如何使用 ROS、C++ 和 OpenCV 在地图中定位 2d 图像中的 3d 对象

Question

Let suppose I have a stopped video camera that is recording in front of it, and in the left side of his visual there is a person stopped in his position. If I know the distance in meters between the person and the video camera( in diagonal) , and I know how many pixel there are between the frontal axis of the camera and the person, how can I know the angle between the frontal axis and the person? I'm asking this question because I'm implementing a ROS node that recognize people in an image of the camera and the depth of the objects in it, but I also want to add a marker (that symbolize the person) in a map that is seeing the scene from the above. In the node there are OpenCV libraries also.. Thanks

Answer 1

Here is how I understood the question. Excuse my drawing skills.