1. An image processing apparatus comprising: an acquisition unit configured to acquire an image from an imaging apparatus that captures an image of a physical space; a detection unit configured to detect at least one image feature from the acquired image; a generation unit configured to generate a combined image by combining a predetermined object which emphasizes the detected image feature with the captured image; a display unit configured to display the combined image to a user; a setting unit configured to set an image feature corresponding to the object operated by the user as a disabled image feature or an enabled image feature; a holding unit configured to hold information indicating relationship between three-dimensional position of the set image feature and a parameter indicating whether the set image feature is a disabled image feature or an enabled image feature; and a calculation unit configured to calculate a position and an orientation of the imaging apparatus based on the information.