More common in high-end video games and movies, you'll see optical tracking of markers, in which a camera is learning where parts of a person's body are by looking for high-contrast areas.

更常见的是在高端视频游戏和电影中，你会看到光学跟踪标记，其中摄像机会通过寻找高对比度区域来了解人身体的哪一部分。