首页> 外文期刊>IEEE Transactions on Information Theory >The empirical distribution of rate-constrained source codes
【24h】

The empirical distribution of rate-constrained source codes

机译:速率受限的源代码的经验分布

获取原文
获取原文并翻译 | 示例
           

摘要

Let X = (X/sub 1/,...) be a stationary ergodic finite-alphabet source, X/sup n/ denote its first n symbols, and Y/sup n/ be the codeword assigned to X/sup n/ by a lossy source code. The empirical kth-order joint distribution Q/spl circ//sup k/[X/sup n/,Y/sup n//spl rceil/(x/sup k/,y/sup k/) is defined as the frequency of appearances of pairs of k-strings (x/sup k/,y/sup k/) along the pair (X/sup n/,Y/sup n/). Our main interest is in the sample behavior of this (random) distribution. Letting I(Q/sup k/) denote the mutual information I(X/sup k/;Y/sup k/) when (X/sup k/,Y/sup k/)/spl sim/Q/sup k/ we show that for any (sequence of) lossy source code(s) of rate /spl les/R lim sup/sub n/spl rarr//spl infin//(1/k)I(Q/spl circ//sup k/[X/sup n/,Y/sup n//spl rfloor/) /spl les/R+(1/k)H (X/sub 1//sup k/)-H~(X) a.s. where H~(X) denotes the entropy rate of X. This is shown to imply, for a large class of sources including all independent and identically distributed (i.i.d.). sources and all sources satisfying the Shannon lower bound with equality, that for any sequence of codes which is good in the sense of asymptotically attaining a point on the rate distortion curve Q/spl circ//sup k/[X/sup n/,Y/sup n//spl rfloor//spl rArr//sup d/P(X/sup k/,Y~/sup k/) a.s. whenever P(/sub X//sup k//sub ,Y//sup k/) is the unique distribution attaining the minimum in the definition of the kth-order rate distortion function. Consequences of these results include a new proof of Kieffer's sample converse to lossy source coding, as well as performance bounds for compression-based denoisers.
机译:令X =(X / sub 1 /,...)是平稳的遍历有限字母源,X / sup n /表示其前n个符号,Y / sup n /是分配给X / sup n /的代码字通过有损源代码。将经验k阶联合分布Q / spl circ // sup k / [X / sup n /,Y / sup n // spl rceil /(x / sup k /,y / sup k /)定义为频率沿一对(X / sup n /,Y / sup n /)的k串对(x / sup k /,y / sup k /)的出现次数。我们的主要兴趣是这种(随机)分布的样本行为。令I(Q / sup k /)表示互信息I(X / sup k /; Y / sup k /)当(X / sup k /,Y / sup k /)/ spl sim / Q / sup k /我们表明对于速率/ spl les / R lim sup / sub n / spl rarr // spl infin //(1 / k)I(Q / spl circ // sup)的任何有损源代码k / [X / sup n /,Y / sup n // spl rfloor /)/ spl les / R +(1 / k)H(X / sub 1 // sup k /)-H〜(X)as其中H〜(X)表示X的熵率。这表明,对于包括所有独立且相同分布(i.i.d.)的大量源而言,这意味着。源和所有满足香农下限且均等的源,对于在渐近地达到速率失真曲线Q / spl circ // sup k / [X / sup n / Y / sup n // spl rfloor // spl rArr // sup d / P(X / sup k /,Y〜/ sup k /)为只要P(/ sub X // sup k // sub,Y // sup k /)是在k阶速率失真函数的定义中达到最小值的唯一分布。这些结果的后果包括基弗采样与有损源编码相反的新证明,以及基于压缩的降噪器的性能范围。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号