Image representations for access and similarity-based organization of web information

Although digital and visual technologies are beginning to converge, most digital systems continue to use text to access and organize information. Textual organizations, such as indexes and conceptual hierarchies, are effective for well-structured information, but seem less effective for vast and poorly-structured sources like the World Wide Web, where information exists in a wide range of formats, styles, and combinations. Images provide a complementary way to represent information that may be better suited for helping people use large poorly-structured information sources. Images are perceived quickly, even when reduced in size. Animation, scaling, and layout techniques can therefore help people access masses of visual information with minimal cognitive overhead. Because images play a special role in the function of human memory, hypermedia systems that use images as links to information may be less susceptible to the classic hypertext problems of spatial disorientation and cognitive overhead. Mandala is a platform for studying the utility of images for accessing and organizing web information. Mandala lets people view hundreds of thumbnails of web page images. Selecting any thumbnail signals a web browser to display the associated page. Other systems that use images to represent information focus on server-side applications, because images can take a long time to retrieve over the web. Mandala focuses on client-side applications and minimizes retrieval delays by obtaining images from a proxy server cache. Given a collage of images, people have an intrinsic ability to identify groups of related images quickly. Mandala is designed to make it easy for people to share their visually-identified groups with the system by dragging and dropping thumbnails between windows. Mandala also groups different types of images automatically, computes layouts for groups, and stores groups as imagemaps. With these capabilities, Mandala is, at once, a repository for visual site indexes, a visual history facility, a visual bookmark facility, and a cache visualization application. In addition to helping people access and organize information, Mandala's visualizations can increase cache hit-rates and provide shared access to relevant resources, while revealing the dynamic access patterns of a community.