Spatial filtering, color constancy, and the color-changing dress

Abstract

The color-changing dress is a 2015 Internet phenomenon in which the colors in a picture of a dress are reported as blue-black by some observers and white-gold by others. The standard explanation is that observers make different inferences about the lighting (is the dress in shadow or bright yellow light?); based on these inferences, observers make a best guess about the reflectance of the dress. The assumption underlying this explanation is that reflectance is the key to color constancy because reflectance alone remains invariant under changes in lighting conditions. Here, we demonstrate an alternative type of invariance across illumination conditions: An object that appears to vary in color under blue, white, or yellow illumination does not change color in the high spatial frequency region. A first approximation to color constancy can therefore be accomplished by a high-pass filter that retains enough low spatial frequency content so as to not to completely desaturate the object. We demonstrate the implications of this idea on the Rubik's cube illusion; on a shirt placed under white, yellow, and blue illuminants; and on spatially filtered images of the dress. We hypothesize that observer perceptions of the dress's color vary because of individual differences in how the visual system extracts high and low spatial frequency color content from the environment, and we demonstrate cross-group differences in average sensitivity to low spatial frequency patterns.

Global depth perception alters local timing sensitivity

“…More broadly, the coarse-to-fine spatial influences on the present TOJ task align with the coarse-to-fine spatial influences demonstrated for diverse visual phenomena. These https://doi.org/10.1371/journal.pone.0228080.g010 phenomena include stereoscopic depth perception [46][47][48][49], hysteresis in motion perception [50], brightness illusions [51,52], and "the dress" color illusion [53]. Moreover, our results extend the recent coarse-to-fine motion demonstrations in which global direction reversals masked local color and orientation changes [5,6].…”

Stripping #The Dress: the importance of contextual information on inter-individual differences in colour perception

“…A priori, our study was not designed to explain how context affects colour perception of the ambiguous Dress image. To this goal, different hypotheses have been proposed to explain the Dress illusion (e.g., Dixon & Shapiro, 2017;Hesslinger & Carbon, 2016;Witzel et al, 2017). Nevertheless, our results would invite for further investigation of contrast information (i.e., contrast between light and dark parts of the ambiguous Dress picture) as a potential explanatory factor for the Dress illusion.…”

“…In the initial Internet survey of about three million respondents, 68% of the respondents indicated seeing the ambiguous Dress picture as W&G and 32% of the respondents as B&B in a forced-choice situation (Holderness, 2015). Subsequent studies reported a higher proportion of W&G viewers (Dixon & Shapiro, 2017;Mahroo et al, 2017;Moccia et al, 2016;Wallisch, 2017;Witzel, Racey, & O'Regan, 2017), a higher proportion of B&B viewers (Chetverikov & Ivanchei, 2016;Lafer-Sousa et al, 2015), or an equal split between the two viewer types (Aston & Hurlbert, 2017;Chetverikov & Ivanchei, 2016;Hesslinger & Carbon, 2016;Karlsson & Allwood, 2016;Schlaffke et al, 2015;Vemuri et al, 2016;Winkler, Spillmann, Werner, & Webster, 2015) using forced-choice and free naming paradigms. In studies that went beyond the possibility of two viewer types, mainly using freenaming paradigms to assess the colours of the ambiguous Dress picture, an intermediate variant of the Dress perception emerged -participants reported seeing the Dress as blue and brown/gold (B&Br) (Aston & Hurlbert, 2017;Lafer-Sousa et al, 2015;Mahroo et al, 2017;Wallisch, 2017;Witzel et al, 2017).…”

#TheDress: Categorical perception of an ambiguous color image

“…W/G reporters often identified regions in the center of the image, away from the warm background. Curiously, the most common region identified across all subjects tended to cover a large area of uniform color (B/K: the broad blue shoulder; W/G: the wide dark stripe), perhaps reflecting the importance of low spatial frequencies in color constancy (Dixon & Shapiro, 2017 ). Although these analyses suggest that bottom-up factors shape how we see the dress, it is possible that where subjects say they look is caused by how they see the dress's colors.…”