As the story goes, in the 1600s Rembrandt was commissioned by the Amsterdam civic guard to create a sweeping oil painting for their headquarters. The Dutch portraitist constructed a scene with the city’s mayor and his lieutenant—plus 32 other characters, including a dressed-up young lass. The piece is thought to have been completed in 1642, and was moved to the town hall in 1715. Rembrandt was long dead at this point. Without his guidance, the new handlers decided to make a few “edits” to get the painting to their liking: They shaved off a few sections (and subjects) from each of the sides to fit and mount the canvas.
Lucky for art appreciators today, the city commissioned another local painter to draw a smaller reference for the “Night Watch” prior to the hack job. The restoration scientists at Rijksmuseum tapped a form of AI known as neural networks to scale the missing elements from the copy to the original. Another set of algorithms helped them match Rembrandt’s signature light-and-shadow style as they “extended’ the piece back to its full form.
Source : https://www.popsci.com/science/rembrandt-night-watch-restoration-artificial-intelligence/