The Great Lempel-Ziv vs. Arithmetic Coding Debate

In order to do something different the next class will be arranged in the form of "The Great Lempel-Ziv vs. Arithmetic Coding Debate". Therefore participation to this class is obligatory except for a very good reason that should be mailed beforehand to Tomi and Petri. This debate will take place on Thursday February 17th from 4:00PM-6:30PM at HIIT premises (HTC Ruoholahti, Tammasaarenkatu 3). The front door closes at 16:00, so if you come late, call Petri (040 553 1162). Inside the "Pinta" building, take the elevator to the 6th floor, turn right, and use the door buzzer to get in. Right after the door there is a small table with a list of participants: add your signature next to your name.

For the debate, half of the groups will be defending the use of arithmetic coding and the rest universal coding based on Lempel-Ziv coding. The point is to argue about the use of the methods from pragmatic point of view, i.e., why in practice one should prefer one method over the other. The debate will be structured as follows:

1) The defending groups will select among themselves people to give a brief 10 minute introduction (2-3 transparencies) to the method in question.

2) Both parties will present a list (5 items or more) of reasons why their method is better than the competing one.

3) A discussion will be intiated and hopefully lively continued.

There will be pizza and (soft) drinks available and the winners get even more pizza. The group assignments are as follows, and will not be changed without strong supporting argumentation:

Team Lempel-Ziv:

Jarmo Ahosola (chair)
Janne Kataja
Jaakko Saaristo
Sampo Etelävuori
Reima Halmetoja
Esa Junttila
Sampo Yrjänäinen
Mikko Heilimo
Ilari Nieminen

Team Arithmetic coding:

Urho Konttori (chair)
Toni Merivuori
Antti Nyberg
Mika Lampi
Olli Lyytinen
Esa-Matti Miettinen
Eerika Savia
Margus Lukk
Tuomas Koskimies

Good starting points as reading material for the debate can be found in

ť MacKay's draft, Chapter 6
ť Lempel-Ziv in: Loben Chiang's thesis draft
ť data-compression.com: Lossless Data Compression
ť Steve Blackstock: LZW and GIF explained
ť Arturo San Emeterio Campos: Arithmetic coding
ť Mark Nelson: Arithmetic Coding + Statistical Modeling = Data Compression (Dr. Dobb's Journal, Feb. 1991)




3 Concepts: Information	2005