New insights on human perception set to boost computer graphics and design industries
Sight is a highly complex process. Now, one EU-funded project has advanced knowledge on our visual perceptions of shape, material properties and illumination, and uncovered results that can be used by a wide range of industries from computer graphics to car paints. The PRISM project’s findings can also inform guidelines for architectural lighting design. Uses range from basic safety, such as ensuring stairways and doors are clearly visible, to aesthetic lighting designs for commercial product displays, such as like lighting that maximises the lustre and glint of jewellery. Throughout the project, researchers discovered the intimate connections between the way the eye perceives shapes, material properties and light, and identified some of the visual cues that humans use to understand the physical properties of the surrounding world. For example, it found that humans can visually infer the properties of different liquids by watching how they move and change shape as they flow, ooze or splash. ‘We showed volunteers simulations of fluids with different viscosities flowing through various virtual scenes. By comparing the perception of the participants with computational analyses of simulations, we could identify specific geometrical features that observers use to make their judgements,’ says Roland Fleming, PRISM project coordinator. PRISM also measured how humans perceive the distribution of light within complex scenes in computer simulations, real scenes and even paintings. The results revealed that humans have an incredibly rich representation of spatial light distributions – we don’t just perceive how much light there is but also the direction and quality of light. ‘Vision is challenging because the retinal images result from complex interactions between lighting, surfaces properties, shape and viewpoint. To interpret retinal images, so we can perceive the outside world, the visual system must somehow disentangle the different physical causes that make up the observed image,’ explains Fleming. Many of PRISM’s findings have direct implications for the computer graphics industry, and the pigment and printing industries. By identifying the perceptual cues that the visual system relies on, designers can develop leaner computer graphics that only reproduce the aspects of the image that drive human perception. Moreover, the perception of material properties, such as surface gloss, are of potential importance to the pigment and printing industries. Throughout the project, PRISM combined a set of innovative techniques from psychology, neuroscience, computer science and industrial design. ‘For example, so that we could study complex material properties in a controlled but physically realistic way, we used cutting-edge computer graphics simulations,’ says Fleming. PRISM also used innovative brain-scanning techniques such as Diffusion Tensor Imaging (DTI), which allowed it to investigate the connections between different brain areas and how these are used in different visual and learning tasks. With the project now over, the project’s industrial partners are taking findings forward in computer graphics, automotive, architectural and design industries. Researchers are now in the process of developing new standards that industrial partners will be able to use in the development and quality control of car paints, for example.
Keywords
PRISM, computer graphics, light, visual perception, shape, materials, paint, jewellery
