Patent ID: 8396387

Claim:
An image forming apparatus which operates in one of a plurality of power states including a low-power state, comprising: a reception unit that receives image data transmitted from an external device; an acquisition unit that acquires image data by reading a document; an image forming unit that executes a printing function of forming an image based on the image data received by said reception unit or a copying function of forming an image based on the image data acquired from said acquisition unit; a setting unit that sets a shift time until a power state of the image forming apparatus shifts to the low-power state after execution of image formation by said image forming unit; and a control unit that performs control, according to a first control mode, to: (a) shift the power state of the image forming apparatus to the low-power state upon the elapse of the set shift time after forming the image, via the printing function, based on the received image data, when the set shift time is greater than a predetermined time, (b) shift the power state of the image forming apparatus to the low-power state upon the elapse of the set shift time after forming the image, via the copying function, based on the acquired image data, when the set shift time is greater than the predetermined time, (c) shift the power state of the image forming apparatus to the low-power state before the elapse of the set shift time after forming the image, via the printing function, based on the received image data, when the set shift time is equal to or less than the predetermined time, and (d) shift the power state of the image forming apparatus to the low-power state upon the elapse of the set shift time after forming the image, via the copying function, based on the acquired image data, when the set shift time is equal to or less than the predetermined time.