From predicting sounds to visualizing scenes

Researchers can feed the NAF visual information about a scene and a few spectrograms that show what a piece of audio would sound like when the emitter and listener are located at target locations around the room. Then the model predicts what that audio would sound like if the listener moves to any point in the scene.

The NAF outputs an impulse response, which captures how a sound should change as it propagates through the scene. The researchers then apply this impulse response to different sounds to hear how those sounds should change as a person walks through a room.

For instance, if a song is playing from a speaker in the center of a room, their model would show how that sound gets louder as a person approaches the speaker and then becomes muffled as they walk out into an adjacent hallway.

When the researchers compared their technique to other methods that model acoustic information, it generated more accurate sound models in every case. And because it learned local geometric information, their model was able to generalize to new locations in a scene much better than other methods.

Moreover, they found that applying the acoustic information their model learns to a computer vison model can lead to a better visual reconstruction of the scene.

“When you only have a sparse set of views, using these acoustic features enables you to capture boundaries more sharply, for instance. And maybe this is because to accurately render the acoustics of a scene, you have to capture the underlying 3D geometry of that scene,” Du says.

The researchers plan to continue enhancing the model so it can generalize to brand new scenes. They also want to apply this technique to more complex impulse responses and larger scenes, such as entire buildings or even a town or city.

“This new technique might open up new opportunities to create a multimodal immersive experience in the metaverse application,” adds Gan.

“My group has done a lot of work on using machine-learning methods to accelerate acoustic simulation or model the acoustics of real-world scenes. This paper by Chuang Gan and his co-authors is clearly a major step forward in this direction,” says Dinesh Manocha, the Paul Chrisman Iribe Professor of Computer Science and Electrical and Computer Engineering at the University of Maryland, who was not involved with this work. “In particular, this paper introduces a nice implicit representation that can capture how sound can propagate in real-world scenes by modeling it using a linear time-invariant system. This work can have many applications in AR/VR as well as real-world scene understanding.”

This work is supported, in part, by the MIT-IBM Watson AI Lab and the Tianqiao and Chrissy Chen Institute.