Independent JPEG Group
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 was released in January 2016 and is the only true source reference JPEG codec.
|jpegsr9b.zip||1.065 KB||17 Jan 2016||Zip Compressed Data|
|jpegsrc.v9b.tar.gz||999 KB||17 Jan 2016||Unix Tape Archive|
CHANGE LOG for Independent JPEG Group's JPEG software
Version 9b 17-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.
Use merged upsample with scaled DCT sizes larger than 8.
Thank to Taylor Hatala 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.
Use defined value from header instead of hardwired number in rdswitch.c.
Thank to Robert Sprowson for hint.
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.
Letzte Änderung: 2016-04-22 18:02:11 von Guido Vollbeding