1. A setting apparatus for setting a detection processing region in an image where detection processing for detecting a specific object is performed by a processor, the processor comprising: an acquisition unit configured to acquire an input from a user interface to designate the detection processing region in the image where the detection processing for detecting the specific object is performed; an obtaining unit configured to obtain evaluation information based on a processing load of the detection processing in the detection processing region which is in the image and is designated by the input from the user interface; and a setting unit configured to set the detection processing region corresponding to a size smaller than a size of the detection processing region which is in the image and is designated by the input from the user interface, to detect the specific object in accordance with the evaluation information obtained by the obtaining unit, wherein the setting unit sets the detection processing region according to time information and/or situation information related to image taking.