关键词: 图像标注, 机器视觉, 机器学习

Abstract: The target of image annotation is to affine text information to corresponding images，which helps a lot in managing and retrieving large collections of images.Although it has been studied for several years，it’s still a challenging research area in computer vision and machine learning.Various of methods have been utilized to annotate unlabeled images.This paper reviews the state of the art algorithms and models for annotating images with keywords，including traditional classification methods，relevance models，topic models，utilizing context information with random fields and annotation with the help of Internet.Several challenges of image annotation are also discussed in this paper.

Key words: image annotation, computer vision, machine learning