Operations of the present disclosure may include receiving a group of images taken by a camera over time in an environment. The operations may also include identifying a first position of an object in a target region of the environment in a first image of the group of images and identifying a second position of the object in a second image of the group of images. Additionally, the operations may include determining an estimated trajectory of the object based on the first position of the object and the second position of the object. The operations may further include, based on the estimated trajectory, estimating a ground position in the environment associated with a starting point of the estimated trajectory of the object. Additionally, the operations may include providing the ground position associated with the starting point of the estimated trajectory of the object for display in a graphical user interface.