
USING THE IJG JPEG LIBRARY
Copyright (C) 1994-1998, Thomas G. Lane.
This file is part of the Independent JPEG Group's software.
For conditions of distribution and use, see the accompanying README file.
This file describes how to use the IJG JPEG library within an application
program. Read it if you want to write a program that uses the library.
The file example.c provides heavily commented skeleton code for calling
the
JPEG library. Also see jpeglib.h (the include file to be used by
application
programs) for full details about data structures and function parameter
lists.
The library source code, of course, is the ultimate reference.
Note that there have been *major* changes from the application interface
presented by IJG version 4 and earlier versions. The old design had
several
inherent limitations, and it had accumulated a lot of cruft as we added
features while trying to minimize application-interface changes. We have
sacrificed backward compatibility in the version 5 rewrite, but we think
the
improvements justify this.
TABLE OF CONTENTS
-----------------
Overview:
Functions provided by the library
Outline of typical usage
Basic library usage:
Data formats
Compression details
Decompression details
Mechanics of usage: include files, linking, etc
Advanced features:
Compression parameter selection
Decompression parameter selection
Special color spaces
Error handling
Compressed data handling (source and destination managers)
I/O suspension
Progressive JPEG support
Buffered-image mode
Abbreviated datastreams and multiple images
Special markers
Raw (downsampled) image data
Really raw data: DCT coefficients
Progress monitoring
Memory management