Scientists develop new noise-cancelling app which can block out ‘selected’ sounds while allowing others through

There may be times in life when you want to block out your partner's noise for half an hour.

Or maybe you hate the sound of your vacuum cleaner when you take a closer look at your home. Now scientists have developed an app that, when used alongside noise-cancelling headphones, can 'filter' out certain sounds and let other sounds through.

The algorithm can be programmed to block out all noise except specific sounds, such as a crying baby. The headphones stream audio to a smartphone, where a system processes them at high speed.

The app then plays only 'selected' sound – and that in less than a hundredth of a second. Tests in offices, streets and parks have shown that it is able to extract sirens, bird sounds and alarm signals while removing all other sounds from the real world. In one demonstration, a researcher was able to drown out the sound of his vacuum cleaner while still hearing a knock on the door.

The University of Washington team said there were cases where the system had difficulty distinguishing between similar sounds, such as vocal music and speech.

But they hope that training their model with more data could improve this, and plan to release a commercial version for use with standard noise-canceling headphones.

Professor Shyam Gollakota, author of the study presented at the User Interface Software and Technology Symposium in San Francisco, said he would use the technology to listen to nature in a park while “suppressing the chatter of people or traffic.”