How watching Pixar revealed the dark side of gloss

Two red dragons, one completely matte (left), and one glossy (right). The dragon on the right appears compellingly glossy especially in surface regions that generate lowlights, seen as locally dark surface regions that are not apparent on the matte counterpart. Credit: Juno Kim

(Medical Xpress)—A eureka moment while watching a movie for the umpteenth time with his children has led a University of Sydney researcher to achieve a new insight into visual perception, which could benefit traditional artists and graphic designers.

"I was watching the Pixar animation Cars with my kids for about the fiftieth time but this was the first time I noticed that the duco of one of the cars was attractively glossy even though it only reflected images of the dark trees in the background," said Dr Juno Kim, from the University's School of Psychology and the lead author of the study, published in this week.

The observation led Dr Kim and his colleagues to test the intuitive assumption that glossiness is the result of reflections of light off a that is smooth, shiny or wet.

The researchers added local dark or light areas to artificial two-dimensional surfaces, and asked study participants to report whether the surfaces looked glossy.

"We found that adding dark areas and bright areas to a matte surface could make the surface appear glossy. Importantly, even surfaces made up only of arrangements of dark regions created a compelling perception of glossiness," Dr Kim said.

Glossy surfaces can produce both bright highlights and dark 'lowlights' and the presence of either is enough for the human visual system to perceive the surface as being glossy.

The findings support earlier research led by Professor Bart Anderson, from the University's Surface Perception Laboratory, that the brain performs a complex geometric analysis and does not just do simple computations in order to perceive an object.

"In this case the brain works with the geometric relationships between locally dark or locally bright regions in the context of the surrounding shading," said Dr Kim.

The findings have implications for both computer graphics and for machine vision, (where machines perform repetitive human tasks with visual feedback).

While modern artists and computer designers, such as Pixar, have previously used the technique without knowing how or why it worked, the new findings could provide better applications.

"Future graphic packages could create algorithms that take advantage of this new information to give designers new options in simulating the glossy appearance of any material," Dr Kim said.

More information: www.nature.com/neuro/journal/v… nt/full/nn.3221.html

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nayTall
5 / 5 (3) Sep 26, 2012
how is this not extremely common knowledge? artists have been utilizing this method for realism for hundreds of years. why on earth were they studying only highlights previously?
Argiod
3.7 / 5 (3) Sep 27, 2012
Indeed, the Old Master oil painters knew this well. Maybe our scientists need to go to art school to catch up with what's already available in the way of knowledge of how light works to create the visual world around us.
joey12345
not rated yet Sep 27, 2012
"...computer designers, such as Pixar, have previously used the technique without knowing how or why it worked, the new findings could provide better applications."

Are you seriously trying to state that the last 30 years of development in rendering packages had no clue they were taking advantage of this centuries old technique?

Almost every high end software designed to render images from 3d scene descriptions has been carefully engineered around this and other well understood principles of visual perception.

This is a ridiculous claim at discovering something common place and well documented.