README for OpenImageIO
======================


Introduction
------------

OpenImageIO consists of:

  * Simple but powerful ImageInput and ImageOutput APIs that provide
    an abstraction for reading and writing image files of nearly any
    format, without the calling application needing to know any of the
    details of these file formats, and indeed without the calling 
    application needing to be aware of which formats are available.

  * A library that manages subclasses of ImageInput and ImageOutput that
    implement I/O from specific file formats, with each file format's
    implementation stored as a plug-in.  Therefore, an application using
    OpenImageIO's APIs can read and write any image file for which a
    plugin can be found at runtime.

  * Plugins implementing I/O for several popular image file formats,
    including TIFF, JPEG/JFIF, OpenEXR, PNG, HDR/RGBE, ICO, BMP, Targa,
    JPEG-2000, RMan Zfile, FITS, DDS, Softimage PIC.  More are being
    developed all the time.

  * An image viewer, iv, that is based on ImageIO plugins and therefore
    can read images of any format for which an appropriate plugin may be
    found.

  * Several image tools based on these classes, including iinfo (print
    detailed info about images), iconvert (convert among formats, data
    types, or modify metadata), idiff (compare images), igrep (search
    images for matching metadata). Because these tools are based on
    ImageInput/ImageOutput, they work with any image formats for which
    ImageIO plugins are available.

  * An ImageCache class that transparently manages a cache so that it
    can access truly vast amounts of image data (thousands of image
    files totaling hundreds of GB) very efficiently using only a tiny
    amount (tens of megabytes at most) of runtime memory. Additionally,
    a TextureSystem class provides filtered MIP-map texture lookups,
    atop the nice caching behavior of ImageCache.



Licensing
---------

OpenImageIO is (c) Copyright 2008 by Larry Gritz and the other
contributors.  All Rights Reserved.

OpenImageIO is distributed using the modified BSD license.  Please read
the "LICENSE" file for the legal wording.  The plain English bottom line
is that OpenImageIO is free, as well as freely modifiable and
redistributable (in both source and binary form).  You may use part or
all of it in your own applications, whether proprietary or open, free or
commercial or not.  Using it in a commercial or proprietary application
DOES NOT obligate you to pay us, or to use any particular licensing
terms in your own application.


Web Resources
-------------

Main web page:      http://www.openimageio.org
Bug/issue tracker:  http://trac.openimageio.org
Mail lists:         http://lists.openimageio.org


Contact
-------

info@openimageio.org



Building and Installation
-------------------------

Please read the "INSTALL" file for detailed instructions on how to
build and install OpenImageIO.

Remember that you need to set the environment variable
IMAGEIO_LIBRARY_PATH to point to the 'lib' directory where OpenImageIO
is installed, or else it will not be able to find the plugins.


Documentation
-------------

The primary user and programmer documentation can be found in
src/doc/openimageio.pdf (in a source distribution) or in the
doc/openimageio.pdf file of an installed binary distribution.