data compression link collection


zlib is a freeware multiplatform compression library written in highly portable C. zlib implements the deflate algorithm used by PKZip, which means it can be used as the compression engine for Zip compatible archivers. It has also found use as the standard compressor in quite a few other products, and is rightly hailed as a wonderful piece of work.

Ch zlib Package

Ch zlib Package is Ch interface to zlib. Ch is a C/C++ interpretive freely available from htpp:// Ch zlib Package alllows zlib applications with compression and decompression function runs in Ch across platform without compilation. Ch zlib Package includes the source code for building the binding to zlib.

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Posted in July 28th, 2004

Managed C++ wrapper for Zlib

In this article I present a namespace of managed types that provide a wrapper to some of the standard functionalities exported by ZLib. ZLib is a well known free, general-purpose lossless data-compression library for use on any operating system.


Posted in July 10th, 2004

ZLib dotNet

Microsoft .NET Stream-derived objects that wrap ZLib inflate and deflate functions (C++ Mixed Mode implementation)

Version 1.0.1 is shipping as of June, 2004.

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Posted in June 27th, 2004

Code to extract plain text from a PDF file

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.


Posted in May 31st, 2004

JZlib — zlib in pure Java

This project is an attempt to hoist zlib out of the C world and into pure Java land. This allows Java developers to take advantage of a few zlib features that aren’t available in the standard JDK packages. LGPL license.

Version 1.0.5 of Jzlib was shipping as of May, 2004.


Posted in May 22nd, 2004

FlacPack - Free lossless instrument file compression

This project aims to define a standard for the lossless compression of MIDI patch files. From the title, you might guess that the lossless audio compression is performed using FLAC - other binary data is compressed w/zlib.


Posted in December 14th, 2003


ZLib.Ada is a thick binding to the popular compression/decompression library ZLib. It is providing Ada style access to the ZLib C library.


Posted in December 6th, 2003


The zlib home page. zlib is a free software package that implements the deflate compression algorithm popularized in PKWare’s PKZIP product. zlib is designed to be patent free, and is free or restrictions.

Version 1.2.1 is shipping as of December, 2003.


Posted in December 1st, 2003

zipstream, bzip2stream: iostream wrappers for the zlib and bzip2 libraries

This article describes STL-compliant iostream implementations that compress and decompress using the deflate and bzip2 algorithms. It makes it really easy to use compressed streams in your C++ app.

Updated July, 2003, to fix a gzip header problem.

Updated August, 2003 to fix a couple of minor problems.


Posted in September 28th, 2003

This site is dedicated to discussion and explanation of HTTP compression with the Apache web server. Looks to me like the first place to go for information.


Posted in June 29th, 2003

Xceed Streaming Compression for .NET

Xceed Streaming Compression for .NET is an efficient and lightweight data compression class library for Microsoft .NET and ASP.NET. It can process any size byte array with ease and provides a true .NET pass-through stream object for automatically compressing or decompressing any .NET stream’s data on the fly. It supports the GZip, Zlib, Deflate and Deflate64 compression formats.

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Posted in June 22nd, 2003

Xceed Streaming Compression Library

The Xceed Streaming Compression Library is a high-performance “raw” compression library. It offers the ability to compress and decompress streaming data, buffers, strings or single files and supports multiple compressed data formats. Unlike the Xceed Zip Compression Library, this ultralight library doesn’t offer Zip file handling capabilities.

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Posted in June 21st, 2003

Xceed Zip for .NET Compact Framework

Xceed Zip for .NET Compact Framework is a data compression and all-purpose file manipulation class library for creating mobile apps. It provides flexible zip, gzip and streaming data compression capabilities for compact applications created with Visual Studio .NET 2003. The library includes an innovative and extensible filesystem object model that makes zip files as easy to work with as regular files or folders.

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Posted in June 21st, 2003

Bob Crispen’s Port of Zlib to lcc

Win-GZ is built for the Win32 environment using Jacob Navia’s lcc-Win32. The zip file referenced here contains the modifications needed to get zlib to build under this environment.


Posted in March 22nd, 2003

Zlib compression / decompression wrapper as ISequentialStream

This is a first shot at wrapping zlib compression library behind a COM IStream interface. The library provides a pure ATL C++ implementation and a simple demo COM based implementation. Both take an IStream as an initializer and compress/decompress on the fly on the Read and Write methods.


Posted in February 17th, 2003


This project provides an implementation of the classes. The code is pure java (no native code is used), and aims to be compatible with existing implementations.

Version 0.06 of jazzlib shipped in January of 2003. This product is still under development, but I don’t have a clear roadmap, no idea when to expect a 1.0 release.


Posted in February 15th, 2003

The Zip, GZip, BZip2 and Tar Implementation For .NET

#ziplib (SharpZipLib, formerly NZipLib) is a Zip, GZip, Tar and BZip2 library written entirely in C# for the .NET platform. It is implemented as an assembly (installable in the GAC), and thus can easily be incorporated into other projects (in any .NET language). The creator of #ziplib put it this way: “I’ve ported the zip library over to C# because I needed gzip/zip compression and I didn’t want to use libzip.dll or something like this. I want all in pure C#.”

Visitor Samuel L. had this to say Extremely useful and well written, well done, great that is open source.

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Posted in September 9th, 2002

zlib information

Published in Links, zlib

Some information and assorted links regarding zlib.


Posted in April 7th, 2002

Zlib flaw leaves Linux computers vulnerable

CNET reports the existence of a bug in zlib that leaves room for security exploits. The bug is one that occurs when a program attempts to free allocated memory twice, which leaves the internals of the library in an unpredictable state.


Posted in March 19th, 2002

ZLib for Kylix

A short description of how one goes about using zlib in Kylix.

Reader Michael wasn’t too happy with what he found here: The article is unclear and does not explain the reason or logic behind anything the creator has done. I see no point in linking back to the zlib unit under Kylix/Linux if that is the file you are trying to cross-compatify.


Posted in February 25th, 2002

Wikipedia entry: deflate

This Wikipedia entry describes the deflate compression algorithm. Very terse, could use an update from a DCL reader!


Posted in January 27th, 2002

zlib for WinCE

Source code and demo projects from Ciprian Miclaus. Ciprian said he created this because the only other available port for CE did not include source.
DCL reader Mike P. said Very good … especially that I found on the same site a port of libbzip2 for WinCE. Excellent … exactly what my project needed.

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Posted in January 14th, 2002

Zip Home Page

Zip is a free .NET Zip File library which works with C# or other languages that use the CLR.


Posted in January 4th, 2002

Huffman Compression Engine

This program is currently capable of reading and extracting files made with LHA and other utilities that generate .lzh files, from -lh4- to -lh7-. The foundation of the algorithm for this program like ARJ is based on Haruhiko Okumura’s work on ar002, which was the foundation of LHA. Unlike Haruhiko’s work however, the dictionary size is dynamic and currently allows for dictionary sizes of up to 64KB. On larger files, compression of files is usually 0.5% to 5% tighter than PKzip, and work in progress will likely yield even better results. Files created with this utility natively create -lh7- signed archives, which on larger files results in slightly better compression than that of lha32 by Haruyasu Yoshizaki.


Posted in January 1st, 2002


A Japanese language site that is somehow related to zlib.

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Posted in December 24th, 2001


A port of Zlib to the Palm O/S platform. Creates a free shared library, and reportedly is used in one app to decompress PNG images.


Posted in November 28th, 2001

An Explanation of the Deflate Algorithm

This includes a brief discussion of Huffman coding, then of LZ77 compression, and finally some of the coding oddities that are found in deflate.

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Posted in August 23rd, 2001

Deflate technical spec in PS format

The deflate technical specification in US size PostScript, by L. Peter Deutsch. This document is the basis for RFC 1951.

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Posted in August 23rd, 2001

DEFLATE Compressed Data Format Specification version 1.3

The deflate technical specification in HTML, by L. Peter Deutsch. This document is the basis for RFC 1951. There are many links to this document stored in various places, but this database will only have links to the versions at and the IETF pages.


Posted in August 23rd, 2001

ZLIB Compressed Data Format Specification version 3.3

The zlib technical specification in HTML, by L. Peter Deutsch and Jean-Loup Gailly.


Posted in August 23rd, 2001