In accordance with an embodiment, an image processing apparatus comprises a human sensor, a fixing device and a controller. The human sensor detects a person in the vicinity of the image processing apparatus. The fixing device carries out fixation of an image formed with a decolorable recording agent serving as a recording agent containing a coloring agent which is decolored through heating on a medium and decoloration of the image formed on the medium. The controller controls the fixing device to stop the decoloration of the image when the person is detected by the human sensor.