# Geometric Loss Functions for Camera Pose Regression with Deep Learning

## TL;DR

This paper introduces geometry-based loss functions for deep learning camera pose regression, improving PoseNet's accuracy by leveraging scene geometry and automatic weighting of position and orientation.

## Contribution

It proposes novel geometric loss functions and an automatic weighting scheme for better camera pose regression in deep learning models.

## Key findings

- Significant performance improvements on indoor and city datasets.
- Enhanced robustness over naive loss functions.
- Effective joint regression of position and orientation.

## Abstract

Deep learning has shown to be effective for robust and real-time monocular image relocalisation. In particular, PoseNet is a deep convolutional neural network which learns to regress the 6-DOF camera pose from a single image. It learns to localize using high level features and is robust to difficult lighting, motion blur and unknown camera intrinsics, where point based SIFT registration fails. However, it was trained using a naive loss function, with hyper-parameters which require expensive tuning. In this paper, we give the problem a more fundamental theoretical treatment. We explore a number of novel loss functions for learning camera pose which are based on geometry and scene reprojection error. Additionally we show how to automatically learn an optimal weighting to simultaneously regress position and orientation. By leveraging geometry, we demonstrate that our technique significantly improves PoseNet's performance across datasets ranging from indoor rooms to a small city.

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Source: https://tomesphere.com/paper/1704.00390