This is a nice article posted on Codeguru.com by Sjaak Priester. In this article Sjaak uses octree color quantization to reduce a JPEG image with millions of colors down to a GIF with 256, as
well as giving you a look or two at Microsoft’s nice GDI+ API.

http://www.codeguru.com/gdi/qcolorquantizer.html

Current research projects in our lab include research into vector quantization (VQ), wavelets, image compression, edge detection using VQ, VQ for image browsing, VQ design for noisy channels, halftoning, and color palette management.

http://www.ee.washington.edu/research/dcl/

The University of Washington has a nice bibliography here, with pointers to books on Data Compression, VQ, Wavelets, and Information Theory.

http://www.ee.washington.edu/research/dcl/biblio.html

This page has source code for a couple of different VQ compression programs from the University of Washington’s EE Data Compression Labs.

http://www.ee.washington.edu/research/dcl/code/

This document clarifies aspects of colour specification and image coding that are important to computer graphics, image processing, video, and the transfer of digital images to print.

http://www.faqs.org/faqs/graphics/colorspace-faq/

This is billed as an introductory article with illustrations. I haven’t seen it - it requires free registration with this game development site. If you’re interested, please check it out and send me your thoughts.

http://www.gamasutra.com/features/20010416/ivanov_01.htm

This paper by Jyh-Han Lin and Jeff Vitter outlines new VQ algorithms based on linear programming. According to the abstract, the algorithm is the first known polynomial-time codebook design algorithm.

http://www.cs.duke.edu/~jsv/Papers/catalog/node67.html

Kluwer Academic Publishers, Boston Hardbound, ISBN 0-7923-9181-0 November 1991, 760 pp.

Please use
this link to purchase the book through Amazon.com. Your purchase will help support this web site.

http://kapis.www.wkap.nl/prod/b/0-7923-9181-0

Mohamed Qasem’s page dealing with VQ. A nice overview of what it’s all about, plus links to other sites and people in the VQ world.

http://www.geocities.com/mohamedqasem/vectorquantization/vq.html

by Allen Gersho and Robert M. Gray. This book shows up in at least one bibiblography, I would appreciate reviews from a reader.

http://www.amazon.com/exec/obidos/ASIN/0792391810/theinternetdatac

An audio compression format invented at NTT’s Cyber Space Laboratories. Get your player and compressor right here. (English avaible by following the sharp-eyed link.)

http://sound.splab.ecl.ntt.co.jp/

A short description of VQ by Nam Phamdo. Contains an animation which provides a nice picture of what actually happens in VQ.

http://www.data-compression.com/vq.html

This program by Nam Phambdo doesn’t have any declaration regarding use, so please contact the author before attempting to use it.

Reader Prabhu S. pronounced this program “Nice.”

http://www.data-compression.com/lbgvq.c

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 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

Paper by Christopher Chan, discussing quick and easy codebook development with VQ schemes.

http://citeseer.nj.nec.com/did/19447

Adaptive VQ describes a way to get asymptotically optimal results from VQ while adapting to changes in input statistics.

http://citeseer.nj.nec.com/fowler96adaptive.html

Vladimir has pointers to a batch of his papers here, which seem to concentrate on image compression, including VQ and Wavelet based compression. Plus many links to image compression, fractal, and wavelet pages.

http://www.cse.sc.edu/~culik/valenta/

Mary Holly Johnson wrote a couple of papers on something called ECVQ, which I’m guessing is a type of vector quantization. This ftp directory has a bunch of C code that probably implements the code from one or more of her papers.

ftp://isdl.ee.washington.edu/pub/VQ/mhjohns/

Antonio Ortega at USC has quite a few compression related papers on line. They include papers on wavelets and quantization.

http://sipi.usc.edu/~ortega/Papers.html

by P.C. Cosman, R.M. Gray, and M. Vetterli, IEEE Transactions on Image Processing, February 1996. They discuss using VQ in combination with subband and wavelet decompositions.

ftp://isl.stanford.edu/pub/gray/reports/subvq.ps

The comp.compression FAQ provides you with an answer to this question.

http://www.faqs.org/faqs/compression-faq/part2/section-7.html

by Keren O. Perlmutter, Sharon M. Perlmutter, Robert M. Gray, Richard A. Olshen, and Karen L. Oehler IEEE Transactions on Image Processing, February 1996). We investigate several VQ-based algorithms that seek to minimize both the distortion of compressed images and errors in classifying their pixel blocks.

ftp://isl.stanford.edu/pub/gray/reports/bayesvqip.ps

The NeuQuant Neural-Net image quantization algorithm (© Anthony Dekker 1994) is a replacement for the common Median Cut algorithm. It is described in the article Kohonen neural networks for optimal colour quantization in Volume 5, pp 351-367 of the journal Network: Computation in Neural Systems (Institute of Physics Publishing, 1994).

http://www.ozemail.com.au/~dekker/NEUQUANT.HTML