To display attached information at least when the display matches the conditions regardless of a direct instruction from an operator in the case of displaying an image in which that attached information is embedded by electronic watermark processing.

Image information stored in an image storage means 106 is supplied to an attached information analytic means 112 and attached information is detected here. Besides, whether it is preset time or not is discriminated by a discriminating means 109 and at that time, a signal for permitting the display of the detected attached information is supplied to the attached information analytic means 112. The attached information analytic means 112 displays an image in which the attached information is embedded. Then, the attached information is controlled to be displayed only when a permission notice is supplied from the discriminating means 109.