Research :: Information Theory
Principal investigator: Prof Charalambos D. Charalambous
Co-investigator: Themistoklis Charalambous
Lossless fixed to variable length source codes are usually examined under known source probability distributions, and unknown source probability distributions. For known source probability distributions there is an extensive literature which aims at minimizing various pay-offs such as the average codeword length, the average redundancy of the codeword length, the average of an exponential function of the codeword length, the average of an exponential function of the redundancy of the codeword length. On the other hand, universal coding and universal modeling, and the so-called Minimum Description Length (MDL) principle are often examined via minimax techniques, when the source probability distribution is unknown, but belongs to a pre-specified class of source distributions.
With respect to the above pay-offs Shannon codes find sub-optimal code lengths by treating them as real numbers, while Huffman codes find the optimal code lengths by treating them as integers. Although Shannon codes are over the years investigated for a variety of pay-offs, optimal Huffman codes are available only for a limited number of pay-off functions.
This work is concerned with lossless coding problems, in which the pay-offs are general and they encompass as a special case several pay-off criteria investigated in the literature, while certain relations to universal coding are also delineated.
Conference papers:
| [1] | Themistoklis Charalambous, Charalambos D. Charalambous and Farzad Rezaei : "Lossless Coding with Generalized Criteria", in the IEEE International Symposium on Information Theory (ISIT), July 2011. Abstract | arXiv | Presentation: PDF |
