Abstract
Mobile devices represented by smart phones are being widely popularized in the world. Among many interesting functionalities and applications of mobile devices, the camera function and image viewer application may be most frequently used by everybody, and consequently a usual person may have more than a thousand of images in his smart phone. However, it is very difficult to find an image that users want to see since they have to scan most thumbnails. Furthermore, in mobile devices, it is not easy or not possible for users to make subdirectories. In order to resolve this problem, we propose and implement a semantic directory service for image gallery on mobile devices. By dynamically providing multi-level semantic directories on image gallery, users can find the image they want to search.