[comp.graphics] Forwarded Report on Data Compression Conference 1991.

jk87377@cc.tut.fi (Juhana Kouhia) (05/20/91)

Forwarded from comp.compression
Original From: ross@spam.ua.oz.au (Ross Williams)
Original Summary: A personal account of the 1991 data compression conference
Original Keywords: data compression conference 1991 personal account
                   programme snowbird utah skiing patents
Date: 20 May 91 06:36:09 GMT

[Compressed version by Juhana Kouhia]


Data Compression Conference 1991 (DCC'91): The Unauthorized Report
==================================================================
Author : Ross Williams (ross@spam.ua.oz.au)
Date   : 20-May-1991.

ABSTRACT
--------
This document gives a personal account of the world's first conference
entirely devoted to  Data Compression: DCC91. The  conference was held
at Snowbird, Utah, USA, 7-11 April 1991.

CONFERENCE PROGRAM
------------------
[Selected items -Juhana]

1.  Image Coding by Adaptive Tree-Structured Segmentation
    X.Wu and C.Yao (U. Western Ontario)

2.  Prediction Trees and Lossless Image Compression
    N.D.Memon, S.S.Magliveras, and K.Sayood (U. Nebraska at Lincoln)

3.  Image Compression Methods with Distortion Controlled Capabilities
    T.Markas and J.Reif (Duke U.)

4.  Concentric-Shell Partition Vector Quantization with Application to
    Image Coding
    H.Nguyen and J.W.Mark (U. Waterloo)

5.  An Iteratively Interpolative Vector Quantization Algorithm for
    Image Data Compression
    K.Xue and J.M.Crissey (Wright State U.)

6.  A New Transform Domain Vector Quantization Technique for Image Data
    Compression in an Asynchronous Transfer Mode Network
    P.P.Polit and N.M.Nasrabadi (Worcerster Polytechnic Institute)

7.  A 64 Kb/s Video Codec using a 2-D Wavelet Transform
    A.S.Lewis and G.Knowles (Imperial College)

8.  A Practical Approach to Fractal Based Image Compression
    A.P.Pentland and B.Horowitz (MIT)

9.  New Methods for Lossless Image Compression Using Arithmetic Coding
    P.Howard and J.S.Vitter (Brown U.)

10. Complexity Aspects of Map Compression
    H.Brodlaender, T.F.Gonzales, and T.Kloks (UC Santa Barbara)

11. Compression of Natural Images Using Thread-like Visual Primitives
    J.Robinson (U. Waterloo)

12. A Neural Network Based VLSI Vector Quantizer for Real-Time Image
    Compression
    W.Fang, B.Sheu, and O.T.C.Chen (U. Southern California)

13. Two-Level Context Based Compression of Binary Images
    A.Moffat (U. Melbourne)

14. Flexible Compression for Bitmap Sets
    A.Bookstein (U. Chicago) and S.T.Klein (Bar Ilan U.)

15. Compression of Stereoscopic Image Data
    E.Salari an W.A.Whyte, Jr.

16. Concurrent Techniques for Developing Motion Video Compression Algorithms
    J.A.Elliott, P.M.Grant, and G.G.Sexton

17. Effects of Coefficient Coding on JPEG Basline Image Compression
    M.Chang and G.G.Langdon

18. Generalized Scanning and Multioresolution Compression
    I.Gertner and Y.Y.Zeevi

19. Implementing JPEG Algorithm on INMOS Transputer Equipped Machines
    A.Omodeo, M.Pugassi, and N.Scarabottolo

20. Improved Hierarchical Interpolation (HINT) Method for the Reversible
    Compression of Grayscale Images
    K.Chen and T.Ramabadran

21. Lossless Coding Techniques for Color Graphical Images
    G.S.Yovanof and J.R.Sullivan

22. Motion-Compensated Video Image Compression Using Luminance and
    Chrominance Components for Motion Estimation
    C.W.Wong

23. On the Selection of Color Basis for Image Compression
    W.K.Chau, S.K.Wong, X.D.Yang, S.J.Wan

24. Performance Analysis of a Vector Quantization Algorithm for Image Data
    A.Desoky and Y.You

25. Pictorial Data Compression Using Array Grammars
    E.T.Lee

26. Signal Processing and Compression for Image Capturing Systems Using a
    Single-Chip Sensor
    Y.T.Tsai

27. 3-D Image Compression for X-ray CT Images Using Displacement Estimation
    H.Less, Y.Kim, A.H.Rowberg, and E.A.Riskin

28. Transform Coding of Monochrome and Color Images Using Trellis Coded
    Quantization
    K.L.Tong and M.W.Marcellin

29. Using Fractal Geometry for Image Compression
    K.Culik and S.Dube

30. A Very High Speed Noiseless Data Compression Chip for Space
    Imaging Applications
    R.Anderson, J.Bowers, W.C.Fang, D.Johnson, J.Lee, and R.Nixon


PROCEEDINGS
-----------
As I understand it, the  conference proceedings have been published by
the IEEE and you can obtain a copy ("DCC91 proceedings") from:

IEEE Computer Society
PO Box 3014
10662 Los Vaqueros Circle
Los Alamitos CA 90720-1264
USA
Ph: +1 (714) 821-8380

The proceedings are in the form of a small, strongly bound book and is
essential reading  for compressor  heads. It may  also be  possible to
obtain a list of the papers presented and then individual reprints.



[I include this patent section in case it has something to do with
graphics -Juhana]


PATENTS
-------
One of the dominant underground themes of the conference (at least for
me) was  PATENTS. As Richard  Stallman has pointed out,  the situation
with software patents is getting on the stupid side. Amazing though it
is, there are now software patents covering:

   * Scrolling with multiple subwindows.
   * Exclusive OR highlighted text.
   * Natural order spreadsheet recalculation.
   * Use of backing store to store overlapping parts of windows.

These are just the beginning. Soon, it seems, it will be impossible to
write a large computer  program without accidentally violating several
dozen patents.

The field of  data compression is now hot with  patents. Starting with
the problems with LZW (Unisys wants about $20000 from any manufacturer
using it)  and Unix compress, we  have seen the LZ78  hierarchy almost
closed to the public. It is extremely unclear what is covered and what
is not.

A key issue here is that there  seems to be no TECHNICAL procedure for
establishing exactly what a software  patent covers. It seems that any
company that has a patent coming remotely close to an algorithm in use
can successfully launch (if not win)  a lawsuit against the user. This
environment rules  out the use  of any  algorithm close to  a patented
algorithm by  any company or individual  who could not survive  a test
law case. One result,  as we have seen, is the locking  up of the LZ78
hierarchy.

I went to the conference expecting to find the answers to the question
of  what is  covered  by patents  and  what is  not.  Instead I  found
hundreds of  people even  more confused  than I  was. In  the twilight
hours of the conference dinner I remember sitting at a table with some
fairly heavy compressor heads none of whom seemed to have the faintest
idea of what was covered by patents  - "Only a lawyer can decide" they
said.

From my communications before and during the conference my impressions
of the patent situation are as follows:

   * The LZ78 class is under challenge. Don't touch it until it is resolved.
     There was a rumour going around that a certain compressor head heavy
     had agreed to testify that prior art of LZW existed before Welch.
     But don't hold your breath.

   * The LZ77 class is basically open. However, there are patents popping
     up everywhere so get in early or you might find your algorithm gone.

   * Markov techniques (such as PPM, PPMC, DMC, DHPC, SAKDC, DAFC -- see
     my book for details) are all open. No problem. Go for it.

   * Arithmetic coding is open except for some binary arithmetic codes and
     some versions that avoid multiplication.

You can find out more about software patents and their problems from:

   The League for Programming Freedom
   1 Kendall Square #143
   PO Box 9171
   Cambridge MA 02139
   Net: league@prep.ai.mit.edu
   Phone: +1 (617) 243-4091
   Document: "Against Software Patents".
   Document: "Against User Interface Copyright".

To "raise the consciousness" of participants, James Woods and I handed
out  league for  programming freedom  propaganda and  buttons (reading
"Get Your  Lawyers off  My Computer").  We received  various responses
ranging from  that of someone  who seemed to  have just come  from the
live audience of the Arsenio Hall  show ("Hey yeah, give me that badge
- yeah,  wooo woo wooo, ooh  ooh ooh") to  the gruff refusal of  a guy
from a certain big company who  had probably come to the conference to
flog patent  licenses. Gruff refusals  were also obtained  from people
whom  we  had already  bothered  three  times  before  - its  hard  to
recognise the people you've already approached out of so many people!!

Most people at the conference seemed to agree that there was a serious
problem with  the patent situation  but did  not quite align  with the
League for  Programming Freedom whose  current short term goal  is the
elimination of  all software patents. Nevertheless,  it was gratifying
to see much  of the room wearing  the badges by the end  of the poster
session.



[Other interesting items in order of appearance -Juhana]


Break: 10:10-10:35
Lunch 12:40-4:00
Break: 9:40-10:05
Lunch 12:35-4:00
Break: 10:05-10:30
Lunch: 12:35-4:00
10:45am Break
1000-1015 Break
1215-1300 Lunch
====
I observed an  interesting effect during the (I  think) poster session
where  the hotel  served a  variety of  main-course snack  foods and a
chocolate cake cut up into slices.  The chocolate cake moved slowly at
first and then  was observed to vanish at  an exponentially increasing
rate. This could be because:

   1) Most people finished their "main course" and hit the chocolate cake
      at about the same time.
   2) Perceived worth increases with scarcity.

However, what I think was happening was that everyone had their eye on
the chocolate cake, but didn't want to eat any until they had finished
their "main course". However, when  the cake started disappearing, the
prospect of missing out caused lots of people to abandon this ideal in
favour of securing  some of the scarce resource. So  it was (2) with a
sort  of  added  criticality  thrown  in.  Maybe  we  could  use  some
catastrophe  theory  here.  Anyway,  it doesn't  matter  because  they
brought in another chocolate cake.

As a  general rule, the food  got better and better  as the conference
went on.
====



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Juhana Kouhia