This invention relates to an image processing apparatus and method for controlling output of a specific image, and a storage medium. For example, image data which is open to the public on the Internet may be printed out without permission by an ill-disposed person, even if it has a copyright. In this invention, when information indicating the presence of a copyright is stored in extended property information of image data, which complies with a hierarchical data format that hierarchically stores image data of a plurality of resolution, original image data, i.e., the image data of interest is controlled not to be output at a high resolution, thereby preventing original image data from being printed out without permission of the copyright holder.