What is Scientific Visualization

1
Scientific Visualization
By Jesus Caban and Chi Chau
2
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.
• 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.

www.caida.org
3
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?

4
Scientific Visualization vs. Data Visualization

• Scientific Visualization
• 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
• 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
5
Applications

• Used in
• Engineering
• Computational Fluid Dynamics
• Simulation
• Medical Imaging
• Geospatial
• Ground Water Modeling
• Oil and Gas Exploration and Production
• and more

6
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.

7
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
HMD
8
Trivial Examples

• 2D plot
• Matlab
• t 00.015
• y sin(4t)
• plot(t,y)
• 3D plot
• Matlab
• x,y meshgrid(-2.12, -2.12)
• z x . exp(-x.2 - y.2)
• mesh(z)

9
More advance example

• Animation in Matlab

From http//www.oc.nps.navy.mi
10
Other techniques

• 3D points

• Result
• A 3D object that we ca can visualize

11
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?

12
Some Visualization Tools
13
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

14
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).
15

• General relativistic simulation of gravitational
  energy. Visualization by W. Benger, Simulation by
  AEI Potsdam

16
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.

17

• 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

18
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.

19
GeoWall Cont

• 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

20
(No Transcript)
21
(No Transcript)
22
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

23
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.

24
(No Transcript)
25
(No Transcript)
26
FieldView Fluid Dynamics

• FieldView is the World's Leading Post-processing
  and Visualization for Computational Fluid Dynamics

27

• It illustrates the Velocity profile within an
  Engine Block

28

• 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.

29

• Pressure contours and velocity vectors on an F18.
  - Data courtesy Nasa Langley Research Center

30
References

• www.ssec.wisc.edu/billh/vis5d.html
• www.amiravis.com
• www.sgi.com
• www.ilight.com
• www.geowall.org