1. An input apparatus that generates information for controlling devices based on a user's motions comprising: memory storing instructions; and at least one processor to execute the instructions to: acquire images; analyze the acquired images and extract image areas representing moving objects that are moved by the user; extract, from the extracted image areas representing the moving objects, coordinates of predefined points of the moving objects and generate motion information representing trajectories of motions of the moving objects; determine, based on the motion information, whether or not predetermined motions are performed and detect, when determined that the predetermined motions are performed, center coordinates of shapes formed by trajectories of the predetermined motions; detect, based on the motion information, specific coordinates on the trajectories of the predetermined motions; generate, based on positional relationships between points defined by the center coordinates and points defined by the specific coordinates, information for controlling the devices by: accessing an information correspondence table stored in the memory that associates the positional relationships between the points defined by the center coordinates and the points defined by the specific coordinates with the information for controlling the devices, and checking the detected center coordinates and the detected specific coordinates with the information correspondence table to specify the corresponding information and generating the information that is specified; wherein the generated information for controlling the devices is different for a first trajectory and a second trajectory, the second trajectory having the same shape and direction as the first trajectory and differing from the first trajectory in the positional relationships between the points defined by the center coordinates and the points defined by the specific coordinates.