“…Early real-time dense approaches (Stühmer et al, 2010;Newcombe et al, 2011) were able to estimate the image depth from monocular input, but their use of a dense voxel grid limited reconstruction to small volumes and to powerful GPU devices due to high memory and computation requirements. Also suffering from the scalability issue, KinectFusion (Izadi et al, 2011;Funk and Börner, 2016) directly sensed depth using active sensors and fused the high quality depth measurements over time to surfaces. The scalability issue has been resolved by voxel hierarchy approaches (Chen et al, 2013) or direct voxel block hashing (Kähler et al, 2015) to avoid storing unnecessary data for free space allowing scaling to unbounded scenes.…”