English

Variable-Length Lossy Compression Allowing Positive Overflow and Excess Distortion Probabilities

Information Theory 2018-12-17 v2 math.IT

Abstract

This paper investigates the problem of variable-length lossy source coding allowing a positive excess distortion probability and an overflow probability of codeword lengths. Novel one-shot achievability and converse bounds of the optimal rate are established by a new quantity based on the smooth max entropy (the smooth R\'enyi entropy of order zero). To derive the achievability bounds, we give an explicit code construction based on a distortion ball instead of using the random coding argument. The basic idea of the code construction is similar to the optimal code construction in the variable-length lossless source coding. Our achievability bounds are slightly different, depending on whether the encoder is stochastic or deterministic. One-shot results yield a general formula of the optimal rate for blocklength nn. In addition, our general formula is applied to asymptotic analysis for a stationary memoryless source. As a result, we derive a single-letter characterization of the optimal rate by using the rate-distortion and rate-dispersion functions.

Keywords

Cite

@article{arxiv.1701.01800,
  title  = {Variable-Length Lossy Compression Allowing Positive Overflow and Excess Distortion Probabilities},
  author = {Shota Saito and Hideki Yagi and Toshiyasu Matsushima},
  journal= {arXiv preprint arXiv:1701.01800},
  year   = {2018}
}
R2 v1 2026-06-22T17:43:27.733Z