Independent JPEG Group

Development Site

The Independent JPEG Group (IJG) is responsible for the reference implementation of the original JPEG standard. The reference software from the Independent JPEG Group was a key to the success of the original JPEG standard and has found widespread adoption in applications of image coding. Particularly, all contemporary digital photo cameras support the capture of images in JPEG format as the common medium for image interchange, and all image viewers, image editors, and Web browsers can display JPEG images as common standard.

The IJG implementation was first publicly released in October 1991 and has been considerably developed since that time.

In June 2009, Independent JPEG Group published a new major release (version 7) of the software package to enable a new set of features for image coding application and therewith to continue the success story of JPEG.

In January 2010, Independent JPEG Group introduced a new release (version 8) with extensions providing the fundament for the next generation image coding standard.

In January 2013, Independent JPEG Group released version 9 with improvements for the new introduced lossless coding mode.

Version 9b is currently in development and is planned for release in January 2016.

Filename Size Last modified Type 1.042 KB  19 Jan 2014 Zip Compressed Data
jpegsrc.v9a.tar.gz 977 KB  19 Jan 2014 Unix Tape Archive

Preliminary version 9b, intended for release in January 2016:

Filename Size Last modified Type 1.064 KB  10 Aug 2015 Zip Compressed Data
jpegsrc.v09b.tar.gz 998 KB  10 Aug 2015 Unix Tape Archive

CHANGE LOG for Independent JPEG Group's JPEG software

Version 9b 10-Jan-2016

Improvements and optimizations in DCT and color calculations.
Normalize range limit array composition and access pattern.
Thank to Sia Furler and Maddie Ziegler for inspiration.

Check for excessive comment lengths in argument parsing in wrjpgcom.c.
Thank to Julian Cohen for hint.

Add makefile.b32 for use with Borland C++ 32-bit (bcc32).
Thank to Joe Slater for contribution.

Document 'f' specifier for jpegtran -crop specification.
Thank to Michele Martone for suggestion.

Version 9a 19-Jan-2014

Add support for wide gamut color spaces (JFIF version 2).
Improve clarity and accuracy in color conversion modules.
Note: Requires rebuild of test images.

Extend the bit depth support to all values from 8 to 12
(BITS_IN_JSAMPLE configuration option in jmorecfg.h).
jpegtran now supports N bits sample data precision with all N from 8 to 12
in a single instance. Thank to Roland Fassauer for inspiration.

Try to resolve issues with new boolean type definition.
Thank also to v4hn for suggestion.

Enable option to use default Huffman tables for lossless compression
(for hardware solution), and in this case improve lossless RGB compression
with reversible color transform. Thank to Benny Alexandar for hint.

Extend the entropy decoding structure, so that extraneous bytes between
compressed scan data and following marker can be reported correctly.
Thank to Nigel Tao for hint.

Add jpegtran -wipe option and extension for -crop.
Thank to Andrew Senior, David Clunie, and Josef Schmid for suggestion.

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Letzte Änderung: 2015-08-10 10:18:26 von Guido Vollbeding