On the Ambient Optic Array: James Gibson's Insights About the Phenomenon of Chiaroscuro

Abstract

In 1966, James Gibson first presented his theory of the ambient optic array, and he proposed a new field of ecological optics that he hoped would advance our knowledge on this topic. This study will consider how his ideas have largely come to fruition over the past 50 years. It reviews the research on the visual perception of three-dimensional shape from shading, the effects of ambient light from surface interreflections on observers' perceptions, the perception of the light field, and the perception of surface materials. Finally, it also considers Gibson's impact on these developments.

Keywords: contours/surfaces; shapes/objects; surfaces/materials; three-dimensional perception.

Figure 1.

Pure radiant light in a room. Adapted from Gibson (1966).

Figure 2.

Reflected light from facing surfaces. Adapted from Gibson (1966).

Figure 3.

Scattering patterns for matte and partially polished surfaces. Adapted from Gibson (1966).

Figure 4.

Sampling the convergent rays at multiple vantage points. Adapted from Gibson (1966).

Figure 5.

An aerial photo of a hilly terrain. The variations of surface orientation produce gradients of intensity in the pattern of luminance.

Figure 6.

An image of two balls created by Todd & Mingolla (1983).

Figure 7.

The first computed image that incorporated global illumination. Adapted from Moon & Spencer (1948).

Figure 8.

Effects of vignetting and indirect illumination. Both surfaces are illuminated by a diffuse overhead source. The surface on the left has a reflectance of 0.5 and the one on the right has a reflectance of 0.9.

Figure 9.

Four images of a white room with varying degrees of interreflection. Moving clockwise from the upper left, the images were rendered 1, 5, 10 and 15 indirect bounces, respectively.

Figure 10.

Effects of shadows and indirect illumination on the perception of surface contact.

Figure 11.

Some stimulus probe locations for Koenderink et al. (2007).

Figure 12.

Errors with volumetric shadows. The left panel shows the correct setting and the right panel shows the average observer setting.

Figure 13.

A 3D scene used by Kartashova et al. (2016; left panel) and a sample of the probe regions (right panel).

Figure 14.

The light fields obtained by Kartashova et al. (2016) for physical measures (Left) and perceptual measures (Right). The depicted tubes point in the maximum direction of luminous flux at each location, and the intensity of the light is inversely proportional to the width of the tube.

Figure 15.

In order for regions of high contrast in an image to be perceived as specular highlights, they must be aligned appropriately with directions of minimum curvature on a surface.

Figure 16.

Images of a single object with different patterns of illumination and different surface materials. the top row from left to right depicts shiny white plastic, metal and glass. The bottom row depicts black velvet, satin and wax.