How much can a given piece of data be compressed? This FAQ addresses that question, including some necessary critiques of the question itself. Graham Fyffe apparently spends some time thinking about complexity.

http://www.geocities.com/CollegePark/9315/infofaq.htm

A set of slides, apparently for a course talking about data compression.

http://www.cdt.luth.se/~johnny/courses/smd074_1999_2/CodingCompression/kap28/slide0.html

A huge selection of compression source and executables for the enigmatic Amiga.. I don’t know if this is a mirror site or independent.

ftp://us.aminet.net/pub/aminet/util/pack/

UB Video says:

UB Video Inc., based in Vancouver, Canada, is a leading provider of coding and transcoding software solutions for video communications. UB Video provides software products that run on desktop PCs as well as on programmable Digital Signal Processors and Media Processors. UB Video’s products include:

Encoders/Decoders

http://www.ubvideo.com/

A couple of programs using neural networks for compression, along with a couple of papers by the author. This area of data compression is definitely underserved, check out what’s here and see if neural networks deserve more attention than they are getting.

Update: This page appears to now have some links to general lossless benchmarking info.

http://cs.fit.edu/~mmahoney/compression/

Douglas W. Jones, University of Iowa Department of Computer Science. This page contains some C source for a Splay Tree algorithm.

http://www.cs.uiowa.edu/~jones/compress/

A paper by Andrej Brodnik and Svante Carlsson. A data structure that lets you decode Huffman streams super-duper quick.

ftp://www.ijp.si/pub/preprints/ps/98/pp600.ps

The home page of the MUSICompress lossless compression method.

http://hometown.aol.com/sndspace/index.html

A project at Cambridge University that led to a low bit rate speech coder that was used in the HP 620LX Palmtop PC.

http://svr-www.eng.cam.ac.uk/~ajr/speechCoding.html

A company that speciailizes in providing compression technology to other companies.

http://www.ictcompress.com/

Apple’s Quicktime page. Get it here.

http://www.apple.com/quicktime/

One of the many academics interested in data compression at University of Waikato in New Zealand. Cleary has been involved in many important developments in the field.

http://www.cs.waikato.ac.nz/Staff/john-g.-cleary.html

The Signal Processing and Coding Laboratory (SPACL) at The University of Arizona has some papers on line, plus some information on their current projects. They seem to be interested in wavelets, quantization, and signal coding.

A DCL reader complained: Very little useful information on the website. On topic, but not helpful at all.

http://www-spacl.ece.arizona.edu/

A straightforward discussion of Huffman compression. Written at a level so that it can be understood without much experience in data compression or programming.

http://home.ecn.ab.ca/~jsavard/crypto/mi0601.htm

Cisco talks a bit about new products using V.44 compression licensed from Hughes Network Systems. A few claims, not much in the way of facts.

http://www.cisco.com/warp/public/146/pressroom/2000/jul00/sp_071100.htm

This is a recurring theme in comp.compression, which I call “The Magic Function Theory.” It sounds like a good idea, but analysis shows that it won’t work.

http://www.dogma.net/markn/FAQ.html#Q19

Earth Etc. makes a free wavelet based compressor that somehow ties in with their web server product. In theory they supply plugins that you can use to view the compressed images.

DCL reader JJB had this to say: Limited in size and other features in the free version as well as limited documentation in the free version, but decent examples if you can learn from those (you just can’t learn what they don’t show there). Very specific to Geo-Spacial images (satelite images and the like), decent compression, speed and recovery of all sizes equal to or less than original (use power of 2 sizes for best results)..

http://www.earthetc.com/iws/Products/dataprep/ecwcompress_text.htm

The ITU has officially adopted the v.44 standard, which is starting to ship in mid-2001 on modems supporting the v.92 standard. V.44 uses a compression algorithm known as LZJH, which was invented by Jeff Heath and is owned by Hughes Network Systems. According to Jeff, ITU testing showed that V.44 was 20% to 60% better than V.42bis on
typical internet web downloads.

http://www.itu.int/newsroom/press/releases/2000/14.html

A paper by Sebastian Deorowicz appears here, which claims to make improvements in efficiency to BWT compression, giving the best ratios of any BWT program on the Calgary Corpus.

http://www-zo.iinf.polsl.gliwice.pl/~sdeor/pub/deo00.ps

PhD thesis by Franck Davoine, 20 December 1995. The key to a good fractal compression algorithm is the method by which it breaks down segments of an image into smaller pieces, called partitioning. Davoine introduces a partitioning method based on Delaunay triangulation.

ftp://ftp.imag.fr/pub/Mediatheque.IMAG/theses/95-Davoine.Franck/notice-anglais.html

Home of the WaveStat algorithm, which appears to be a fairly conventional wavelet-based image compressor. Links on this page to a paper describing the technique, but no code as far as I can tell.

http://www.mabuse.de/noframe/wavestat_nf.html

Links to several publications related to data compression and pattern matching.

http://sequence.rutgers.edu/~nevill/

Wil Osberger has published a bunch of papers dealing the perceptual image assessment. You can see most of them here. While this isn’t strictly a compression topic, it is obviously of critical importance to lossy compression techniques.

http://web.archive.org/web/20010428062527/http://www.scsn.bee.qut.edu.au/~wosberg/pub.htm

Peter Cherriman’s page on H.263 coding, includes information, pointers, and a couple of demo sequences.

http://rice.ecs.soton.ac.uk/peter/h263/h263.html

Peter Cherriman’s page on H.261 coding, includes information, pointers, and a couple of demo sequences.

http://rice.ecs.soton.ac.uk/peter/h261/h261.html

A big selection of the published papers of Peter Cherriman, concentrating on H.26x coding and other low bit rate video techniques.

http://rice.ecs.soton.ac.uk/peter/publications/publications.html

Pointers to a variety of wavelet codecs. I believe all the codes presented here are non-commercial software.

http://www-nt.e-technik.uni-rostock.de/~ts/Software/download.html

I don’t know if Hamarsoft is still in business, but you can still get a copy of HAP here. Harald Feldmann was Hamarsoft.

http://www.xs4all.nl/~feldmann/

A bibliography of Pamela C. Cosman’s papers, with links to many that are available on line. Many papers on wavelet-based and VQ image compression, along with a few miscellaneous others.

http://code.ucsd.edu/pcpapers.html

A paper describing the use of neural networks to do image compression.

http://www.ee.duke.edu/~cec/research/neuralcompression/JPL/paper.html