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The Independent JPEG Group's JPEG software
==========================================

README for release 9a of 19-Jan-2014
====================================

This distribution contains the ninth public release of the Independent JPEG
Group's free JPEG software.  You are welcome to redistribute this software and
to use it for any purpose, subject to the conditions under LEGAL ISSUES, below.

This software is the work of Tom Lane, Guido Vollbeding, Philip Gladstone,
Bill Allombert, Jim Boucher, Lee Crocker, Bob Friesenhahn, Ben Jackson,
Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi, Ge' Weijers,
and other members of the Independent JPEG Group.

IJG is not affiliated with the ISO/IEC JTC1/SC29/WG1 standards committee
(previously known as JPEG, together with ITU-T SG16).


DOCUMENTATION ROADMAP
=====================

This file contains the following sections:

OVERVIEW            General description of JPEG and the IJG software.
LEGAL ISSUES        Copyright, lack of warranty, terms of distribution.
REFERENCES          Where to learn more about JPEG.
ARCHIVE LOCATIONS   Where to find newer versions of this software.
ACKNOWLEDGMENTS     Special thanks.
FILE FORMAT WARS    Software *not* to get.
TO DO               Plans for future IJG releases.

Other documentation files in the distribution are:

User documentation:
  install.txt       How to configure and install the IJG software.
  usage.txt         Usage instructions for cjpeg, djpeg, jpegtran,
                    rdjpgcom, and wrjpgcom.
  *.1               Unix-style man pages for programs (same info as usage.txt).
  wizard.txt        Advanced usage instructions for JPEG wizards only.
  change.log        Version-to-version change highlights.
Programmer and internal documentation:
  libjpeg.txt       How to use the JPEG library in your own programs.
  example.c         Sample code for calling the JPEG library.
  structure.txt     Overview of the JPEG library's internal structure.
  filelist.txt      Road map of IJG files.
  coderules.txt     Coding style rules --- please read if you contribute code.

Please read at least the files install.txt and usage.txt.  Some information
can also be found in the JPEG FAQ (Frequently Asked Questions) article.  See
ARCHIVE LOCATIONS below to find out where to obtain the FAQ article.

If you want to understand how the JPEG code works, we suggest reading one or
more of the REFERENCES, then looking at the documentation files (in roughly
the order listed) before diving into the code.


OVERVIEW
========

This package contains C software to implement JPEG image encoding, decoding,
and transcoding.  JPEG (pronounced "jay-peg") is a standardized compression
method for full-color and gray-scale images.

This software implements JPEG baseline, extended-sequential, and progressive
compression processes.  Provision is made for supporting all variants of these
processes, although some uncommon parameter settings aren't implemented yet.
We have made no provision for supporting the hierarchical or lossless
processes defined in the standard.

We provide a set of library routines for reading and writing JPEG image files,
plus two sample applications "cjpeg" and "djpeg", which use the library to
perform conversion between JPEG and some other popular image file formats.
The library is intended to be reused in other applications.

In order to support file conversion and viewing software, we have included
considerable functionality beyond the bare JPEG coding/decoding capability;
for example, the color quantization modules are not strictly part of JPEG
decoding, but they are essential for output to colormapped file formats or
colormapped displays.  These extra functions can be compiled out of the
library if not required for a particular application.

We have also included "jpegtran", a utility for lossless transcoding between
different JPEG processes, and "rdjpgcom" and "wrjpgcom", two simple
applications for inserting and extracting textual comments in JFIF files.

The emphasis in designing this software has been on achieving portability and
flexibility, while also making it fast enough to be useful.  In particular,
the software is not intended to be read as a tutorial on JPEG.  (See the
REFERENCES section for introductory material.)  Rather, it is intended to
be reliable, portable, industrial-strength code.  We do not claim to have
achieved that goal in every aspect of the software, but we strive for it.

We welcome the use of this software as a component of commercial products.
No royalty is required, but we do ask for an acknowledgement in product
documentation, as described under LEGAL ISSUES.


LEGAL ISSUES
============

In plain English:

1. We don't promise that this software works.  (But if you find any bugs,
   please let us know!)
2. You can use this software for whatever you want.  You don't have to pay us.
3. You may not pretend that you wrote this software.  If you use it in a