FeIn art history, it is commonly accepted that the Flemish painter Jan Van Eyck ignored the laws of perspective. Gilles Simon, lecturer at the University of Lorraine and researcher at the LORIA computer science laboratory (CNRS, Inria, University of Lorraine), has carried out a probabilistic analysis of five paintings by the artist between 1432 and 1439 and has revealed, thanks to computer vision methods, that the painter was actually far ahead of his time. He used an advanced perspective machine with two degrees of freedom to represent space as closely as possible to human vision. This astonishing discovery solves a major enigma in the history of art and makes Jan Van Eyck the father of techniques such as augmented reality or synthetic holography.
Perspective: a history of depth
Perspective is the technique of representing objects in three dimensions on a flat surface by giving them an effect of depth. During the Renaissance, linear perspective revolutionized Italian painting, notably with Giotto and the notions of convergence point and horizon line. In 1425, the architect Filippo Brunelleschi invented the first augmented reality device, a wooden panel with an eyepiece, called Tavoletta. Finally, Leon Battista Alberti confirms these notions in 1436 in his treatise De Pictura, in which he evokes orthogonals joining in a single point. It is considered that the Italian painters were a step ahead of their Flemish counterparts.
Perspective in Jan Van Eyck
Jan Van Eyck marked the history of art by his meticulousness and his technique of oil painting, of which he was one of the precursors. His science of detail and his desire to immerse the viewer in the scene made him one of the great masters of the Renaissance. The question of perspective in Jan van Eyck’s work has been the subject of lively debate among art historians for the past hundred years. According to Erwin Panofsky, a specialist in Flemish primitive painters, the artist used perspective empirically and did not know its laws. It was while admiring the Ghent Altarpiece that Gilles Simon, a researcher specializing in augmented reality, was intrigued by a perspective that seemed particularly elaborate. He therefore decided to study the painter’s paintings, in particular The Arnolfini couple, more closely, at the crossroads of art history, geometry and probability.
An art historical enigma elucidated by computer science
The researcher proceeded to an analysis of the vanishing points. In order to corroborate his intuitions, Gilles Simon wanted to bring an objective point of view, thanks to mathematical tools. “Usually used to detect vanishing points in a photograph, the a-contrario model is a key technique in computer vision. I adapted it to the specificities of the painting and coupled it with a probabilistic consistency criterion,” explains Gilles Simon. His results showed four centric points regularly distributed along an inclined axis, and a fishbone pattern, common to all five paintings, which thus refutes any idea of chance.The 3D reconstruction of the painting allowed the researcher to deduce not only the way Van Eyck painted (strip by strip, through a glass or a mirror), but also his position (sitting, then standing). It seems that the painter also wanted to take into account the human stereoscopic vision in his paintings,” says Gilles Simon. These results show that the painter invented natural polyscopic perspective with an optical device comprising four eyelets, to represent the scene from different points of view while introducing the least possible perspective distortion.”
These analyses prove that Jan Van Eyck had created a revolutionary polyscopic perspective machine at the same time as the Italians invented monoscopic artificial perspective and 70 years before Leonardo da Vinci discovered a simplified version of the process. This discovery refutes all the theories established for 100 years about Jan Van Eyck’s perspectival system and opens new perspectives in art history. A paper presented at the international conference SIGGRAPH 2021Gilles Simon’s scientific paper, Jan van Eyck’s perspectival system elucidated through computer vision, has been selected for presentation at SIGGRAPH 2021, the leading international conference on computer graphics and interactive techniques, held August 9-13, 2021.