This J2ME (Java 2 Microedition) application allows mobile phones to send/receive compressed messages in a deflate format, optimized for short strings. It can achieve the ratio 1/2, i.e. two original messages are compressed in only one message. A recipient must have the similar application.
It costs $10.
Created: 28/01/2006
by Antonio SantagiulianaMore...
A bijective compressor using full size Rijndael encryption. BICOM is a freely available open source compressor. It uses a souped-up PPM algorithm, and is completely bijective.
Created: 01/11/2002
by Mark NelsonMore...
Most compression programs need to be able to do bit-oriented input and output. This is a problem, since most file systems are set up to do byte oriented I/O. Arturo Campos looks at ways to do an effective implementation of this neglected part of compression programming.
Created: 17/11/1999
by Mark NelsonMore...
Patrick Craig has an interesting tale to tell. Without being a data compression expert, he managed to beat the $5000 compression challenge. You won't see him taking an ocean cruise with his winnings, though. DCL reader commented: The challenge was obviously met.
Created: 25/04/2001
by Mark NelsonMore...
I'm pleased to announce with my co-authors availability of a preprint on our new algorithm to estimate the Shannon entropy rate (bits/symbol) or (bits/sec) of an observed sequence of low-alphabet symbols. It uses the Context-Tree-Weighting universal compression method, but doesnot use the compression ratio directly as an entropy estimator but as a scaffold for a Bayesian estimate. The result is significantly lower bias.
Created: 10/07/2004
by Mark NelsonMore...
NxServLiv allow compressed remote X sessions using NoMachine's NX oss libraries. Like ssh terminal but graphical. Work from Modem to Lan with different compression ratios
Created: 04/07/2004
by Mark NelsonMore...
Squashfs is a highly compressed read-only filesystem for Linux (kernel 2.4.x). It uses zlib compression to compress files, inodes and directories. Inodes in the system are very small and all blocks are packed to minimise data overhead. Block sizes greater than 4K are supported up to a maximum of 32K.
Release 2.0 of squashfs shipped in May, 2004.
Created: 31/05/2004
by Mark NelsonMore...
PDF documents are commonly used and their content is usually compressed. This article shows a simple C code that can be used to extract plain text from the PDF file.
Created: 31/05/2004
by Mark NelsonMore...
Java & MPEG-7 based tools for semantic annotation and retrieval of digital photos and images supporting graph like annotation and content based image retrieval.
Created: 23/05/2004
by Mark NelsonMore...
From Microsoft: This document describes Binary Delta Compression (BDC) technology and its use in software update deployment. This implementation of BDC technology developed by Microsoft reduces the download size of software update packages by downloading only the differences between old files and new files.
Created: 04/04/2004
by Mark NelsonMore...
DACT is a brute force compressor written by Roy Keene that tries out a whole library of compression routines on a given file, and then simply picks the best performer.
Release 0.8.36 was shipping in early March, 2004.
Created: 07/03/2004
by Mark NelsonMore...
A pre-compression transform by Przemyslaw Skibinski, somewhat along the lines of Star Encoding.
Version 3.0 of this program is shipping as of February, 2004.
Created: 01/02/2004
by Mark NelsonMore...
Compression is concerned with detecting patterns in order to reduce redundancy. Complearn is an attempt to take that pattern-recognition ability and use it for different ends.
Created: 18/01/2004
by Mark NelsonMore...
GAO Research sells modem software for quite a few different platforms, including a big batch of DSP parts. Naturally, this includes modules to perform both V.42bis and V.44 data compression.
Created: 21/12/2003
by Mark NelsonMore...
The LuraDocument.jpm PdfCompressor is a Windows application that can be used to automatically (Server version) or manually convert scanned documents to higly compressed PDF files. The supported input formats are TIFF, JPEG, BMP and PNM.
Created: 14/12/2003
by Mark NelsonMore...
A C++ hierarchy that is designed to efficiently read and write bit streams. Needless to say, this is quite useful for compression programs.
Version 1.0 shipped in December, 2003.
Created: 08/12/2003
by Mark NelsonMore...
Star Encoding performs some preprocessing on text files, enabling standard compressors to do somewhat better on the files. This article explains the transform and provides some sample code.
Created: 06/12/2003
by Mark NelsonMore...
This product advertises itself as a simple S3TC texture compression
tool. The description says that it loads an image file into your video card's RAM, then instructs the video card to compress it.
Created: 02/11/2003
by Mark NelsonMore...
This site appears to the home page for a project dedicated to developing an Open Source X Windows compression library.
Created: 14/10/2003
by Mark NelsonMore...
A general delta compression/differencing suite for any platform that supports autoconf/automake, written in C, w/ builtin support for reading,writing, and converting between multiple file formats.
Created: 28/09/2003
by Mark NelsonMore...
Free PDF Compressor that removes duplicate PDF objects, optionally takes advantage of new compression features of latest PDF specification (1.5), and optionally takes advantage of a new proposed format called "Compact PDF" that for many classes of documents compresses 30 - 60% better than what is possible in PDF 1.5.
Note: Navigate up two levels to get to Tom's download page.
Version 2.2 is shipping as of February, 2004.
Created: 12/09/2003
by Mark NelsonMore...
This cool program uses either Zip file or JPEG file to encrypt some of your data. I think it's free, email me if I'm wrong.
Created: 24/06/2003
by Mark NelsonMore...
This program is designed to accurately create a difference file between two packages, allowing for an update with a minimal source file.
Created: 19/06/2003
by Mark NelsonMore...
Soft Defender is a good exe file compressor, which can reduce the file size of 32-bit Windows programs by as much as 50%.In addition, Soft Defender is a perfect product of software protection of applications.With Soft Defender, your application can have anti-debugging, anti-tracer, anti-disassemble, anti-dumping, anti-apihook, file integrity checking functions in seconds. It requires no source code editing or your registration algorithm changing.
Created: 12/06/2003
by Mark NelsonMore...
This article on The Code Project web site shows you how to calculate a CRC, but even better it shows you how to create a file that will have a given CRC value.
Created: 07/06/2003
by Mark NelsonMore...
Convert your CHM help files from Microsoft to Adobe's PDF format. This is shareware that runs on Win32 platforms.
Created: 30/05/2003
by Mark NelsonMore...
This CodeProject article describes the development of a PATRICIA trie in the .NET framework. The actual code is written in C#, but naturally, it can be used with any of the .NET languages.
Created: 30/05/2003
by Mark NelsonMore...
This is a somewhat unique utility that will only be useful to those of you working on Visual Studio programming projects. Running it erases all your temporary project files, then zips up all the leftovers so you can backup your work.
Created: 26/05/2003
by Mark NelsonMore...
Links to code and tools to create random numbers. Quite useful, and includes some intriguing use of sound cards to provide true (instead of psuedo-random) numbers. Registration required.
Created: 23/04/2003
by Mark NelsonMore...
BitMagic is a C++ library that deals with dynamic bit vectors. It supports a couple of different ways to compress these bit vectors. This page discusses D-Gap Compression.
Created: 14/04/2003
by Mark NelsonMore...
BitMagic is a C++ library that deals with dynamic bit vectors. It supports a couple of different ways to compress these bit vectors. This page explains how to perform common operations on bit vectors while they are compressed in memory.
Created: 14/04/2003
by Mark NelsonMore...
Researchers looking for signs of life have decided that complexity might be a good indicator. What better to measure complexity than gzip?
Created: 31/03/2003
by Mark NelsonMore...
Somebody posting as thewhizkid complained to the comp.compression newsgroup that he just couldn't figure out how to do a CRC calculation. He got a couple of good pointers here, including one to the zlib code, and another including a bit of Java that could do the job. I'll add a pointer to my ancient-but-still-cogent article from DDJ,
File Verification Using CRC to the mix. Between the three choices, I hope the poster was able to get a handle on the mysterious CRC.
Created: 12/03/2003
by Mark NelsonMore...
Enbaya makes a product called ProGATE that is used to compress 3D graphics and animations for game developers.
Created: 05/03/2003
by Mark NelsonMore...
mod_zipvfs is an Apache2 module, that gives the httpd server the ability to read and browse zipped archives and allows traversal of their content like a virtual filesystem. It is very useful for browsing large html-based documentation without need of decompressing.
Created: 18/02/2003
by Mark NelsonMore...
WSQ by Aware is our implementation of the Federal Bureau of Investigation's Wavelet Scalar Quantization fingerprint compression standard. WSQ by Aware is the industry’s highest performing implementation of the FBI’s Wavelet Scalar Quantization (WSQ) digital fingerprint compression algorithm. WSQ is a wavelet transform-based compression standard, developed by the FBI for compression of digital fingerprint images.
Created: 13/12/2002
by Mark NelsonMore...
SEQUITUR is a method for inferring compositional hierarchies from strings. It detects repetition and factors it out of the string by forming rules in a grammar. The rules can be composed of non-terminals, giving rise to a hierarchy. It is useful for recognizing lexical structure in strings, and excels at very long sequences.
Created: 09/11/2002
by Mark NelsonMore...
Falk Hueffner created a dictionary program that was to be used for a Scrabble-type word game. The source can be found at this link under the name dawg.tar.gz.
Created: 30/10/2002
by Mark NelsonMore...
This paper describes a method which creates minimal acyclic deterministic FSAs. These can be used to create an efficient representation of a dictionary of words by merging identical subtrees.
Created: 30/10/2002
by Mark NelsonMore...
This instructive program creates a wide variety of 16 and 32 bit CRCs, many of which are commonly used in archiving programs. View the README in the same directory of the ftp server.
Created: 12/10/2002
by Mark NelsonMore...
DMSDOS is a loadable module for the Linux kernel. It provides read and write access to compressed FAT filesystems, such as Microsoft's Doublespace/ Drivespace and Stac's Stacker.
Created: 12/10/2002
by Mark NelsonMore...
jpg2html converts JPEG images into HTML. A series of jpg2html procedures are being written to explore different means and different effects.
Created: 12/10/2002
by Mark NelsonMore...
A format that can be used to send the differences between documents with some efficiency. This is part of a proposed extension to the HTTP standard.
Created: 29/09/2002
by Mark NelsonMore...
No documentation or hint of how this page was created, but it purports to give you some stats on the frequency of characters in English text.
Created: 28/09/2002
by Mark NelsonMore...
Squeezer is another executable compressor for Windows, and it's now free. Here's what you'll read on the Vidfern web site:
Vidfern Squeezer as the best file compressor, can squeeze executable files as well as text and HTML files. Get more space by squeezing your files! Squeezer is now free for personal and commercial use. It is fully functional, easy and powerful.
Reader Vali from the jp TLD said Thanks to all who create this real good product. I found it a very nice and easy compressor that supports exe, html and text files freely!
Created: 15/09/2002
by Mark NelsonMore...
CHAOS Self-Extractor is a utility program that creates self-extracting ZIP files for Windows. CHAOS supports a form of encryption that it claims is much stronger than standard Zip encryption.
Created: 09/09/2002
by Mark NelsonMore...
A search program for Win32 computers. ZipSearch knows how to look through Zip files and compressed EXEs to find search strings.
Version 1.07 shipping in December, 2002.
Created: 08/08/2002
by Mark NelsonMore...
This program lets you compress AutoCad DWG files into Zip archives for distribution.
Version 2.0 is shipping as of May, 2003.
Created: 08/08/2002
by Mark NelsonMore...
An article by Stephane Rodriguez on the CodeProject web site. Stephane describes his article as Revealing XML best practices with a utility tool and a framework. Yes, that means there is some sample code here as well.
Created: 21/07/2002
by Mark NelsonMore...
Lots of folks (including me) perform system backups into Zip archives. Over the years I became leery of proprietary formats used by various manufacturers of tape drives, removable disks, etc. Zip files give me a much better feeling, and make it a lot easier to browse through my backups. Martin Aignesberger must feel the same way, because he has created a product that performs daily backups into Zip files. This is a commercial product, but he does offer a 30 day free evaluation.
Created: 09/07/2002
by Mark NelsonMore...
Vcodex is a software collection for transforming data. Examples of data transformers include methods for compression/decompression, data differencing, encryption, etc. The source code distribution includes an implementation of Vcdiff using the framework.
Created: 02/06/2002
by Mark NelsonMore...
DevX published this nice piece describing bit oriented I/O in Java. This might not be directly related to Data Compression, but it is a requirement in nearly all data compression software. This site may require registration, I'm not sure.
Created: 29/05/2002
by Mark NelsonMore...
CNN reports on a research team at Cal Tech that has created a new algorithm for compressing 3D object representations. If you can figure out how it works from this article, send me an email!
Created: 29/05/2002
by Mark NelsonMore...
This document describes the Aurora Borealis algorithm, which combines statistical analysis with a back end using an unknown type of coding. Author Michael Asse seems to have high hopes for this technique.
DataCompression.info reader Viktor F. had this to say: This compression method is inefficient. LZW can beat this easily. The author should read some books about compression.
Created: 22/04/2002
by Mark NelsonMore...
This article is really about using the priority queue containers that are part of the standard C++ library. The example program implements a Huffman Encoder using the queues, showing how they can do a fairly complex piece of work without too much coding on your part.
Created: 12/04/2002
by Mark NelsonMore...
A directory of links and resources on compressing the 3D models used for computer graphics and other large geometric datasets. This is a replacement for the site at http://www.cc.gatech.edu/~kingd/3Dcompression.html.
Created: 11/04/2002
by Mark NelsonMore...
An article in Wired that talks about the use of compression for patten recognition. Tools as simple as Zip are able to accurately determine the language of a given text. More complex algorithms are being used to determine matches of DNA sequences.
Created: 11/04/2002
by Mark NelsonMore...
Rarissimo is a file utility to automatically compress and/or uncompress files, companion for the award winning compression program WinRAR. Distinguishable from other compression solutions by its ability to fully preserve NTFS alternate streams. This feature provides automatic compression/uncompression for Macintosh files stored on NT volumes preserving their filenames and peculiar structures - it means for example that you can use Rarissimo to send and receive Macintosh files using any standard FTP process (and not only Mac-based programs).
DataCompression.info user Marie M. said: This utility is very specialized so not easy to find. It is a great help to transfer Mac files without a special Mac ftp utility.
Created: 04/04/2002
by Mark NelsonMore...
A really nice set of links to people and resources related to pattern matching. This is a great general purpose page of links, but only lightly grazes the data compression world.
Created: 04/03/2002
by Mark NelsonMore...
This unique free program searchs through all your zip files looking for specific strings in specific file types.
Created: 04/03/2002
by Mark NelsonMore...
Bob talks about new codes that use more bits to compress the stuff you're looking at, and fewer bits for things on the sidelines.
Created: 02/03/2002
by Mark NelsonMore...
A couple of researchers from Rome have shown that adaptive compression algorithms can be used to accurately predict the language of the source text.
Created: 04/02/2002
by Mark NelsonMore...
Xdelta is a complete system for managing delta-compressed storage and network transport. Using the Xdelta system, you can easily incorporate this functionality into your application.
Created: 10/01/2002
by Mark NelsonMore...
ZFilter is the ZIP indexing filter for SharePoint, Internet Information Server, Site Server and Microsoft Exchange server. ZFilter is a library that handles .zip archives and returns indexable text and value properties in a similar way to the MS Office filter and the PDF filter supplied by Adobe. The library handles all zip archives created with WinZip, PKWare and DynaZip, indeed any archive created using the compression format based on PKWare.
Satisfied DataCompression.info user Jim R. had this to say:I've been searching high and low for exactly this thing for years, and now I've found it, and it works.
Created: 08/12/2001
by Mark NelsonMore...
This group aims to create a transfer protocol that has the functions of FTP and the advantges of HTTP. The main features will be encryption and compression. Work in progress - if you speak German you can learn more about the project
here.
Created: 18/11/2001
by Mark NelsonMore...
The Boost project is designed to put very high-quality peer-revied libraries in the hands of you and me. CRC checking has nothing to do with compression per se, but it is frequently used when archiving to validate results.
Created: 15/11/2001
by Mark NelsonMore...
This issue of the DDJ newsletter talks about bijective coding, a coding technique that is fearlessly promoted by David Scott, a regular presence in comp.compression.
Created: 11/08/2001
by Mark NelsonMore...
PackWord can compress a Microsoft Word document (.doc) file into a smaller, compressed, .doc file. The compressed .doc file is self-extracting: when loaded into Microsoft Word, the compressed document will automatically expand to the original version.
Created: 28/05/2001
by Mark NelsonMore...
The term bijective as used by Scott means that for any given given file X you are guarantted that A( B( X ) ) == B( A( X ) ) == X, where A and B are a pair of bijectively matched programs. In this particular case, A and B are a compressor and decompressor that use arithmetic coding. Includes C++ source.
Created: 01/05/2001
by Mark NelsonMore...
by Andrei Khodakovsky, Peter Schroder, Wim Sweldens. Compressing 3-D object representations is a good thing. Even better is allowing progressive display of these objects. The techniques in this paper are to be applied to geometric meshes.
Created: 08/09/2000
by Mark NelsonMore...
An overview of Shannon Fano coding from the folks at the DataCompression Reference Center.
This link points to an archived site, as the original has disappeared. Links on the archived page may or may not work properly.
Created: 30/08/2000
by Mark NelsonMore...
Juergen writes a lot of papers. Lots and lots of papers. Looks like lots of stuff on neural nets and the like.
Created: 01/08/2000
by Mark NelsonMore...
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.
Created: 17/07/2000
by Mark NelsonMore...
Douglas W. Jones, University of Iowa Department of Computer Science. This page contains some C source for a Splay Tree algorithm.
Created: 15/07/2000
by Mark NelsonMore...
This ftp site has copies of a number of papers by Christopher M. Brislawn. They include various ocuments on the FBI fingerprint compression standard, and a copy of the standard itself.
Created: 02/07/2000
by Mark NelsonMore...
Zlibc emulates a compressed file system. This lets you keep all your executables compressed in one place, unzipping them on the fly as they are needed. Looks like it works with various Linux and UNIX type sytems, including Solaris. I'm guessing that it's free, please correct me if I'm wrong.
Created: 03/06/2000
by Mark NelsonMore...
Woontack Woo has published quite a few papers dealing with coding and compression of stereo images. This is one of the few places you can find information on this somewhat esoteric subject.
Created: 09/04/2000
by Mark NelsonMore...
A console mode program that compresses CHW files. This is the type of file used in some help files distributed for Windows applications.
Created: 09/02/2000
by Mark NelsonMore...
IBM has developed a pair of Java clases that compress Unicode according to the Standard Compression Scheme for Unicode. Looks like they might be giving it away here.
Created: 28/12/1999
by Mark NelsonMore...
This master's thesis is available in PS format here. The abstract entry is in English, the Postscript document is in Spanish.
Created: 21/11/1999
by Mark NelsonMore...
JAM is a transparent hard disk compressor, which enlarges your disk space. With the JAM you will forget about annoying messages like 'Insufficient disk space...' with no need to purchase a new hard disk.
Created: 07/11/1999
by Mark NelsonMore...
Cognition as Compression, by Gerry Wolff, discussion of the author's research.
From as long ago as the last century it has been recognised that information processing in brains and nervous systems (perception, learning, thinking, neuro-muscular control etc) may be governed by principles of economy or compression.
Created: 07/11/1999
by Mark NelsonMore...
Computing as Compression: The SP Theory and the SP System, by Gerry Wolff, discussion of research in progress.
Created: 07/11/1999
by Mark NelsonMore...
This article contains the answers to some Frequently Asked Questions (FAQ) often seen in the USENET newsgroup comp.dcom.fax relating to facsimile standards, software, and hardware. Most importantly, contains an explanation of FAX encoding.
Created: 30/01/1999
by Mark NelsonMore...
This product lets you make the smallest PDF files possible, using compression supported by Adobe Acrobat Reader.
Created: 01/01/1970
by Mark NelsonMore...
bsdiff and bspatch are tools for building and applying patches to binary files. By using suffix sorting (specifically, Larsson and Sadakane's qsufsort) and taking advantage of how executable files change, bsdiff routinely produces binary patches 50-80% smaller than those produced by Xdelta, and 15% smaller than those produced by .RTPatch (a $2750/seat commercial patch tool).
Created: 01/01/1970
by Mark NelsonMore...
