April 2020
Intermediate to advanced
210 pages
4h 47m
Chinese
Content preview from 数据压缩入门
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2
｜
第
1
章
（
variable-length codes
，
VLC
）、
统计压缩
（
statistical compression
）、
字典编码
（
dictionary
encodings
）、
上下文模型
（
context modeling
）和
多上下文模型
（
multicontext modeling
）。 所
有这
5
类算法都有很多变种，这是一件好事，因为我们可以根据自己的需要来选择。每类
算法的变种在输入数据、算法性能、内存要求以及输出大小方面存在细微的差别。要选出
其中最佳的一个算法，需要在准备的数据上测试这些算法，然后找出压缩效果最好的那个。
这几类算法也可以混合使用，因为其中有些算法的目的就是转换数据，使得其他的算法在
压缩时更有效。
如果想成为数据压缩方面的专家，那么你就必须理解这几类算法、如何搭配使用它们，以
及对于特定的数据集需要从哪类算法中选出一个具体的算法。
下面我们开启学习之旅吧。
1.2
惹人
“
愤怒
”
的克劳德
•
香农
让我们先回到
20
世纪
40
年代，一位名叫克劳德
•
香农的统计学家发表了好几篇论文，详述
了他在第二次世界大战期间在军队任职时以及之后在贝尔实验室工作时所做的研究工作。
香农非常聪明，数学学得特别好。在
1936
年离开密歇根大学之前，他已经取得了工程技术
学士学位和数学学士学位。随后，他又去了麻省理工学院，并在那里做了很多研究工作。
他的硕士论文题为《继电器与开关电路的符号分析》，该论文为基于开关的现代电路计算
奠定了基础。
1948
年，香农又发表了《通信的数学理论》，在这篇论文中他详细论述了发送者怎样对要 ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.