-photo by Kartic Subr
Introduction to Computer Graphics-
Perception IS Data?
28 July 2003
SIGGRAPH start? If you are the conference chair, it starts two
years in advance. If you are only coming for the exhibition,
SIGGRAPH begins when the Main Exhibition Hall Opens. For those
who come early and register for the full conference, the courses
provide interesting knowledge and instruction unlike that provided
in a paper or classroom. On the opening day of SIGGRAPH 2004,
just before virgin SIGGRAPH attendees were overwhelmed by all
the technology, art and stunning research, Michael Bailey drew
the audience's attention with his quote "Perception is data".
That raises a very important point- do we finally want to display
what IS, or what makes us perceive the "IS" ?
to Computer Graphics" course appeared to be a popular venue
on the first day of SIGGRAPH '03. CG rookies flocked to rooms
14 A-B at the San Diego Convention Center to attend this course
which was organized by Michael Bailey from the San Diego Supercomputer
Center.The two lecturers were Bailey and Andrew Glassner, from
Coyote Wind Studios The planning committee did well to make this
the only course open to all SIGGRAPH attendees.
with an introduction to the graphics process, the two speakers
enlightened the audience. The goals of the course were indeed
achieved when light was thrown on fundamental concepts in CG
such as modeling, rendering and animation. The other sections
covered in the course were Graphics Display Hardware and Scientific
Visualization. The course was concluded by a crisp and informative "How
to Attend SIGGRAPH" session. The day-long course was a good
blend of technical details, interesting applications and witty
management staff probably regretted not having planned enough
seating for this course and it did not appear to be their fault.
This session was educative to the average rookie, touching upon
application areas such as medicine, geology and engineering.
software that he used in his teaching, Bailey demonstrated effects
such as the "Row of Corn", different projection techniques
and volume visualization with range sliders to control the opacity.
Perception? Why Bother?
his talk on scientific visualization, mentioned the importance
of understanding the way we perceive visualized data."There
is a huge range of techniques that we could apply to change the
way we perceive data; the first step is to understand them.",
he said. He also explained that this was because of the anomalies
in the human perception system. As a simple example, he used
the traditional Mach bands to support "Our eyes do not see
absolute color; only relative color...". Both speakers demonstrated
several examples of optical illusions, eliciting a spectrum of
responses- from the "Yea, I've seen this one before" smile
to "Now you're kidding me!" exclamations.
correctness, precision and accuracy are extremely important in
Scientific Visualization, if the resulting visualization is going
to be perceived and interpreted by a human, should we apply techniques
based on our understanding of the human perceptual system that
will make interpretation of the data correct? Would this in turn
affect the effectiveness of visualization as a tool for data
interpretation? Those were some of the questions ringing in the
heads of the audience by the end of the talk. The speakers were
also kind enough to talk to the long line of people who were
asking questions or looking for advice.