When an accepting section 102 accepts an order to acquire image data, an image data acquirer 104 acquires image data from a memory section 130 and compresses it in the JPEG format. An orientation identifier 122 identifies orientation information of an image processing device 10 by using a detection value of an acceleration sensor. A direction identifier 124 identifies the azimuthal angle of a lens optical axis by using a detection value of a geomagnetic sensor and orientation information identified by the orientation identifier 122. If it is determined by the orientation identifier 122 that the image processing device 10 is in a horizontal orientation, the direction identifier 124 identifies the azimuthal angle of the lens optical axis from a predetermined direction in the image processing device 10 and the detection value of the geomagnetic sensor without using the lens optical axis direction.