Visitor's Talk



Semantic Compaction, Transmission, and Compression Codes

• Speaker: Ton Kalker, HP Labs (joint work with Frans Willems, Technical University Eindhoven)

• Abstract:
  In Bell Syst. Tech. J., 1948, Shannon wrote: "The semantic aspects of communication are irrelevant to the engineering problem." Indeed Shannon demonstrated that the information that is generated by a source depends only on the statistics of the source, and not on the meaning of the source output. By contrast with this we investigate here whether in a compaction system the codewords can be meaningful just like the source output sequences. We require the codeword to be close to the source sequence for some given distortion measure. For so-called semantic compaction systems we determine the fundamental limits for the i.i.d. case. Moreover we consider semantic transmission systems. These systems have the property that the codewords, i.e. the channel input sequences, are close to the source sequence. Finally we investigate semantic compression. A semantic compression system is actually a vector quantizer for which the codeword, i.e. the index to the reproduction vector, resembles the source sequence. Also for semantic transmission and semantic compression we determine the fundamental limits for the i.i.d. case.

• Biographical Sketch:
  Ton Kalker is a senior researcher at Hewlett-Packard Laboratories and a faculty member of the Technical University of Eindhoven. His primary responsibility is to support Hewlett-Packard in the area of media security, including watermarking, robust hashing, homomorphic encryption and Digital Rights Management.
  Ton received his Ph.D. degree from the University of Leiden in 1986. From 1983 until 1985 he was a faculty member of the University of Delft. From 1985 until 1994 he was member of staff at Philips Research in Eindhoven, where he developed currently widely deployed watermarking and fingerprinting solutions.
  Ton is a Fellow of the IEEE for his contributions to practical applications of watermarking, in particular watermarking for DVD-Video copy protection. He co-founded the IEEE Transactions on Information Forensics and Security.
  His other research interests include wavelets, multi-rate signal processing, motion estimation, psycho physics, digital video compression and medical image processing.