Core Concepts
Neural noise can be leveraged to enable deep neural networks trained on generic image reconstruction tasks to perform unsupervised perceptual grouping and image segmentation.
Abstract
The authors propose a novel computational approach called Latent Noise Segmentation (LNS) that enables deep neural networks to perform unsupervised perceptual grouping and image segmentation. The key insight is that adding independent noise to the latent representation of a pre-trained autoencoder or variational autoencoder can reveal the local structure of the input data, allowing the model to separate objects from each other.
The authors first provide a mathematical analysis demonstrating that under realistic assumptions, neural noise can be used to separate objects in the input. They then show empirically that adding noise to the latent layer of a deep neural network enables the network to segment images, even though it was never trained on any segmentation labels.
To evaluate the performance of LNS, the authors introduce the Good Gestalt (GG) datasets, which are designed to test a model's ability to reproduce important phenomena in human perception, such as illusory contours, closure, continuity, proximity, and occlusion. The authors show that their LNS-enabled models are able to reproduce many of these Gestalt principles, outperforming other tested unsupervised models by 24.9% on average.
The authors further analyze the practical feasibility of LNS, investigating how segmentation performance varies with different model learning rules, noise levels, and the number of time steps the model takes to segment. They find that a practically feasible number of time steps (as few as a handful) are sufficient to reliably segment, and that while encouraging a prior distribution in the model does not improve its segmentation performance, it stabilizes the optimal amount of noise needed for segmentation across all datasets.
Overall, the authors present a novel unsupervised segmentation method that requires few assumptions, a new explanation for the formation of perceptual grouping, and a potential benefit of neural noise in deep neural networks.
Stats
"Neural noise can be used to separate objects from each other."
"Adding noise to the latent layer of a deep neural network enables the network to segment images, even though it was never trained on any segmentation labels."
"The authors' LNS-enabled models outperform other tested unsupervised models by 24.9% on average on the Good Gestalt (GG) datasets."
"A practically feasible number of time steps (as few as a handful) are sufficient to reliably segment."
"Encouraging a prior distribution in the model stabilizes the optimal amount of noise needed for segmentation across all datasets."
Quotes
"Neural noise can be used to separate objects from each other."
"Adding noise to the latent layer of a deep neural network enables the network to segment images, even though it was never trained on any segmentation labels."
"The authors' LNS-enabled models outperform other tested unsupervised models by 24.9% on average on the Good Gestalt (GG) datasets."