  Learned local descriptors based on Convolutional Neural Networks (CNNs) have
achieved significant improvements on patch-based benchmarks, whereas not having
demonstrated strong generalization ability on recent benchmarks of image-based
3D reconstruction. In this paper, we mitigate this limitation by proposing a
novel local descriptor learning approach that integrates geometry constraints
from multi-view reconstructions, which benefits the learning process in terms
of data generation, data sampling and loss computation. We refer to the
proposed descriptor as GeoDesc, and demonstrate its superior performance on
various large-scale benchmarks, and in particular show its great success on
challenging reconstruction tasks. Moreover, we provide guidelines towards
practical integration of learned descriptors in Structure-from-Motion (SfM)
pipelines, showing the good trade-off that GeoDesc delivers to 3D
reconstruction tasks between accuracy and efficiency.
