Detection of Abnormal Objects in a Scene based on Local Features

A method for detecting an abnormal object in video images is proposed. We define abnormal object as an object that does not appear in usual scenes. The detection system is trained with video images of usual scenes, and then detects abnormal objects in new input video images. The proposed method detects an abnormal object by assuming an object as a set of local features and ignoring the positional relationship between local features. SIFT algorithm is used for detecting and describing local features. The proposed method does not need segmentation of the region of an object and expected to be robust to occlusion and cluttered background.