Learning Normal Flow Directly From Event Neighborhoods

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Yuan, Dehao, Burner, Levi, Wu, Jiayi, Liu, Minghui, Chen, Jingxi, Aloimonos, Yiannis, Fermüller, Cornelia
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913613473644544
author Yuan, Dehao
Burner, Levi
Wu, Jiayi
Liu, Minghui
Chen, Jingxi
Aloimonos, Yiannis
Fermüller, Cornelia
author_facet Yuan, Dehao
Burner, Levi
Wu, Jiayi
Liu, Minghui
Chen, Jingxi
Aloimonos, Yiannis
Fermüller, Cornelia
contents Event-based motion field estimation is an important task. However, current optical flow methods face challenges: learning-based approaches, often frame-based and relying on CNNs, lack cross-domain transferability, while model-based methods, though more robust, are less accurate. To address the limitations of optical flow estimation, recent works have focused on normal flow, which can be more reliably measured in regions with limited texture or strong edges. However, existing normal flow estimators are predominantly model-based and suffer from high errors. In this paper, we propose a novel supervised point-based method for normal flow estimation that overcomes the limitations of existing event learning-based approaches. Using a local point cloud encoder, our method directly estimates per-event normal flow from raw events, offering multiple unique advantages: 1) It produces temporally and spatially sharp predictions. 2) It supports more diverse data augmentation, such as random rotation, to improve robustness across various domains. 3) It naturally supports uncertainty quantification via ensemble inference, which benefits downstream tasks. 4) It enables training and inference on undistorted data in normalized camera coordinates, improving transferability across cameras. Extensive experiments demonstrate our method achieves better and more consistent performance than state-of-the-art methods when transferred across different datasets. Leveraging this transferability, we train our model on the union of datasets and release it for public use. Finally, we introduce an egomotion solver based on a maximum-margin problem that uses normal flow and IMU to achieve strong performance in challenging scenarios.
format Preprint
id arxiv_https___arxiv_org_abs_2412_11284
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Learning Normal Flow Directly From Event Neighborhoods
Yuan, Dehao
Burner, Levi
Wu, Jiayi
Liu, Minghui
Chen, Jingxi
Aloimonos, Yiannis
Fermüller, Cornelia
Computer Vision and Pattern Recognition
Event-based motion field estimation is an important task. However, current optical flow methods face challenges: learning-based approaches, often frame-based and relying on CNNs, lack cross-domain transferability, while model-based methods, though more robust, are less accurate. To address the limitations of optical flow estimation, recent works have focused on normal flow, which can be more reliably measured in regions with limited texture or strong edges. However, existing normal flow estimators are predominantly model-based and suffer from high errors. In this paper, we propose a novel supervised point-based method for normal flow estimation that overcomes the limitations of existing event learning-based approaches. Using a local point cloud encoder, our method directly estimates per-event normal flow from raw events, offering multiple unique advantages: 1) It produces temporally and spatially sharp predictions. 2) It supports more diverse data augmentation, such as random rotation, to improve robustness across various domains. 3) It naturally supports uncertainty quantification via ensemble inference, which benefits downstream tasks. 4) It enables training and inference on undistorted data in normalized camera coordinates, improving transferability across cameras. Extensive experiments demonstrate our method achieves better and more consistent performance than state-of-the-art methods when transferred across different datasets. Leveraging this transferability, we train our model on the union of datasets and release it for public use. Finally, we introduce an egomotion solver based on a maximum-margin problem that uses normal flow and IMU to achieve strong performance in challenging scenarios.
title Learning Normal Flow Directly From Event Neighborhoods
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2412.11284