说明：  Q. Zhou, J.K. Aggarwal. Tracking and Classifying Moving Objects from Video. 这篇文章另辟蹊径，利用“紧凑度值的变化、运动方向的变化”，区分人、人群、机动车。达到良好的分类效果。是运动目标分类领域的好文章。
(Q. Zhou, JK Aggarwal. Tracking and Classifying Moving Objects from Video. This article open a new path, by using the " compact value changes, the changes in the direction of sport" , to distinguish between people, groups, motor vehicle. Achieve good classification results. Are the area of target classification exercise good article.)