Review of Image Annotation for the Evaluation of Computer Vision Algorithms

In the field of computer vision, automated image annotation and object recognition are currently important research topics. It is hoped that these will lead to improved general image understanding which can be usefully applied in Content-based Image Retrieval. Three approaches to image annotation are reviewed: free text annotation, keyword annotation and annotation based on ontologies. An analysis of the keywords which have been used in automated image and video annotation research and evaluation campaigns is then presented. The outcome of this analysis is a list of 525 keywords divided into 15 categories. Given that this list is collected from existing image annotations, it could be used to check the applicability of ontologies describing entities which are portrayable in images.