A light emitting device (10) includes a light emitting part (11) and a control part (13) for controlling repeated turning on and off of the light emitting part every unit time period set in advance in accordance with a data pattern representing identification data for identifying people wearing the light emitting device (11). An image processing device (20) includes an image acquiring unit (21) for acquiring images including the light emitting device captured using a camera (200), a read-out unit (23) for reading out the data pattern on the basis of the turning on and off of the light emitting part included in the light emitting device included in the acquired images, a data acquiring unit (24) for acquiring the identification data represented by the read out data pattern, and an image processing unit (25) for adding the acquired identification data close to the light emitting device included in the acquired image. The turning on and off of the light emitting section is not continuous in the data pattern.
