libjpeg-turbo is a high-speed version of libjpeg for x86 and x86-64 processors. It uses SIMD instructions (MMX, SSE, SSE2) to accelerate baseline JPEG compression and decompression. libjpeg-turbo is generally 2-4 times as fast as the unmodified version of libjpeg. It also includes a wrapper library for the TurboJPEG API used by VirtualGL and TurboVNC. It was originally based on libjpeg/SIMD but has improved support for Mac OS X, 64-bit platforms, 32-bit and big endian pixel formats (RGBA/BGRA/ABGR/ARGB), accelerated Huffman encoding/decoding, and various other fixes.
Various archive formats can be created, extracted, tested, listed, searched, compared, and repacked by patool. The advantage of patool is its simplicity in handling archive files without having to remember myriad programs and options. The archive format is determined by the file(1) program and as a fallback by the archive file extension. patool supports 7z (.7z), ACE (.ace), ADF (.adf), ALZIP (.alz), APE (.ape), AR (.a), ARC (.arc), ARJ (.arj), bzip2 (.bz2), CAB (.cab), COMPRESS (.Z), CPIO (.cpio), deb (.deb), DMS (.dms), FLAC (.flac), gzip (.gz), ISO (.iso), LRZIP (.lrz), LZH (.lha, .lzh), LZIP (.lz), LZMA (.lzma), LZOP (.lzo), RPM (.rpm), RAR (.rar), RZIP (.rz), SHN (.shn), tar (.tar), XZ (.xz), zip (.zip, .jar), and ZOO (.zoo) formats. It relies on helper applications to handle those archive formats (for example bzip2 for BZIP2 archives). The archive formats tar, zip, bzip2, and gzip are supported natively and do not require helper applications to be installed.
Opendedup is a project that develops a deduplication based filesystem for Windows and Linux called SDFS. SDFS is designed to support the unique needs of virtual environments and supports enhanced functionality for VMWare, Xen, and KVM. It can deduplicate a petabyte or more of data. It supports over 3TB per gigabyte of memory at a 128k chunk size. It can perform deduplication/reduplication at a line speed of 250 MB/s or more. VMware support: it works with vms, and can deduplicate at 4k block sizes. This is required to deduplicate Virtual Machines effectively Deduplicated data can be stored locally, on the network across multiple nodes, or in the cloud. The filesystem can deduplicate inline or periodically based on needs. This can be changed on the fly. There is support for file or folder level snapshots.
BZip2/OSS-QM is the OSS-QM project's branch of bzip2, which contains a lot of fixes not yet in the original upstream. The primary goal is to provide QM'ed/fixed versions of upstream releases, so they can be built and used without additional patches, especially in sysrooted crosscompiling environments.
Multicrush is a wrapper around pngcrush that distributes the work of brute-force compressing a single image over several pngcrush processes. This gets you a slightly less than a linear speedup, caused by different compression methods having slightly different durations. For example, the author has measured a speedup of 1.92 on a 2-core Intel T5300, and 3.86 on a 4-core Intel Q6600. The only requirements are a copy of pngcrush and at least Python 2.4. If you have version 2.6 or higher, multicrush can automatically detect how many CPUs to use.
The ROHC library provides an easy and robust way for applications to reduce their bandwidth usage on network links with limited capacity or expensive costs. Headers of network packets are compressed with the ROHC protocol and algorithms. The ROHC protocol is very efficient for compressing VoIP streams which use RTP as a transport protocol. ROHC is also suitable for compressing IP-only (IPv4 or IPv6) flows, UDP flows, and many others.
S3QL is a file system that stores all its data online. It supports Amazon S3, Google Storage, and OpenStack and effectively provides you with a hard disk of dynamic, infinite capacity that can be accessed from any computer with Internet access. S3QL provides a standard, full featured Unix file system that is conceptually indistinguishable from any local file system. Additional features include compression, encryption, data de-duplication, immutable trees, and snapshotting, which make it especially suitable for online backup and archiving. The design favors simplicity and elegance over performance and feature-creep. Care has been taken to make the source code as readable and serviceable as possible. Solid error detection, error handling, and extensive automated test cases are provided.