IN RECENT years, there has been a tremendous amount of activity in the area of indexing, search, retrieval and manipulation of multimedia data. A variety of techniques from various disciplines such as image and video processing, computer vision, audio and speech processing, statistical pattern recognition, learning theory and database research have been employed. Joint multimodal processing by combining multiple modalities such as audio, video, text etc., are also being used. This research, to a large extent, includes and goes beyond the activities of multimedia standards committees.

After the first IEEE International Conference on Multimedia & Expo (ICME) was held in New York City in August 2000, it was realized that the area of multimedia databases is one of the most active areas of research represented at ICME 2000. While there were other areas that emerged from the conference as important in their own rights, a decision was made by the editorial board of this transaction to organize and edit a special issue out of expanded versions of the better papers presented at ICME 2000 in the general area of what can be loosely described as multimedia database. To this end, a team of guest editors was assembled by maintaining a balance between the technical and geographical diversity in keeping with the composition of the editorial board of the IEEE TRANSACTIONS ON MULTIMEDIA and that of ICME, with Sankar Basu as the lead guest co-editor. Although the original intent was to solicit expanded versions of highly ranked papers from ICME 2000, a call for papers in the general area of multimedia databases was put out. Original papers were solicited in the general area of query, search, indexing, retrieval, and mining of structured and unstructured multimedia/multimodal information, including the areas of authentication and hiding of such data. Specific topics were to include, but were not limited to the following.• Query, search, indexing, retrieval and mining of multimedia information.