Last Updated: 10 Feb 1997
The premier JPEG toolkit is the Independent JPEG Group's JPEG Toolkit available via FTP . This toolkit contains free, widely-portable C code for JPEG compression, complete with documentation and test files. The latest version, 6a, is available tarred and gnu zipped from via FTP. A PKZIPed MS-DOS archive of the same package is also available via FTP.
The IJG code includes a reusable JPEG compression/decompression library, plus sample applications cjpeg and djpeg, which perform conversion between JPEG JFIF format and image files in PPM/PGM (PBMPLUS), GIF, BMP, Utah RLE, and Targa formats. A third application, jpegtran, provides lossless transcoding between different JPEG formats (such as baseline to progressive). Two additional applications, wrjpgcom and rdjpgcom, insert and extract textual comments in JFIF files. Other JPEG software packages and hardware codecs also exist. Have a look at the JPEG FAQ and part 3 of the comp.compression FAQ for more details.
Markus Kuhn's freely available JBIG-KIT is a portable ANSI C library which implements a highly effective and lossless bi-level image compression algorithm based on JBIG, a context sensitive arithmetic coding algorithm described in the ITU-T Recommendation T.82. JBIG is especially suitable for compressing two-color scanned documents and fax pages, although grayscale and color data compression by bitplane is possible. Also have a look at Markus' Home Page.
Available MPEG players include the UC Berkeley MPEG Decoder for Unix, DOS, and Windows, Xanim for many flavors of Unix, MPEG Player also for X and Motif, and Sparkle 2 for the Macintosh.
MPEG information is available from the Scientific Visualization Group's MPEG FAQ, Enterprise Integration Technologies, and the Optibase Library. Also have a look at the C-Cube's MPEG Overview, and part 3 of the comp.compression FAQ for more details. And a nice How to Make MPEG Movies page is here.
The first places to look for QuickTime information and software is Apple Computer's QuickTime and QuickTime VR, and QuickTime Developer's Support pages. (QuickTime developer's support is alternately available here).
QuickTime movie players and editors are available for all popular operating systems, including:
Many more QuickTime-savvy applications can be fund listed in the QuickTime FAQ and the Cross-platform QuickTime page.
The primary toolkit for working with CCITT Group 3 & 4 compressed images is Sam Leffler's TIFF Toolkit. Alan Finlay's software for reading and writing CCITT Group 3 and 4 images is available via FTP More information on facsimile and the CCITT compression methods in the Facsimile Subsection of the WWW Virtual Library, the comp.compression FAQ, and the comp.dcom.fax FAQ.
H.261 is a video codec (coder/decoder) standard used for compressing real-time video data (also known as the P*64 compression method). G.711 and G.726 are audio encoding standards (PCM and ADPCM respectively) used to compress the real-time audio that often accompanies a video signal. All of these recommendation form part of the H.320 video teleconferencing recommendation.
The H Series of recommendations form a group of standards for video conferencing. The G Series of recommendations define. These recommendations are published by the ITU and are usually only available at cost. You can find all of these standards documents listed on the IMTC home page. You also should really have a look at the Video Conferencing FAQ.
Here are a few of the Web's many pages devoted to fractal image compression.
File archiving programs are often used to compress graphics files that are normally uncompressed and to store multiple image files in a single file. Here are a few of the many available file compression and archiving programs (and all of which are available here).
And for the whereabouts of any other file compressors and archivers, have a look at the Archive comparison Test, the Archive Comparison Test by Jeff Gilchrist, and the PHOAKS Archive Comparison Test
If you are interested in serious speed for your software that requires data compression and decompression, then it is time you looked at the state-of-the-art hardware.
The Stuart Inglis Compression Ratios page. Also check out Stuart's Compression Pointers page.
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