Large Scale Photometric Bundle Adjustment
Oliver J. Woodford, Edward Rosten
TL;DR
This work tackles large-scale photometric bundle adjustment by jointly refining dense scene geometry and camera parameters under a lighting-robust NCC cost. It introduces a memory-efficient VarPro-based optimization that operates on thousands of cameras and millions of landmarks using a ray-based, plane landmark parameterization, enabling accurate reconstruction on internet-scale image collections. Evaluations on Tanks & Temples show substantial gains in metric reconstruction accuracy over COLMAP, with ablations identifying the contributions of joint optimization, intrinsic refinement, and robust cost. The approach offers a complementary pathway to MVS, improving inputs for subsequent dense reconstruction and potentially enhancing online and offline large-scale 3D modeling tasks.
Abstract
Direct methods have shown promise on visual odometry and SLAM, leading to greater accuracy and robustness over feature-based methods. However, offline 3-d reconstruction from internet images has not yet benefited from a joint, photometric optimization over dense geometry and camera parameters. Issues such as the lack of brightness constancy, and the sheer volume of data, make this a more challenging task. This work presents a framework for jointly optimizing millions of scene points and hundreds of camera poses and intrinsics, using a photometric cost that is invariant to local lighting changes. The improvement in metric reconstruction accuracy that it confers over feature-based bundle adjustment is demonstrated on the large-scale Tanks & Temples benchmark. We further demonstrate qualitative reconstruction improvements on an internet photo collection, with challenging diversity in lighting and camera intrinsics.
