Open Source Windows File Compression Software

LZ4 is lossless compression algorithm, providing compression speed > 500 MB/s per core (>0.15 Bytes/cycle). It features an extremely fast decoder, with speed in multiple GB/s per core (~1 Byte/cycle). A high compression derivative, called LZ4_HC, is available, trading customizable CPU time for compression ratio. LZ4 library is provided as open-source software using a BSD license. This benchmark simulates simple "static content transfer" scenario such as OS Kernel compression or video game's static assets (text/images/tables/scripts/etc) which loading from Flash Memory / HDD / SSD. In this case, compression time is completely ignored. Because only content developers compress the data at once and usually they don't care about its computational cost. But they always care end user's experience a.k.a. "loading time" and bandwidth. Please pay attention to "LZ4HC -9" which is quite faster than other methods.

Zstandard is a fast compression algorithm, providing high compression ratios. It also offers a special mode for small data, called dictionary compression. The reference library offers a very wide range of speed / compression trade-off, and is backed by an extremely fast decoder (see benchmarks below). Zstandard library is provided as open source software using a BSD license. Its format is stable and published as IETF RFC 8478. The negative compression levels, specified with --fast=#, offer faster compression and decompression speed in exchange for some loss in compression ratio compared to level 1, as seen in the table above. Zstd can trade compression speed for stronger compression ratios. It is configurable by small increment. Decompression speed is preserved and remain roughly the same at all settings, a property shared by most LZ compression algorithms, such as zlib or lzma.

pngcrush and other tools for manipulating PNG (Portable Network Graphics) and MNG (Multiple-image Network Graphics) files.

Abbrevia is a compression toolkit for Delphi, C++Builder, Kylix, and Free Pascal. It supports compressing and decompressing PKZIP, Microsoft CAB, tar, gzip, and bzip2 archives, and can create self-extracting executables. On Windows it also provides Delphi wrappers for the LZMA, Bzip2, and WavPack SDKs, and PPMd decompression. Abbrevia also has several visual controls that simplify displaying and manipulating archives, including treeview and listview components.

It supports files and folders multi-compression (UPX, ZIP, 7Z) and archives extraction (several formats). It includes an intelligent UPX compression mode, self-extracting archive creation, encryption/decryption, external compressors and much more.

Native (JNI) cross-platform library to extract (password protected, multi-part) 7z Zip Rar Tar Split Lzma Iso HFS GZip Cpio BZip2 Z Arj Chm Lhz Cab Nsis Deb Rpm Wim Udf archives and create 7z, Zip, Tar, GZip & BZip2 from Java.

a Java utility for comparing the contents of any two zip files. It can also be used to compare EAR files, WAR files, or JAR files.

minidjvu is a DjVu encoder for black-and-white images.

CADI is an implementation of the JPIP standard (JPEG2000 Interactive Protocol - Part 9). CADI includes a JPIP server, a JPIP proxy, and a JPIP Client. CADI is designed and programmed with the aim to provide a flexible framework to test and develop ne

UPX Tool is a GUI for the popular UPX EXE Compressor. Windows Programs and Dlls, and DOS Programs can be compressed.

The ZLib.Ada is a thick binding to the popular compression/decompression library ZLib http://www.gzip.org/zlib/. ZLib.Ada provide Ada style access to the ZLib C library.

This project has moved to GitHub https://github.com/Zipios/Zipios Zipios is a C++ library for reading and writing Zip archive files. Access to the data of individual entries is provided through standard C++ iostreams. A simple read-only virtual file system that mounts regular directories and zip files is also provided.

TER implements the CCSDS Recommendation for Image Data Compression (CCSDS 122.0-B-1). TER also adds new features to the Recommendation. TER is designed and programmed with the aim to provide a good basis to test and develop the CCSDS Recommendation.

OpenDark is a free simplification of 'dark'. It's the first open BWT-DC compressor, which has a simple code, high speed and compression ratio. And it's waiting for your ideas! :)

liblzg is a minimal implementation of an LZ77 class compression library. The main characteristic of the library is that the decoding routine is very simple, fast and requires no memory.

.NET wrapper for 7Zip, based on 7-Zip-JBinding, produced with IKVM. Extracts (password protected, multi-part) 7z Zip Rar Tar Split Lzma Iso HFS GZip Cpio BZip2 Z Arj Chm Lhz Cab Nsis Deb Rpm Udf archives. Archive creation/more formats coming soon.

AGfUPX is a nice GUI for UPX with many advantages. Selecting a file using drag & drop, shell integration (adding "Open with AGfUPX" option to the context menu of exe/dll files) and redirecting UPX output to a windows dialog box are only few of them.

Track all your files, locally, on CD-ROMs, and on removables.

CodersBackup is an advanced automatic folder zip backup system. Helps coders (programmers) backup their work based on filters, schedules. Destinations can be local hard disk and/or network and/or FTP. Special actions can be taken during backup.

CAKE is built for Delphi, it's a common interface for 5-6 components related to compression, that means, you can use single code to command all those components, providing open, extract, add, test, convert, find and script loading support.

Lepton image compression, saving 22% losslessly from images at 15MB/s. Lepton achieves a 22% savings reduction for existing JPEG images, by predicting coefficients in JPEG blocks and feeding those predictions as context into an arithmetic coder. Lepton preserves the original file bit-for-bit perfectly. It compresses JPEG files at a rate of 5 megabytes per second and decodes them back to the original bits at 15 megabytes per second, securely, deterministically, and in under 24 megabytes of memory. We have used Lepton to encode 16 billion images saved to Dropbox, and are rapidly recoding our older images. Lepton has already saved Dropbox multiple petabytes of space. At Dropbox, the security and durability of your data are our highest priorities. As an added security layer, Lepton runs within seccomp to disable all system calls except read and write of already-open file descriptors. Lepton has gone through a rigorous automated testing process.

Major looseless compression algorithms library and documentation. First project: Arithmetic, Huffman, LZ77, LZ78, LZW, RLE. Second project reimplements Deflate. Documentation explains major Entropy Compression Methods.

Originally developed as a GUI replacement for the JAR utility included with the Java SDK, this program is expanding to become a cross platform archive utility with the ability to create fully cross platform installation programs.

LZO is a compression library which is widely used around the world. The main problem with LZO is that it is absolutely not human readable. People have done crazy stuff to get LZO to run in their language. Usually it implies inline assembly or trying to execute data which actually contains machine code. This is sick. Whoever is responsible for this sorry situation ought to be ashamed. So I'm going to deobfuscate LZO and provide a ISC implementation of this algorithm in Python and C. In addition, I will provide a textual description of the algorithm so that it can be easily ported to any programming language. I expect a severe performance degradation, but I leave optimizing for speed to other people.

GD RCS is a revision contol system which supports repository on removable media. It combines the abilities of PRCS, archiving tools like Zip and backup utilities.