The TOCAI Description Scheme for Indexing and Retrieval 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.