缘空间分布特征矢量对图像内容进行描述.同时,考虑到DCT块中的能量对最终检索结果的影响,又采用每类边缘分布图中DCT块的能量和作为图像的另一种特征.该算法不需要完全解压缩,计算复杂度低,不仅考虑了DCT块的空间分布,又考虑了块内的能量分布,避免了由于DCT块统计分布信息相同而能量不同造成的误检漏检情况.实验结果表明,该算法具有较好的检索性能.
Image retrieval in discrete cosine transform （DCT） compressed domain is proposed by introducing the spatial information and the energy of DCT blocks into the feature extraction. According to the distribution of DCT coefficients, the spatial distribution map is constructed and spatial distribution feature is given. Meanwhile, the effect of the energy of DCT blocks on retrieval precision is consid- ered, an energy distribution feature is presented as another feature. The energy distribution of DCT blocks and the spatial distribution of DCT coefficients are taken into account for avoiding the retrieval mistaken and lose. The experiment results show that the new method has a good performance both in retrieval efficiency and effectiveness.
出处
《北京邮电大学学报》
EI
CAS
CSCD
北大核心
2008年第5期5-8,共4页
Journal of Beijing University of Posts and Telecommunications
基金
河南省教育厅自然科学基础研究基金项目(2007520019；2008B520012；2008B520015)
关键词
基于内容的图像检索
离散余弦变换
压缩域
空间分布图
content-based image retrieval
discrete cosine transform
compressed domain
spatial distribution map
