The ToCAI description scheme for indexing and retrieval of multimedia documents

A framework, called Table of Content-Analytical Index (ToCAI), for the content description of multimedia material is presented. The idea for such a description scheme (DS) comes out from the structures used for indexing technical books (containing a Table of Content, typically placed at the beginning of the book, where the list of topics is organized hierarchically into chapters, sections, and an Analytical Index, typically placed at the end of the book, where keywords are listed alphabetically). The ToCAI description scheme provides similarly a hierarchical description of the time sequential structure of a multimedia document (ToC), suitable for browsing, and an "Analytical Index" (AI) of audio-visual key items for the document, suitable for effective retrieval. Besides two other sub-description schemes are proposed to specify the program category and the description of other metadata associated to the multimedia document in the general DS. The detailed structure of the DS is presented by means of a UML diagram. Moreover, some suitable automatic extraction methods for the identification of the values associated to the descriptors that compose the ToCAI are presented and discussed. Finally, a browsing application example is also proposed.