Facebook could secretly watch users through webcams, patent reveals

Facebook is considering secretly watching and recording users through their webcams and smartphone cameras, a newly discovered patent suggests.

The document explains how the company would use technology to see how your facial expressions change when you come across different types of content on the site.

It would analyse those images to work out how you feel, and use the information to keep you on the site for longer.

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1/43 Designed by Pierpaolo Lazzarini from Italian company Jet Capsule. The I.F.O. is fuelled by eight electric engines, which is able to push the flying object to an estimated top speed of about 120mph. Jet Capsule/Cover Images

2/43 A humanoid robot gestures during a demo at a stall in the Indian Machine Tools Expo, IMTEX/Tooltech 2017 held in Bangalore Getty Images

3/43 A humanoid robot gestures during a demo at a stall in the Indian Machine Tools Expo, IMTEX/Tooltech 2017 held in Bangalore Getty Images

4/43 Engineers test a four-metre-tall humanoid manned robot dubbed Method-2 in a lab of the Hankook Mirae Technology in Gunpo, south of Seoul, South Korea Jung Yeon-Je/AFP/Getty Images

5/43 Engineers test a four-metre-tall humanoid manned robot dubbed Method-2 in a lab of the Hankook Mirae Technology in Gunpo, south of Seoul, South Korea Jung Yeon-Je/AFP/Getty Images

6/43 The giant human-like robot bears a striking resemblance to the military robots starring in the movie 'Avatar' and is claimed as a world first by its creators from a South Korean robotic company Jung Yeon-Je/AFP/Getty Images

7/43 Engineers test a four-metre-tall humanoid manned robot dubbed Method-2 in a lab of the Hankook Mirae Technology in Gunpo, south of Seoul, South Korea Jung Yeon-Je/AFP/Getty Images

8/43 Waseda University's saxophonist robot WAS-5, developed by professor Atsuo Takanishi Rex

9/43 Waseda University's saxophonist robot WAS-5, developed by professor Atsuo Takanishi and Kaptain Rock playing one string light saber guitar perform jam session Rex

10/43 A test line of a new energy suspension railway resembling the giant panda is seen in Chengdu, Sichuan Province, China Reuters

11/43 A test line of a new energy suspension railway, resembling a giant panda, is seen in Chengdu, Sichuan Province, China Reuters

12/43 A concept car by Trumpchi from GAC Group is shown at the International Automobile Exhibition in Guangzhou, China Rex

13/43 A Mirai fuel cell vehicle by Toyota is displayed at the International Automobile Exhibition in Guangzhou, China Reuters

14/43 A visitor tries a Nissan VR experience at the International Automobile Exhibition in Guangzhou, China Reuters

15/43 A man looks at an exhibit entitled 'Mimus' a giant industrial robot which has been reprogrammed to interact with humans during a photocall at the new Design Museum in South Kensington, London Getty

16/43 A new Israeli Da-Vinci unmanned aerial vehicle manufactured by Elbit Systems is displayed during the 4th International conference on Home Land Security and Cyber in the Israeli coastal city of Tel Aviv Getty

17/43 Electrification Guru Dr. Wolfgang Ziebart talks about the electric Jaguar I-PACE concept SUV before it was unveiled before the Los Angeles Auto Show in Los Angeles, California, U.S Reuters

18/43 The Jaguar I-PACE Concept car is the start of a new era for Jaguar. This is a production preview of the Jaguar I-PACE, which will be revealed next year and on the road in 2018 AP

19/43 Japan's On-Art Corp's CEO Kazuya Kanemaru poses with his company's eight metre tall dinosaur-shaped mechanical suit robot 'TRX03' and other robots during a demonstration in Tokyo, Japan Reuters

20/43 Japan's On-Art Corp's eight metre tall dinosaur-shaped mechanical suit robot 'TRX03' Reuters

21/43 Japan's On-Art Corp's eight metre tall dinosaur-shaped mechanical suit robot 'TRX03' performs during its unveiling in Tokyo, Japan Reuters

22/43 Singulato Motors co-founder and CEO Shen Haiyin poses in his company's concept car Tigercar P0 at a workshop in Beijing, China Reuters

23/43 The interior of Singulato Motors' concept car Tigercar P0 at a workshop in Beijing, China Reuters

24/43 Singulato Motors' concept car Tigercar P0 Reuters

25/43 A picture shows Singulato Motors' concept car Tigercar P0 at a workshop in Beijing, China Reuters

26/43 Connected company president Shigeki Tomoyama addresses a press briefing as he elaborates on Toyota's "connected strategy" in Tokyo. The Connected company is a part of seven Toyota in-house companies that was created in April 2016 Getty

27/43 A Toyota Motors employee demonstrates a smartphone app with the company's pocket plug-in hybrid (PHV) service on the cockpit of the latest Prius hybrid vehicle during Toyota's "connected strategy" press briefing in Tokyo Getty

28/43 An exhibitor charges the battery cells of AnyWalker, an ultra-mobile chasis robot which is able to move in any kind of environment during Singapore International Robo Expo Getty

29/43 A robot with a touch-screen information apps stroll down the pavillon at the Singapore International Robo Expo Getty

30/43 An exhibitor demonstrates the AnyWalker, an ultra-mobile chasis robot which is able to move in any kind of environment during Singapore International Robo Expo Getty

31/43 Robotic fishes swim in a water glass tank displayed at the Korea pavillon during Singapore International Robo Expo Getty

32/43 An employee shows a Samsung Electronics' Gear S3 Classic during Korea Electronics Show 2016 in Seoul, South Korea Reuters

33/43 Visitors experience Samsung Electronics' Gear VR during the Korea Electronics Grand Fair at an exhibition hall in Seoul, South Korea Getty

34/43 Amy Rimmer, Research Engineer at Jaguar Land Rover, demonstrates the car manufacturer's Advanced Highway Assist in a Range Rover, which drives the vehicle, overtakes and can detect vehicles in the blind spot, during the first demonstrations of the UK Autodrive Project at HORIBA MIRA Proving Ground in Nuneaton, Warwickshire PA wire

35/43 Chris Burbridge, Autonomous Driving Software Engineer for Tata Motors European Technical Centre, demonstrates the car manufacturer's GLOSA V2X functionality, which is connected to the traffic lights and shares information with the driver, during the first demonstrations of the UK Autodrive Project at HORIBA MIRA Proving Ground in Nuneaton, Warwickshire PA wire

36/43 Ford EEBL Emergency Electronic Brake Lights is demonstrated during the first demonstrations of the UK Autodrive Project at HORIBA MIRA Proving Ground in Nuneaton, Warwickshire PA

37/43 Full-scale model of 'Kibo' on display at the Space Dome exhibition hall of the Japan Aerospace Exploration Agency (JAXA) Tsukuba Space Center, in Tsukuba, north-east of Tokyo, Japan EPA

38/43 Miniatures on display at the Space Dome exhibition hall of the Japan Aerospace Exploration Agency (JAXA) Tsukuba Space Center, in Tsukuba, north-east of Tokyo, Japan. In its facilities, JAXA develop satellites and analyse their observation data, train astronauts for utilization in the Japanese Experiment Module 'Kibo' of the International Space Station (ISS) and develop launch vehicles EPA

39/43 The robot developed by Seed Solutions sings and dances to the music during the Japan Robot Week 2016 at Tokyo Big Sight. At this biennial event, the participating companies exhibit their latest service robotic technologies and components Getty

40/43 The robot developed by Seed Solutions sings and dances to music during the Japan Robot Week 2016 at Tokyo Big Sight Getty

41/43 Government and industry are working together on a robot-like autopilot system that could eliminate the need for a second human pilot in the cockpit AP

42/43 Aurora Flight Sciences' technicians work on an Aircrew Labor In-Cockpit Automantion System (ALIAS) device in the firm's Centaur aircraft at Manassas Airport in Manassas, Va. AP

43/43 Flight Simulator Stefan Schwart and Udo Klingenberg preparing a self-built flight simulator to land at Hong Kong airport, from Rostock, Germany EPA

If you smiled as you looked at pictures of one of your friends, for instance, Facebook’s algorithm would take note of that and display more pictures of that friend in your News Feed.

Another example included in the patent application explains that if you looked away from your screen when a video of a kitten played, Facebook would stop showing similar type of videos in your Feed.

In another case, the document says that if you happened to watch an advert for scotch, Facebook could choose to target you with more adverts for scotch.

The patent application was submitted in February 2014 and published in August 2015, but was only recently spotted, by CBInsights.

"We often seek patents for technology we never implement, and patents should not be taken as an indication of future plans,” said a Facebook spokesperson.

However, the document raises yet more concern about a company that, in 2014, was found to have secretly manipulated hundreds of thousands of users’ News Feeds as part of an experiment to work out whether it could affect people’s emotions.

The company later admitted that it “failed to communicate clearly why and how we did it”.

Last year, a picture posted by Mark Zuckerberg showed that he covers his webcam and microphone with tape. The public rather predictably made a big deal out of it, and the discovery of Facebook’s patent will only fuel speculation.

The site isn’t believed to have put its plans into action yet, and there’s no guarantee that it ever will.

The patent also details a new text-messaging platform that would detect how hard you type, and use that information to attempt to work out how you feel.