Papers › MegaSaM: Accurate, Fast, and Robust Structure and Motion from Casual Dynamic Videos

MegaSaM: Accurate, Fast, and Robust Structure and Motion from Casual Dynamic Videos

5 Dec 2024arXiv:2412.04463archive 2025-07-28

Zhengqi Li, Richard Tucker, Forrester Cole, Qianqian Wang, Linyi Jin, Vickie Ye, Angjoo Kanazawa, Aleksander Holynski, Noah Snavely

We present a system that allows for accurate, fast, and robust estimation of camera parameters and depth maps from casual monocular videos of dynamic scenes. Most conventional structure from motion and monocular SLAM techniques assume input videos that feature predominantly static scenes with large amounts of parallax. Such methods tend to produce erroneous estimates in the absence of these conditions. Recent neural network-based approaches attempt to overcome these challenges; however, such methods are either computationally expensive or brittle when run on dynamic videos with uncontrolled camera motion or unknown field of view. We demonstrate the surprising effectiveness of a deep visual SLAM framework: with careful modifications to its training and inference schemes, this system can scale to real-world videos of complex dynamic scenes with unconstrained camera paths, including videos with little camera parallax. Extensive experiments on both synthetic and real videos demonstrate that our system is significantly more accurate and robust at camera pose and depth estimation when compared with prior and concurrent work, with faster or comparable running times. See interactive results on our project page: https://mega-sam.github.io/

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get_camera_rays mega-sam/mega-sam/cvd_opt/geometry_utils.py community (archive-listed) unverified Apache-2.0 (permissive) · bda1ea37848c1a5f · report
gradient_loss mega-sam/mega-sam/cvd_opt/cvd_opt.py community (archive-listed) unverified Apache-2.0 (permissive) · de454ae3ade5d9ae · report
pose_distance mega-sam/mega-sam/cvd_opt/geometry_utils.py community (archive-listed) unverified Apache-2.0 (permissive) · 1e7d6a056f2488fa · report
read_cameras_binary mega-sam/mega-sam/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · 1f7b4cd3dea533ca · report
read_cameras_binary mega-sam/mega-sam/camera_tracking_scripts/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · c9dc32524dba1c3e · report
read_cameras_text mega-sam/mega-sam/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · b768293892633d35 · report
read_cameras_text mega-sam/mega-sam/camera_tracking_scripts/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · 35498794a9af2019 · report
read_next_bytes mega-sam/mega-sam/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · 735c9f07e56255b5 · report
read_next_bytes mega-sam/mega-sam/camera_tracking_scripts/colmap_read_model.py community (archive-listed) unverified Apache-2.0 (permissive) · f651b415cb3682d6 · report
resize_flow mega-sam/mega-sam/cvd_opt/preprocess_flow.py community (archive-listed) unverified Apache-2.0 (permissive) · 72464163e1ed4a8b · report
si_loss mega-sam/mega-sam/cvd_opt/cvd_opt.py community (archive-listed) unverified Apache-2.0 (permissive) · ac04d341cfd51f93 · report
sobel_fg_alpha mega-sam/mega-sam/cvd_opt/cvd_opt.py community (archive-listed) unverified Apache-2.0 (permissive) · 7e492e661d45f956 · report
to_homogeneous mega-sam/mega-sam/cvd_opt/geometry_utils.py community (archive-listed) unverified Apache-2.0 (permissive) · 71da5d76a02a0fe3 · report
warp_flow mega-sam/mega-sam/cvd_opt/preprocess_flow.py community (archive-listed) unverified Apache-2.0 (permissive) · b0ed5fdc9c9400a1 · report

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