Leveraging Sparse LiDAR for RAFT-Stereo: A Depth Pre-Fill Perspective

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Yoo, Jinsu, Jeon, Sooyoung, Huang, Zanming, Pan, Tai-Yu, Chao, Wei-Lun
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916864974651392
author Yoo, Jinsu
Jeon, Sooyoung
Huang, Zanming
Pan, Tai-Yu
Chao, Wei-Lun
author_facet Yoo, Jinsu
Jeon, Sooyoung
Huang, Zanming
Pan, Tai-Yu
Chao, Wei-Lun
contents We investigate LiDAR guidance within the RAFT-Stereo framework, aiming to improve stereo matching accuracy by injecting precise LiDAR depth into the initial disparity map. We find that the effectiveness of LiDAR guidance drastically degrades when the LiDAR points become sparse (e.g., a few hundred points per frame), and we offer a novel explanation from a signal processing perspective. This insight leads to a surprisingly simple solution that enables LiDAR-guided RAFT-Stereo to thrive: pre-filling the sparse initial disparity map with interpolation. Interestingly, we find that pre-filling is also effective when injecting LiDAR depth into image features via early fusion, but for a fundamentally different reason, necessitating a distinct pre-filling approach. By combining both solutions, the proposed Guided RAFT-Stereo (GRAFT-Stereo) significantly outperforms existing LiDAR-guided methods under sparse LiDAR conditions across various datasets. We hope this study inspires more effective LiDAR-guided stereo methods.
format Preprint
id arxiv_https___arxiv_org_abs_2507_19738
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Leveraging Sparse LiDAR for RAFT-Stereo: A Depth Pre-Fill Perspective
Yoo, Jinsu
Jeon, Sooyoung
Huang, Zanming
Pan, Tai-Yu
Chao, Wei-Lun
Computer Vision and Pattern Recognition
We investigate LiDAR guidance within the RAFT-Stereo framework, aiming to improve stereo matching accuracy by injecting precise LiDAR depth into the initial disparity map. We find that the effectiveness of LiDAR guidance drastically degrades when the LiDAR points become sparse (e.g., a few hundred points per frame), and we offer a novel explanation from a signal processing perspective. This insight leads to a surprisingly simple solution that enables LiDAR-guided RAFT-Stereo to thrive: pre-filling the sparse initial disparity map with interpolation. Interestingly, we find that pre-filling is also effective when injecting LiDAR depth into image features via early fusion, but for a fundamentally different reason, necessitating a distinct pre-filling approach. By combining both solutions, the proposed Guided RAFT-Stereo (GRAFT-Stereo) significantly outperforms existing LiDAR-guided methods under sparse LiDAR conditions across various datasets. We hope this study inspires more effective LiDAR-guided stereo methods.
title Leveraging Sparse LiDAR for RAFT-Stereo: A Depth Pre-Fill Perspective
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2507.19738