Some image compression tests by Mike Muus, the author of ping.

http://ftp.arl.army.mil/~mike/bermuda/

Unlike some other compressor comparison sites, I won’t be looking for a compressor offering for the last bit of compression. Instead I’ll try to find the most practical compressor out there.

http://www.elis.ugent.be/~wheirman/compression/

This site compares compressors on the basis of compression ratios only. Speed is not an issue.

http://www.freewebs.com/emilcont/

A rating of roughly 20 different compressors - strictly based on size.

http://members.optushome.com.au/dogg01/compframe.htm

A nice set of tests comparing a wide variety of executable packers.

http://pect.y11.net/

A little short on docs here, but from the title we’d have to guess that John De Bock compresses the source code for the GIMP and lists the results.

http://studwww.ugent.be/~jdebock/gimp_source_compression_test.htm

From the site: Epic24 is a GUI program that I wrote to interactively compare graphic compression codecs against each other. It currently contains JPG, Lossless JPG, JPEG 2000, (Jasper Library Implementation), PNG, John Robinson’s BTP and ATP, and finally my own lossless graphics compression called IMPLODE (IMage Predictive LOssless Decoder Encoder).

http://www.users.bigpond.com/kevinpeirce/Epic24/index.htm

Miracle video encoding technology verified by this Australian testing firm.

http://www.tollygroup.com/TS/2003/MediaWorldCom/AdamsPlatform/TollyTS203125MediaWorldOctob
er2003.pdf

Werner Bergmans has created a new benchmark site that aims to show the best compression ratios possible for multiple file types, including English text, executables, graphics, and so on. Werner says he is running these tests with 80-100 programs for each file type!

Reader Werner B. says Useful site to compare results of different compression programs. Regularly updated.

http://www.maximumcompression.com/

Roberto Amorim is a familiar and friendly presence on the Hydrogen Audio board. This link points to the many audio compression listening tests he has conducted. These include evaluations of AAC and MP3 encoders at a rew different rates.

http://www.rjamorim.com/test/

Comparisions of over 230 archivers, in handy Excel format, from Berto.

Reader Emiliano C. said “Wonderful! Great! Wonderful! Cool!”

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

The folks at LIVE conducted a subjective test of images at various compression levels, and have made the results available here. The images and results are both available here.

http://live.ece.utexas.edu/research/quality/

PC Magazine used a jury to compare the codecs used in several popular media players, with interesting results.

http://www.pcmag.com/article2/0,4149,815424,00.asp

A set of benchmark results that compare various versions of LHA and jLHA. (jLHA is an LHA library found on the same web site.)

http://homepage1.nifty.com/dangan/en/Content/Program/Java/jLHA/LhaBenchmark.html

Josh Taylor of ZDNet did a quickie informal comparison of the new Windows Media 9 format and gives it a thumbs-up.

http://www.zdnet.com/anchordesk/stories/story/0,10738,2879818,00.html

This German news item reports on a test that pitched Ogg Vorbis against MP3, Window Media, AAC, and RealAudio. My Babelfish translation says In particular with 64 kBit/s Ogg Vorbis could convince and left the entire prominent competition behind itself. I think that means it won!

http://www.heise.de/newsticker/data/anw-08.09.02-000/

This web site aims to provind blind quality testing of sound codecs. The site is just being launched at this time (3/2002), and is currently testing eight codecs.

Update: As of 8/2002, a few new codecs were added to the test suite: Ogg Vorbis 1.0, MPEG-4 Audio for QuickTime, and the PsyTel MPEG-4 AAC codec.

http://www.soundexpert.info/

A great discussion of audio compression, which includes the results fo the 64 Kbps listening test.

http://ff123.net/

Yoockin Vadim has a page here with ratings of 10 popular lossless compressors.

http://compression.graphicon.ru/ybs/best.htm

ACT - by Jeff Gilchrist. ACT is the Archive Comparison Test, a long running benchmark on well known archiving programs. Lots of good updates in May of 2002.

http://compression.ca/

This directory contains source and executable for Charles Bloom’s PPMZ encoder, as well as a paper on PPMZ and some benchmark results. There are also links to a few other pages containing PPM information.
News: Charles Bloom has now released the source code to PPMZ2. He says it is both cleaner and faster than the original PPMZ code.

http://www.cbloom.com/src/ppmz.html

Ross Arnold and Tim Bell, “A Corpus for the Evaluation of Lossless Compression Algorithms”, Proc. IEEE Data Compression Conference, Snowbird, Utah, March 1997.

http://www.cosc.canterbury.ac.nz/~tim/corpus/report.ps.gz

A study at the University of Florida showed that even mildly compressing coronary angiograms led to an increase in diagnostic errors.

http://www.eurekalert.org/pub_releases/2000-05/UoF-Itda-3105100.php

The author of this page clearly has a bone to pick with some of the MP3 decoders out there. From the site: This site contains test results on a number of mp3 decoders. Such a test wouldn’t be necessary if all decoders worked properly, but unfortunately they don’t. In fact the outputs of many popular decoders were found to be incorrect. .

http://web.archive.org/web/20020124200304/http://privatewww.essex.ac.uk/~djmrob/mp3decoder
s/intro.html

A set of subjective tests of various encoders.

http://fastforward.iwarp.com/1400.html

Real takes a whack at their chief competitor, Microsoft. Looks like they put some time and effort into this.

http://www.real.com/msaudio/

Zarak Systems will perform Quality of Service testing using PSQM, the Perceptual Speech Quality Measurement. This web page will tell you a little bit about what that means to you.

http://www.psqm.com/

A comprehensive set of tests on lossless data compression.

http://geocities.com/eri32/

My particular interest is in delivery of music via the Net - with compression which does not affect the sound quality at all. I am primarily interested in compression ratios, not speed of the programs. I think this is the first web site devoted to listing all known lossless audio compression algorithms and software - please email your suggestions and I will try to keep it up-to-date.

http://www.firstpr.com.au/audiocomp/lossless/

A comparison of various lossy audio compression schemes. Panos Stokas provides his take on the whole situation, and includes tons of links to files, articles, and more food for thought. Most readers seem to like this web page, but one reader had this negative comment: This website is patently and fatally flawed to the nth degree. Nothing but misconception and conjecture with no real basis in scientific analysis. Very misleading to the uneducated in audio compression.. Another reader says Just reading “However, we have not found a single implementation that did not produce serious amounts of distortion in our testing sample. Nobody seems interested any longer.” about AAC of all things, makes it apparent that this guy has no idea what he’s talking about or what he’s doing.

http://ekei.com/audio/