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The FAQ (Frequently Asked Questions) for the groups comp.compression
and comp.compression.research is posted in comp.compression only.
This article is just a reminder, posted more frequently in both
groups. *Please* read the complete FAQ before posting in either group.

You can find the FAQ by searching for "comp.compression Frequently
Asked Questions" in the subject lines of group comp.compression.  If
the FAQ is no longer in this group, it should be in group news.answers
with the same subject line.

The FAQ is also available by anonymous ftp on rtfm.mit.edu [18.72.1.58]
in directory /pub/usenet/news.answers/compression-faq, files part1 and part2.

If you don't have FTP access, you can get the FAQ by a mail
server.  Send an email message to mail-server@pit-manager.mit.edu
containing the commands
    send usenet/news.answers/compression-faq/part1
    send usenet/news.answers/compression-faq/part2
For instructions, send an email message to the same address with the
words "help" and "index" (no quotes) on separate lines.


If you don't want to see this reminder regularly, please add the
subject line to your kill file.  If you have corrections or
suggestions for the FAQ, send them to Jean-loup Gailly <jloup@chorus.fr>.
Thank you.


Contents of the FAQ
===================

General questions:

[1]  What are these newsgroups about?
[2]  What is this .xxx file type?
     Where can I find the corresponding compression program?
[4]  What is an archiver?
[5]  What is the best general purpose compression program?
[7]  Which books should I read?
[8]  What about patents on data compression algorithms?
[9]  The WEB 16:1 compressor.
[11] What is the V.42bis standard?
[12] I need source for the winners of the Dr Dobbs compression contest
[13] I need source for arithmetic coding

Image and audio compression:

[15] Where can I get image compression programs?
[16] What is the state of the art in lossless image compression?
[17] What is the state of fractal compression?
[18] I need specs and source for TIFF and CCITT group 4 Fax.
[19] What is JPEG?
[20] I am looking for source of an H.261 codec.
[25] Fast DCT (Discrete Cosine Transform) algorithms
[26] Are there algorithms and standards for audio compression?

Common problems:

[30] My archive is corrupted!
[31] pkunzip reports a CRC error!
[32] VMS zip is not compatible with pkzip!

Questions which do not really belong to comp.compression:

[50] What is this 'tar' compression program?
[51] I need a CRC algorithm
[52] What about those people who continue to ask frequently asked questions?
[53] Where are FAQ lists archived?
[54] I need specs for graphics formats
[55] Where can I find Lenna and other images?

(Long) introductions to data compression techniques (part 2 of the FAQ)

[70] Introduction to data compression (long)
       Huffman and Related Compression Techniques
       Arithmetic Coding
       Substitutional Compressors
          The LZ78 family of compressors
          The LZ77 family of compressors

[71] Introduction to MPEG (long)
[72] What is wavelet theory?
[73] What is the theoretical compression limit?
[74] Introduction to JBIG

[99] Acknowledgments