Transcript What is Scientific Visualization

Scientific Visualization
By: Jesus Caban
and
Chi Chau
What is Scientific Visualization?
Visualization for scientific computing,
shortened to scientific visualization, was
coined in 1987 and refers to the science or
methodology of quickly and effectively
displaying scientific data.
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1987 NSF report: “Visualization in Scientific Computing”
Formal name given to the field in computer
science that includes user interface, data
representation and processing algorithms,
visual representations and other sensory
presentation such as sound or touch.
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www.caida.org
Motivation
In computational science we can
use distributed computers and
powerful clusters to simulate
complex and realistic problems.
It is difficult for the human brain to
make sense out of the large volume
of numbers
Can we enhance and improve
scientific productivity by utilizing
human visual perception and
computer graphics techniques?
What can we do with the resulting
numbers, formulas and data?
Scientific Visualization vs. Data Visualization
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Scientific Visualization:
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graphical representations from the results of
mathematical models, computations and simulations
Involves research in computer graphics, image
processing, high performance computing, and other
areas
It's not just a pretty picture or animation
Data Visualization:
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More general term
Implies treatment of data source beyond science and
engineering, such as financial, business data, etc.
Visualization is not only looking into a pretty
picture…
– understanding of the data
– been able to analyze and interpret data
Spot Noise
http://www.llnl.gov/graphics/spot.html
Applications
Used in:
– Engineering
– Computational Fluid
Dynamics
– Simulation
– Medical Imaging
– Geospatial
– Ground Water Modeling
– Oil and Gas Exploration
and Production
– and more…
Concepts associated with Visualization
Personal visualization:
analyze results, graphics in
your PC.
High-resolution displays:
visualization of large-data sets.
Immersive visualization: an
environment where the user is
immersed in the computer
generated 3D graphics.
Collaborative visualization:
two or more users visualize the
same data using different
displays.
Concepts associated with Visualization
(cont.)
From NASA
Stereo Displays:
Active Stereo:
Polarized
Anaglyphic
Holographic/Auto-stereoscopic displays
multiple viewpoints at the same time
Head-mounted displays
two small monitors integrated into a
headset which stimulate a large part of the
user's field of view
www.actuality-systems.com
“Trivial” Examples
2D plot
– Matlab
t = 0:0.01:5;
y = sin(4*t);
plot(t,y);
3D plot
– Matlab
[x,y] = meshgrid(-2:.1:2, -2:.1:2);
z = x .* exp(-x.^2 - y.^2);
mesh(z)
More advance example
Animation in Matlab
From http://www.oc.nps.navy.mi
Other techniques
3D points
X
Y
Z
101.32
98.2
43.2
102.01
98.2
46.4
….
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Result:
– A 3D object that we ca
can visualize
Hardware
Hardware for large data
sets
– Supercomputer
– Clusters with commodity
hardware
Stereo Visualization
– ImmersaDesk
Do we need
supercomputers?
– What about Nvidia/ATI
video cards in a PC or
cluster?
Some Visualization Tools
Amira in Medical
Advanced 3D visualization and volume
modeling tool to process 3D data sets
It allows you to gain detailed insight into
your data. Graphics hardware support is
utilized to display even very large data sets
at interactive speed
It mainly use in visualize 3D images data
such as CT, MR, confocal, microscopy
The image depicts a surface model of the human head and the brain
created from an MRI data set. Amira provides a "realistic"
transparency mode for surface display (outer surface). Arbitrary fields
can be mapped onto the surface (inner surface).
General relativistic simulation of
gravitational energy. Visualization
by W. Benger, Simulation by AEI
Potsdam
OpenGL Performer in Games
OpenGL Performer is a powerful and
comprehensive programming interface for
developers creating real-time visual simulation
and other performance-oriented 3D graphics
applications. It simplifies development of
complex applications used for visual simulation,
manufacturing, simulation-based design, virtual
reality, scientific visualization, interactive
entertainment, broadcast video, architectural
walk-through, and computer-aided design.
Performer Town: Visual Simulation scene This rural town environment was one of
the first real-time databases ever seen on the RealityEngine. It was modeled by
Wes Hoffman of Paradigm Simulation using the MultiGen database modeling tool
and is explored using Perfly, the sample real-time application distributed with
OpenGL Performer. The trees, parking meters, and street lights in this scene are
flat textured polygons rotated to face the eyepoint each frame. The traffic signals are
animation sequences and cycle between green, yellow, and red states automatically
GeoWall in Geo
A good understanding of spatial relationships is
a fundamental requirement in the study of the
Earth Sciences. Traditional teaching methods
have strongly relied on the 2D representations
through maps and profiles that are occasionally
augmented by physical models. Although most
Earth Scientists have been trained to understand
the 3D structure from such representations, the
extrapolation requires spatial thinking skills that
are difficult to learn and often form a stumbling
block for students at the introductory level.
GeoWall Con’t
The GeoWall mission is to broaden the use
of scientific visualization tools for Earth
Science research and education by the
use of low cost virtual reality visualization
devices. The current GeoWall hardware is
based on Agave technology developed at
the Electronic Visualization Lab
Software & Hardware Needed
Software – image display for GeoWall
OpenGL base, stereo pair, vpokescope,
viewer, wallview
Software – geometry display
2Space assistant, coanim, iView 3D etc
Hardware – Projectors, Screens, Linear
Polarization Glases, Circular Polarization,
Projector Stackers, Graphics Boards and
Stereo Cameras
Vis5D - Weather
Vis5D is a system for interactive visualization of
large 5-D gridded data sets such as those
produced by numerical weather models. One
can make isosurfaces, contour line slices,
colored slices, volume renderings, etc of data in
a 3-D grid, then rotate and animate the images
in real time. There's also a feature for wind
trajectory tracing, a way to make text anotations
for publications, support for interactive data
analysis, etc.
FieldView – Fluid Dynamics
FieldView is the World's Leading Postprocessing and Visualization for
Computational Fluid Dynamics
It illustrates the
Velocity profile within
an Engine Block
This is one of a series
of images used by
Lockheed Martin at
the 1997 Paris Air
Show. An animation
was created with
FieldView, and
projected onto a scale
model of an F22
aircraft.
Pressure contours
and velocity vectors
on an F18. - Data
courtesy Nasa
Langley Research
Center
References
www.ssec.wisc.edu/~billh/vis5d.html
www.amiravis.com
www.sgi.com
www.ilight.com
www.geowall.org