There's a long-standing misconception that while photos are now incredibly easy to manipulate, video content is more likely to be genuine, because of how incredibly complicated it can be to make realistic edits to film. We all know that in real life, Hollywood actors look nothing like they do on magazine covers, but when it comes to them acting on film, what you see is pretty much what you get, right?

Well, not even close. Tech-savvy companies are making millions by realistically tweaking how actors - both male and female - look on your cinema and television screens. "Nobody looks like what you see on TV and in the movies. Everybody is altered," Claus Hansen from Method Studios in Los Angeles, one of the pioneers of video retouching technology, told Mashable back in 2014

And it's not just Hollywood that's surreptitiously tricking us regular folk into thinking their actors really are that perfect. Pretty soon we're going to have to cast a skeptical eye on every piece of video footage out there, because, as an international team of researchers has demonstrated in the video above, their new software gives them the freedom to make Donald Trump, George W. Bush, and Vladamir Putin say anything.

Computer scientists from Stanford University in the US, and the Max Planck Institute and University of Erlangen-Nuremberg in Germany, have developed software that can control the face of anyone in any video, by superimposing someone else's mouth onto the subject - sort of like a way more sophisticated version of Face Swap.

The software works with any type of camera and any recorded video. 

"Using advanced facial recognition, it looks at about 15 seconds of any face in a video and creates a 3D model of that face in real time," Adam Freelander reports for Quartz. "The result is incredibly realistic, as you can see (ahem) in the video above." (We see what you did there.)

As the researchers demonstrate, if you can find a footage of a person making a variety of expressions as they speak - Bush smiles and moves his mouth around a lot of in the clip they show - you can make the effect scarily convincing.

The only problem is when you come across someone like Vladimir Putin, who hates smiling even more than he hates planting trees, which means the talking face that's being superimposed onto his face in the footage will look frighteningly off when it smiles. 

While it looks like a bit of fun, once technology like this makes it out to the masses, it has the potential to change everything. We can no longer trust the validity of any image put in front of us, and pretty soon, every clip of a world leader speaking will be up for debate too.

So be ready for it. Don't believe what you watch, it could be shopped - you'll know because of the pixels and the way it is.