OBVIUS (Object-Based Vision and Image Understanding System) is an
image-processing system based on Common Lisp and CLOS (Common Lisp
Object System).  The system provides a flexible interactive user
interface for working with images, image-sequences, and other
pictorially displayable objects.  By using Lisp as its primary
language, the system is able to take advantage of the interpretive
lisp environment (the ``listener''), object-oriented programming, and
the extensibility provided by incremental compilation.

The basic functionality of OBVIUS is to present certain lisp objects
to the user pictorially.  These objects are refered to as "viewables".
Some examples of viewables are monochrome images, color images, binary
images, complex images, image sequences, image pyramids, filters and
discrete functions.  A "picture" is the displayable representation of
a viewable.  Note that a given viewable may be compatible with several
different picture types.  For example, a floating point image may be
displayed as an eight bit grayscale picture, as a one bit dithered
picture, as a 3D surface plot or contour plot.  OBVIUS also provides
postscript hardcopy output of pictures.

In the typical mode of interaction, the user types an expression to
the lisp listener and it returns a viewable, which is automatically
displayed as a picture in a window.  Each window contains a circular
stack of pictures.  Standard stack manipulation operations are
provided via mouse clicks (e.g., cycle, pop, and push).  Commonly used
operations such as histogram and zoom are also provided via mouse
clicks.

OBVIUS provides a library of image processing routines (e.g., point
operations, image statistics, convolutions, fourier transforms).  All
of the operations are defined on all of the viewable types.  The
low-level floating point operations are implemented in C for speed.
OBVIUS also provides a library of functions for synthesizing images.
In addition, it is straightforward to add new operations and new
viewable and picture types.

OBVIUS currently runs on Sun workstations in Lucid v4.0 Common Lisp.
It also requires the LispView interface to OpenWindows/X, which is
available free of charge on the X11 distribution tape.  It is also
included in the ftp directory on white.stanford.edu.

OBVIUS is available via anonymous ftp from white.stanford.edu,
IP number 36.121.0.16.  Documentation (latex), and a User's Guide with
installation instructions are included in the tarfile.  Since it is
currently an in-house product it comes without warrantee or support.
For more information contact:

David Heeger 
heeger@white.stanford.edu

Eero Simoncelli
eero@whitechapel.media.mit.edu

Let us know if you get a copy of OBVIUS at your site so that we can
keep a list of everybody (to send out bug fixes, inform you of new
releases, etc.)