TAPE DECK

AIWA

00111

CARVER

00111

GRUNDIG

00111

HARMAN/KARDON

 

00111

MAGNAVOX

00111

MARANTZ

00111

MYRYAD

00111

OPTIMUS

00011

PHILIPS

00111

PIONEER

00011

POLK AUDIO

00111

RCA

00011

REVOX

00111

SANSUI

00111

SONY

00211

THORENS

00111

WARDS

00011

YAMAHA

00311, 00411

Information about software

This product uses the following software.

For information (copyright, etc) about each software, read the original sentences stated below.

■About The Independent JPEG Group's JPEG software

The Independent JPEG Group's JPEG software

README for release 6b of 27-Mar-1998

This distribution contains the sixth 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.

Serious users of this software (particularly those incorporating it into larger programs) should contact IJG at jpeg-info@uunet.uu.net to be added to our electronic mailing list. Mailing list members are notified of updates and have a chance to participate in technical discussions, etc.

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

IJG is not affiliated with the official ISO JPEG standards committee.

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.

RELATED SOFTWARE

Other stuff you should get.

FILE FORMAT WARS

Software *not* to get.

TO DO

Plans for future IJG releases.

Other documentation files in the distribution are:

User documentation:

 

install.doc

How to configure and install the IJG software.

usage.doc

Usage instructions for cjpeg, djpeg, jpegtran, rdjpgcom,

 

and wrjpgcom.

*.1

Unix-style man pages for programs (same info as

 

usage.doc).

wizard.doc

Advanced usage instructions for JPEG wizards only.

change.log

Version-to-version change highlights.

Programmer and internal documentation:

libjpeg.doc

How to use the JPEG library in your own programs.

example.c

Sample code for calling the JPEG library.

structure.doc

Overview of the JPEG library's internal structure.

filelist.doc

Road map of IJG files.

coderules.doc

Coding style rules --- please read if you contribute code.

Please read at least the files install.doc and usage.doc. Useful 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 compression and decompression. JPEG (pronounced "jay-peg") is a standardized compression method for full-color and gray-scale images. JPEG is intended for compressing "real-world" scenes; line drawings, cartoons and other non-realistic images are not its strong suit. JPEG is lossy, meaning that the output image is not exactly identical to the input image. Hence you must not use JPEG if you have to have identical output bits. However, on typical photographic images, very good compression levels can be obtained with no visible change, and remarkably high compression levels are possible if you can tolerate a low- quality image. For more details, see the references, or just experiment with various compression settings.

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. For legal reasons, we are not distributing code for the arithmetic-coding variants of JPEG; see LEGAL ISSUES. 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.

APPENDIX

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