Research in lightness perception centers on understanding the prior assumptions and processing strategies the visual system uses to parse the retinal intensity distribution (the proximal stimulus) into the surface reflectance and illumination components of the scene (the distal stimulus-ground truth). It is agreed that the visual system must compare different regions of the visual image to solv...

Lightness, or perceived reflectance of a surface, is influenced by surrounding context. This is demonstrated by the Simultaneous Contrast Illusion (SCI), where a gray patch is perceived lighter against a black background and vice versa. Conversely, assimilation is where the lightness of the target patch moves toward that of the bounding areas and can be demonstrated in White's effect. Blakeslee...

Asymmetric lightness matching was employed to measure how the visual system assigns lightness to surface patches seen through partially-transmissive surfaces. Observers adjusted the luminance of a comparison patch seen through transparency, in order to match the lightness of a standard patch seen in plain view. Plots of matched-to-standard luminance were linear, and their slopes were consistent...

Experiments have recently been reported in which a decisive change in perceived light~ess was produced by a change in perceived spatial position, with no important change in the retinal image. A number of previous studies had found Little or no such effect. Experiments of the kind that produced these effects and of the kind that do not produce these effects are presented here. The main differen...

The surface reflectance of objects is highly variable, ranging between 4% for, say, charcoal and 90% for fresh snow. When stimuli are presented simultaneously, people can discriminate hundreds of levels of visual intensity. Despite this, human languages possess a maximum of just three basic terms for describing lightness. In English, these are white (or light), black (or dark), and gray. Why sh...

Many standard computer vision algorithms depend upon the solution of Poisson equations, retinex lightness computation being one such algorithm. Using lightness as an example, we show how it can be computed on a varying resolution sensor so long as the sensor architecture is based on a conformal mapping. We develop the varying resolution lightness algorithm by the well known technique of using a...

Although lightness perception is clearly influenced by contextual factors, it is not known whether knowledge about the reflectance of specific objects also affects their lightness. Recent research by O. H. MacLin and R. Malpass (2003) suggests that subjects label Black faces as darker than White faces, so in the current experiments, an adjustment methodology was used to test the degree to which...

When the illumination of a visual scene changes, the quantity of light reflected from objects is altered. Despite this, the perceived lightness of the objects generally remains constant. This perceptual lightness constancy is thought to be important behaviorally for object recognition. Here we show that interactions from outside the classical receptive fields of neurons in primary visual cortex...

There is a large literature characterizing human perception of the lightness and color of matte surfaces arranged in coplanar arrays. In the past ten years researchers have begun to examine perception of lightness and color using wider ranges of stimuli intended to better approximate the conditions of everyday viewing. One emerging line of research concerns perception of lightness and color in ...

Color of broiler skin was evaluated after exposure to organic acids under various concentrations and simulated potential plant application conditions. Breast skin from chilled broiler carcasses was treated with acetic (AA), citric (CA), lactic (LA), malic (ML), mandelic (MN), propionic (PA), or tartaric (TA) acids at 0.5, 1, 2, 4, and 6% concentrations. Each acid and concentration was applied i...