This Advanced Technology Turns Audio Into Visual Clips

Scientists have developed new computer algorithms that can turn audio clips into a realistic, lip-synced video of the person speaking those words.

The researchers successfully generated highly-realistic video of former US President Barack Obama talking about terrorism, fatherhood, job creation and other topics, using audio clips of those speeches and existing weekly video addresses that were originally on a different topic.

"These type of results have never been shown before," said Ira Kemelmacher-Shlizerman, an assistant professor at the University of Washington in the US.

"Realistic audio-to-video conversion has practical applications like improving video conferencing for meetings, as well as futuristic ones such as being able to hold a conversation with a historical figure in virtual reality by creating visuals just from audio," said Kemelmacher- Shlizerman.

In a visual form of lip-syncing, the system converts audio files of an individual's speech into realistic mouth shapes, which are then grafted onto and blended with the head of that person from another existing video.

The team chose Obama because the machine learning technique needs available video of the person to learn from, and there were hours of presidential videos in the public domain.

"In the future video, chat tools like Skype or Messenger will enable anyone to collect videos that could be used to train computer models," Kemelmacher-Shlizerman said.

Because streaming audio over the internet takes up far less bandwidth than video, the new system has the potential to end video chats that are constantly timing out from poor connections.

By reversing the process - feeding video into the network instead of just audio - the team could also potentially develop algorithms that could detect whether a video is real or manufactured, researchers said.

The new machine learning tool makes significant progress in overcoming what is known as the "uncanny valley" problem, which has dogged efforts to create realistic video from audio.

When synthesised human likenesses appear to be almost real - but still manage to somehow miss the mark - people find them creepy or off-putting.