杏吧原创

In Harry Potter鈥檚 universe, people in portraits and pictures don鈥檛 just sit there. They smile, gasp, wink, or get up to mischief. Facebook has been hard at work making this a reality for your profile pic as well.

Their new tool only requires a single image of a face as input. From this, it is then able to create an animated version that puts on either a happy, sad, or angry expression. This is no mere animated gif 鈥� in theory, any expression could be聽 mapped to your face, including ones you would never think of making. The effect is sometimes a little strange to watch, but in a study half of the people who saw the animations were fooled into thinking that they were real.

鈥淲e鈥檝e shown that reactive profile pictures are possible,鈥� says at Tel Aviv University, who conducted the research as part of a collaboration with Facebook.

To create the animations, the tool uses a 鈥渂ase鈥� video of another completely different person. That person doesn鈥檛 have to be the same gender or look remotely similar. Their facial expression is mapped onto the still image and then warped so that it starts to look like an animated expression.

However, warping alone isn鈥檛 enough. When someone smiles they often go from not showing any teeth to revealing a set of pearly whites. However, from a single image, the system doesn鈥檛 necessarily know what the person鈥檚 teeth look like so it has to steal them from the helper video.

鈥淲e found that if we change the teeth people don鈥檛 notice too much,鈥� says Averbuch-Elor.

The聽team also showcased several ways Facebook could make use of these reactive profile pictures. For example, when someone clicks 鈥渓ike鈥� on a post the profile picture could smile in response.

Systems like this are improving all the time. 鈥淚 think eventually they will be completely indistinguishable from real videos,鈥� says Averbuch-Elor. In the future, the tool could be combined with natural language processing, so that when you are messaging with someone rather than a static image you see an animated version of the person reacting to what鈥檚 being said.

The project will be presented at the Conference on Techniques in Bangkok, Thailand later this month.