Logical formalization of multimedia interpretation

Nowadays, many documents in local repositories as well as in resources on the web are multimedia documents that contain not only textual but also visual and auditory information. Despite this fact, retrieval techniques that rely only on information from textual sources are still widely used due to the success of current text indexing technology. However, to increase precision and recall of multimedia retrieval, the exploitation of information from all modalities is indispensable, and high-level descriptions of multimedia content are required. These symbolic descriptions, also called deep-level semantic annotations, play a crucial role in facilitating expressive multimedia retrieval. Even for text-based retrieval systems, deep-level descriptions of content are useful (see, e.g., [7]).