1. A power supply control apparatus for a printing device, the power supply control apparatus comprising: a transition unit configured to make an apparatus that includes processing units enter a power supply state or a power shutoff state, power being selectively supplied to the processing units in the power supply state; a detector configured to detect a moving object while the apparatus is in the power shutoff state; a first image capturing unit that includes a sensor with a camera function, the first image capturing unit being configured to capture images of a specific area at a time when the detector detects the moving object; a command unit configured to command the transition unit to make the apparatus enter the power supply state in a case where it is determined that the moving object is approaching the apparatus in accordance with image information of the images captured by the first image capturing unit, and to command the transition unit to make the apparatus exit the power supply state in a case where it is determined that the moving object is not approaching the apparatus in accordance with image information of the images captured by the first image capturing unit; a second image capturing unit configured to capture a characteristic image of the moving object that is approaching the apparatus; and an identity recognition unit configured to perform identity recognition for the moving object in accordance with image information of the characteristic image captured by the second image capturing unit.