User manual - V-N500取扱説明書(2014年05月07日)

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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.