Separating the "Chirp" from the "Chat": Self-supervised Visual Grounding of Sound and Language
Authors: Mark Hamilton, Andrew Zisserman, John R. Hershey, William T. Freeman

We present DenseAV a novel dual encoder grounding architecture that learns high-resolution semantically meaningful and audio-visual aligned features solely through watching videos. We show that DenseAV can discover the "meaning" of words and the "location" of sounds without explicit localization supervision. Furthermore it automatically discovers and distinguishes between these two types of associations without supervision. We show that DenseAV's localization abilities arise from a new multi-head feature aggregation operator that directly compares dense image and audio representations for contrastive learning. In contrast many other systems that learn "global" audio and video representations cannot localize words and sound. Finally we contribute two new datasets to improve the evaluation of AV representations through speech and sound prompted semantic segmentation. On these and other datasets we show DenseAV dramatically outperforms the prior art on speech and sound prompted semantic segmentation. DenseAV outperforms the current state-of-the-art ImageBind on cross-modal retrieval using fewer than half of the parameters. Project Page: https://aka.ms/denseav