The perception of depth from retinal images depends on information from multiple visual cues. One potential depth cue is the statistical relationship between luminance and distance; darker points in a local region of an image tend to be farther away than brighter points. We establish that this statistical relationship acts as a quantitative cue to depth. We show that luminance variations affect depth in naturalistic scenes containing multiple cues to depth. This occurred when the correlation between variations of luminance and depth was manipulated within an object, but not between objects. This is consistent with the local nature of the statistical relationship in natural scenes. We also showed that perceived depth increases as contrast is increased, but only when the depth signalled by luminance and binocular disparity are consistent. Our results show that the negative correlation between luminance and distance, as found under diffuse lighting, provides a depth cue that is combined with depth from binocular disparity, in a way that is consistent with the simultaneous estimation of surface depth and reflectance variations. Adopting more complex lighting models such as ambient occlusion in computer rendering will thus contribute to the accuracy as well as the aesthetic appearance of three-dimensional graphics.
|Number of pages||16|
|Journal||Royal Society Open Science|
|Publication status||Published - 15 Feb 2023|
- Psychology and cognitive neuroscience
- Research articles
- image statistics
- binocular disparity
- shape from shading
Supplementary material from "Luminance contrast provides metric depth information"
Hibbard, P. B., Goutcher, R., Hornsey, R. L., Hunter, D. & Scarfe, P., The Royal Society, 03 Feb 2023