Simple Worst-Case Optimal Adaptive Prefix-Free Coding

  title={Simple Worst-Case Optimal Adaptive Prefix-Free Coding},
  author={Travis Gagie},
  journal={2022 Data Compression Conference (DCC)},
  • T. Gagie
  • Published 7 September 2021
  • Computer Science
  • 2022 Data Compression Conference (DCC)
Suppose we want to store a string <tex>$S[1..n]$</tex> over an alphabet of size <tex>$\sigma$</tex> using adaptive prefix-free coding with fast encoding and decoding. If we are not too concerned about compression, we can process <tex>$/\mathrm{S}$</tex> in blocks of <tex>$\sigma$</tex> characters as follows: we encode or decode the first block with a Shannon code for the uniform distribution; to encode or decode the <tex>$ith$</tex> block, for <tex>$i > 1$</tex>, we build a Shannon code for the… 

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