随着多媒体技术和计算机网络的飞速发展，图像的应用日益广泛，基于内容的图像检索技术成为当前多媒体研究的热点之一。基于内容的图像检索是一种利用图像的颜色、纹理、形状等视觉特征进行图像检索的技术。然而由于信息的复杂多样，图像的内容描述方法缺乏规范，导致了基于内容的图像检索系统中存在通用性差的问题。MPEG-7正是为规范多媒体内容描述而启动的国际标准，它的制定使得快速、有效的查询和访问各种多媒体成为可能。 本文的研究工作主要是基于MPEG-7标准，综合利用MPEG-7颜色、纹理特征及其描述符实现对图像的检索，目标是开发出一个基于内容的图像检索的原型系统： （1）研究了基于内容的图像检索系统，在介绍图像检索系统的发展及其研究现状的基础上给出了基于几种内容特征(颜色、纹理、形状)的图像检索方法。 （2）介绍了MPEG-7标准。包括MPEG-7的主要元素、组成部分以及MPEG-7的范围。着重从基本结构、颜色描述符、纹理描述符、形状描述符等几个方面讨论了MPEG-7中视觉特征的描述与表示。并讨论了MPEG-7与基于内容的图像检索的联系。 （3）在研究了MPEG-7中描述符提取方法的基础上，将HSV颜色空间量化为36维，同时对图像的不同区域配以不同权重的方法进行描述；而对于纹理特征，则采用了改进的边缘直方图特征进行描述。 （4）综合利用MPEG-7颜色、纹理特征的图像检索方法实现了基于MPEG-7与内容的图像检索原型系统，实验结果表明，综合两种特征的图像检索较单一特征的图像检索，检索结果更好。

With the development of the multimedia and computer network technology, the application of the image is more and more extensive; Content-based image retrieval (CBIR) technology becomes one of the most active fields in multimedia retrieval. CBIR is an image retrieval technology, which synthesizes various visual features in digital image, such as color, textual, and shapes features. However, due to the complexity of the information, the lack of standard for the description of image content induces low interoperability among CBIR systems. To meet this challenge, MPEG-7 was developed as a solution to the normative description of audio-visual content. MPEG-7 relates the description with its content, and enables the effective and efficient query and access to multimedia content. This thesis focuses on the bottom basic features offered by MPEG-7, and combining MPEG-7 color, texture features and descriptor of the image, and the goal is to develop an image retrieval prototype system. Section I studies CBIR. By introducing the background of CBIR, this thesis gives several image retrieval methods based on color, texture and shape features. Section II introduces the MPEG-7 standard with the main elements, parts and the scope of the MPEG-7 standard, etc. This section emphasizes on the basic structures and descriptors that covers following basic visual features: color, texture, shape and etc. Then an analysis is made of the relation between CBIR and the MPEG-7 standard in this section. Section III on the basis of the studies of the MPEG-7 descriptors extraction method, makes an description of different weights method for different image regions with the 36-dimensionl quantification HSV color space; while in terms of the texture descriptor, the improved edge histogram descriptor is used. Section IV implements the image retrieved prototype system using two image retrieval methods based on color and texture discriptor. This section also gives the system design, system implement and the results of the experiment. In the end, this section analyses the results, which shows that two synthesized image feature retrieval is better than single one.