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Time-of-day perception in paintings

Yu, C. (author), Van Zuijlen, Mitchell J.P. (author), Spoiala, C. (author), Pont, S.C. (author), Wijntjes, M.W.A. (author), Hurlbert, Anya (author)

The spectral shape, irradiance, direction, and diffuseness of daylight vary regularly throughout the day. The variations in illumination and their effect on the light reflected from objects may in turn provide visual information as to the time of day. We suggest that artists' color choices for paintings of outdoor scenes might convey this...

journal article 2024

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Quantifying the spatial, temporal, angular and spectral structure of effective daylight in perceptually meaningful ways

Yu, C. (author), Wijntjes, M.W.A. (author), Eisemann, E. (author), Pont, S.C. (author)

We present a method to capture the 7-dimensional light field structure, and translate it into perceptually-relevant information. Our spectral cubic illumination method quantifies objective correlates of perceptually relevant diffuse and directed light components, including their variations over time, space, in color and direction, and the...

journal article 2023

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Effects of inter-reflections on the chromatic structure of the light field

Yu, C. (author), Eisemann, E. (author), Pont, S.C. (author)

Chromatic properties of the effective light in a space are hard to predict, measure and visualise. This is due to complex interactions between materials and illuminants. Here, we describe, measure and visualise the effects of inter-reflections on the structure of the physical light field for diffusely scattering scenes. The spectral...

journal article 2022

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Effects of inter-reflections on the correlated colour temperature and colour rendition of the light field: Inter-reflections and effective colour rendition

Yu, C. (author), Wijntjes, M.W.A. (author), Eisemann, E. (author), Pont, S.C. (author)

In everyday scenes, the effective light (the actual light in a space) can be defined as a complex light field, resulting from a mixture of emissive light sources and indirect mutual surface (inter-)reflections. Hence, the light field typically consists of diffuse and directional illumination and varies in spectral irradiance as a function of...

journal article 2022

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A juicy orange makes for a tastier juice: The neglected role of visual material perception in packaging design

Di Cicco, F. (author), Zhao, Y. (author), Wijntjes, M.W.A. (author), Pont, S.C. (author), Schifferstein, Hendrik N.J. (author)

Food appearance sets intentions and expectations. When designing packaged food much attention is devoted to packaging elements like color and shape, but less to the characteristics of the images used. To our awareness, no study has yet investigated how the appearance of the food shown on the package affects consumers’ preferences. Often, orange...

journal article 2021

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Soft like velvet and shiny like satin: Perceptual material signatures of fabrics depicted in 17th century paintings

Di Cicco, F. (author), van Zuijlen, M.J.P. (author), Wijntjes, M.W.A. (author), Pont, S.C. (author)

Dutch 17th century painters were masters in depicting materials and their properties in a convincing way. Here, we studied the perception of the material signatures and key image features of different depicted fabrics, like satin and velvet. We also tested whether the perception of fabrics depicted in paintings related to local or global cues,...

journal article 2021

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Materials in Paintings (MIP): An interdisciplinary dataset for perception, art history, and computer vision

van Zuijlen, M.J.P. (author), Lin, Hubert (author), Bala, Kavita (author), Pont, S.C. (author), Wijntjes, M.W.A. (author)

In this paper, we capture and explore the painterly depictions of materials to enable the study of depiction and perception of materials through the artists’ eye. We annotated a dataset of 19k paintings with 200k+ bounding boxes from which polygon segments were automatically extracted. Each bounding box was assigned a coarse material label (e...

journal article 2021

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Painterly depiction of material properties

van Zuijlen, M.J.P. (author), Pont, S.C. (author), Wijntjes, M.W.A. (author)

Painters are masters of depiction and have learned to evoke a clear perception of materials and material attributes in a natural, three-dimensional setting, with complex lighting conditions. Furthermore, painters are not constrained by reality, meaning that they could paint materials without exactly following the laws of nature, while still...

journal article 2020

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If painters give you lemons, squeeze the knowledge out of them: A study on the visual perception of the translucent and juicy appearance of citrus fruits in paintings

Di Cicco, F. (author), Wijntjes, M.W.A. (author), Pont, S.C. (author)

Citrus fruits are characterized by a juicy and translucent interior, important properties that drive material recognition and food acceptance. Yet, a thorough understanding of their visual perception is still missing. Using citrus fruits depicted in 17th-century paintings as stimuli, we ran three rating experiments. In Experiment 1,...

journal article 2020

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Material properties and image cues for convincing grapes: The know-how of the 17th-century pictorial recipe by Willem Beurs

Di Cicco, F. (author), Wiersma, Lisa (author), Wijntjes, M.W.A. (author), Pont, S.C. (author)

Painters mastered replicating the regularities of the visual patterns that we use to infer different materials and their properties, via meticulous observation of the way light reveals the world's textures. The convincing depiction of bunches of grapes is particularly interesting. A convincing portrayal of grapes requires a balanced...

journal article 2020

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Effects of light map orientation and shape on the visual perception of canonical materials

Zhang, F. (author), de Ridder, H. (author), Barla, Pascal (author), Pont, S.C. (author)

We previously presented a systematic optics-based canonical approach to test material-lighting interactions in their full natural ecology, combining canonical material and lighting modes. Analyzing the power of the spherical harmonics components of the lighting allowed us to predict the lighting effects on material perception for generic...

journal article 2020

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Understanding gloss perception through the lens of art: Combining perception, image analysis, and painting recipes of 17th century painted grapes

Di Cicco, F. (author), Wijntjes, M.W.A. (author), Pont, S.C. (author)

To understand the key image features that we use to infer the glossiness of materials, we analyzed the pictorial shortcuts used by 17th century painters to imitate the optical phenomenon of specular reflections when depicting grapes. Gloss perception of painted grapes was determined via a rating experiment. We computed the contrast, blurriness,...

journal article 2019

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Comparison of three 3D scanning techniques for paintings, as applied to Vermeer’s ‘Girl with a Pearl Earring’

Elkhuizen, W.S. (author), Dore-Callewaert, T.W.J. (author), Leonhardt, Emilien (author), Vandivere, Abbie (author), Song, Y. (author), Pont, S.C. (author), Geraedts, Jo M.P. (author), Dik, J. (author)

A seventeenth-century canvas painting is usually comprised of varnish and (translucent) paint layers on a substrate. A viewer’s perception of a work of art can be affected by changes in and damages to these layers. Crack formation in the multi-layered stratigraphy of the painting is visible in the surface topology. Furthermore, the impact of...

journal article 2019

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A toolbox for volumetric visualization of light properties

Kartashova, T. (author), de Ridder, H. (author), te Pas, S. F. (author), Pont, S.C. (author)

In this paper, we introduce a toolbox for the perceptually based visualization of light in a volume, focusing on the visual effects of illumination. First, our visualizations extend the conventional methods from a two-dimensional representation on surfaces to the whole volume of a scene. Second, we extend the conventional methods from showing...

journal article 2019

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A systematic approach to testing and predicting light-material interactions

Zhang, F. (author), de Ridder, H. (author), Barla, Pascal (author), Pont, S.C. (author)

Photographers and lighting designers set up lighting environments that best depict objects and human figures to convey key aspects of the visual appearance of various materials, following rules drawn from experience. Understanding which lighting environment is best adapted to convey which key aspects of materials is an important question in...

journal article 2019

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Gloss, color and topography scanning for reproducing a painting’s appearance using 3D printing

Elkhuizen, W.S. (author), Essers, T.T.W. (author), Song, Y. (author), Geraedts, Jo M.P. (author), Weijkamp, Clemens (author), Dik, J. (author), Pont, S.C. (author)

High fidelity reproductions of paintings provide new opportunities to museums in preserving and providing access to cultural heritage. This paper presents an integrated system which is able to capture and fabricate color, topography and gloss of a painting, of which gloss capturing forms the most important contribution. A 3D imaging system,...

journal article 2019

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Visual Light Zones

Kartashova, T. (author), de Ridder, H. (author), te Pas, S.F. (author), Pont, S.C. (author)

In this article, we studied perception of a particular case of light fields that is characterized by a difference in its consistent structure between parts of a scene. In architectural lighting design, such a consistent structure in a part of a light field is called a light zone. First, we explored whether human observers are sensitive to...

journal article 2018

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Asymmetric perceptual confounds between canonical lightings and materials

Zhang, F. (author), de Ridder, H. (author), Pont, S.C. (author)

To better understand the interactions between material perception and light perception, we further developed our material probe MatMix 1.0 into MixIM 1.0, which allows optical mixing of canonical lighting modes. We selected three canonical lighting modes (ambient, focus, and brilliance) and created scenes to represent the three illuminations....

journal article 2018

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Colored backgrounds affect the attractiveness of fresh produce, but not it's perceived color

Schifferstein, Hendrik N.J. (author), Howell, BF (author), Pont, S.C. (author)

The color of the background on which products are presented may affect their perceived attractiveness. We presented five different vegetables (tomato, carrot, yellow bell pepper, cucumber, eggplant) on four different background colors (orange or blue, either light or dark). Although the backgrounds did not affect the direct color perception...

journal article 2017

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Separate and simultaneous adjustment of light qualities in a real scene

Xia, L. (author), Pont, S.C. (author), Heynderickx, I.E.J.R. (author)

Humans are able to estimate light field properties in a scene in that they have expectations of the objects' appearance inside it. Previously, we probed such expectations in a real scene by asking whether a "probe object" fitted a real scene with regard to its lighting. But how well are observers able to interactively adjust the light...

journal article 2017