Building a centralized database to process billions of open-ended queries per day is a mammoth undertaking. It appears that Google, who perhaps is the only company on the planet with enough imagination, incentive, and expertise to effectively build such a
Caliph & Emir are MPEG-7 based Java prototypes for digital photo and image annotation and retrieval supporting graph like annotation for semantic metadata and content based image retrieval using MPEG-7 descriptors.
The Calais web service automatically attaches rich semantic metadata to the content you submit. Using natural language processing, machine learning and other methods, Calais categorizes and links your document with entities (people, places, organizations,
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T. Vitvar, J. Kopecky, J. Viskova, and D. Fensel. Proceedings of the 5th European Semantic Web Conference, Berlin, Heidelberg, Springer Verlag, (June 2008)