Publikationen

The amount of information available on the internet and within enterprises has reached an incredible dimension.Efficiently finding and understanding information and thereby saving resources remains one of the major challenges in our daily work. Powerful text analysis methods, a scalable faceted retrieval engine and a well-designed interactive user interface are required to address the problem. Besides providing means for drilling-down to the relevant piece of information, a part of the challenge arises from the need of analysing and visualising data to discover relationships and correlations, gain an overview of data distributions and unveil trends. Visual interfaces leverage the enormous bandwidth of the human visual system to support pattern discovery in large amounts of data. Our Knowminer search builds upon the well-known faceted search approach which is extended with interactive visualisations allowing users to analyse different aspects of the result set. Additionally, our system provides functionality for organising interesting search results into portfolios, and also supports social features for rating and boosting search results and for sharing and annotating portfolios.

Retrieval in current multimedia databases is usually limited to browsing and searching based on low-level visual features and explicit textual descriptors. Semantic aspects of visual information are mainly described in full text attributes or mapped onto specialized, application specific description schemes. Result lists of queries are commonly represented by textual descriptions and single key frames. This approach is valid for text documents and images, but is often insufficient to represent video content in a meaningful way. In this paper we present a multimedia retrieval framework focusing on video objects, which fully relies on the MPEG-7 standard as information base. It provides a content-based retrieval interface which uses hierarchical content-based video summaries to allow for quick viewing and browsing through search results even on bandwidth limited Web applications. Additionally semantic meaning about video content can be annotated based on domain specific ontologies, enabling a more targeted search for content. Our experiences and results with these techniques will be discussed in this paper.