Pornhub has used artificial intelligence (AI) to remaster and colorize a series of historical erotic and porn films, dating back as far as 1896, to 4K, 60fps resolution.

The series, named [NSFW] Remastured, uses deep learning across Pornhub’s archive to allow the AI to become familiar with the most important recurring images.

“It is common practice in film to colorize and restore even the most antique footage. However, the algorithms generally available are lacking since standard deep-learning models are trained with millions of SFW images, not nude or even pornographic ones,” a Pornhub spokesperson said. “By introducing the AI to Pornhub’s massive content library, it learned a naughty new trick; how to detect the subtle shades of penises, nipples, and turn-of-the-century bush.”

Remastured features color versions of black and white shorts such as French film Le Coucher de la Mariée, or Bedtime for the Bride, which was first screened in 1896. It is considered to be one of the first erotic films, and features a woman undressing but no nudity.

An 1896 film, The Kiss, directed by Thomas Edison, credited with being the first film to capture a kiss, also features in the list. It has no nudity or overtly sexual content – it’s basically just an awkward kiss – but was denounced as obscene by many at the time. Kissing in public was illegal at the time.

That film is shortly followed by After The Ball, an 1897 short showing a woman undressing, filmed by influential French filmmaker Marie-Georges-Jean Méliès.

As the 20-film series continues through its timeline, the footage gets racier to correspond with society’s loosening views of sexuality and what was considered obscene. One film from 1920, The Hairdresser, features a topless woman brushing her hair.

Things get hardcore from 1908 in The Hotel D’or, which features an explicit threesome and innovative use of a vacuum cleaner.

The most recent film featured is Family Spirit, from 1948, by which time things had progressed massively since Edison et al’s early efforts. It features hardcore anal penetration and strap-ons.

Pornhub said the colorization process “utilized several AI algorithms with limited human intervention”. Footage was boosted to 60 frames per second and rescaled to 4K resolution. Other modernizing efforts included flicker reduction and audio remastering or replacement.

The colorization results are patchy, with the color tones of the footage often ebbing closer to black and white or sepia than full colour. But it’s an interesting endeavour, well-presented on an informative timeline, soundtracked by near-constant jaunty piano.

The project isn’t Pornhub’s first foray into historical erotica – in 2019 the site partnered with New York’s Museum of Sex for an exhibition entitled STAG: The Illicit Origins of Pornographic Film.

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