关键词: 基于内容的图像检索, 商标, 傅里叶描述子, 尺度不变特征转换（SIFT）

Abstract: According to the shape characteristics of trademark images, this paper proposes a trademark retrieval algorithm combining the image global features and local features. The global features capture the image gross contour. It can be used to rapidly build candidate image database. The local features can be used to more accurately match with candidate image. This paper extracts Fourier Descriptors（FDs） of the retrieved image and sorts them according to similarity. Candidate images are formed. The query image accurately match with candidate images using the SIFT features. Experimental results show that this method not only keeps SIFT features the perfect descriptive ability, but also reduces the computation complexity and has higher precision.

Key words: Content-Based Image Retrieval（CBIR）, trademark, Fourier descriptors, Scale Invariant Feature Transform（SIFT）