Image processing apparatus for extracting representative characteristic from image data and storing image data to be associated with representative characteristic

Image data is displayed on an image display unit. An information input unit specifies a characteristic extracting range corresponding to the image data. An image-characteristic extracting unit extracts a representative characteristic from the specified range within the image data. The extracted representative characteristic are associated with the image data and stored in a storage device. The representative characteristic associated with the image data are also retrieved when retrieving the image data.