论文标题
不匹配的率延伸理论：合奏，边界和一般字母
Mismatched Rate-Distortion Theory: Ensembles, Bounds, and General Alphabets
论文作者
论文摘要
在本文中，我们考虑了使用代码簿进行编码的不匹配的率延伸问题，并且编码器根据与真实差异的不匹配的失真函数选择最小截止性代码字。对于离散无内存源的情况，我们使用多用户编码技术（即叠加编码和消除并行的平行编码）建立可实现的率延伸界限。我们研究了这些实现匹配的利率差异权衡的示例，但是具有独立代码字的标准合奏并没有这样做。另一方面，与频道编码对应物相比，我们表明在某些情况下，结构化的随机代码手册可以比非结构化对应物更糟。此外，鉴于将现有结果和上述结果适应一般字母的困难，我们认为更简单的I.I.D.随机编码集合，并为一般字母建立其可实现的率延伸界限。
In this paper, we consider the mismatched rate-distortion problem, in which the encoding is done using a codebook, and the encoder chooses the minimum-distortion codeword according to a mismatched distortion function that differs from the true one. For the case of discrete memoryless sources, we establish achievable rate-distortion bounds using multi-user coding techniques, namely, superposition coding and expurgated parallel coding. We study examples where these attain the matched rate-distortion trade-off but a standard ensemble with independent codewords fails to do so. On the other hand, in contrast with the channel coding counterpart, we show that there are cases where structured random codebooks can perform worse than their unstructured counterparts. In addition, in view of the difficulties in adapting the existing and above-mentioned results to general alphabets, we consider a simpler i.i.d. random coding ensemble, and establish its achievable rate-distortion bounds for general alphabets.
