We're happy to announce our new paper (July, 2020), a joint work by Dr. Eyal Gofer and M.Sc. student Shachar Praisler under the supervision of Prof. Guy Gilboa.
Abstract
This work considers the problem of depth completion, with or without image data, where an algorithm may measure the depth of a prescribed limited number of pixels. The algorithmic challenge is to choose pixel positions strategically and dynamically to maximally reduce overall depth estimation error. This setting is realized in daytime or nighttime depth completion for autonomous vehicles with a programmable LiDAR.
Our method uses an ensemble of predictors to define a sampling probability over pixels. This probability is proportional to the variance of the predictions of ensemble members, thus highlighting pixels that are difficult to predict. By additionally proceeding in several prediction phases, we effectively reduce redundant sampling of similar pixels.
Our ensemble-based method may be implemented using any depth-completion learning algorithm, such as a state-of-the-art neural network, treated as a black box. In particular, we also present a simple and effective Random Forest-based algorithm, and similarly use its internal ensemble in our design.
We conduct experiments on the KITTI dataset, using the neural network algorithm of Ma et al. and our Random Forest based learner for implementing our method. The accuracy of both implementations exceeds the state of the art. Compared with a random or grid sampling pattern, our method allows a reduction by a factor of 4-10 in the number of measurements required to attain the same accuracy.
Paper - https://ieeexplore.ieee.org/abstract/document/9580693 (UPDATED! Accepted to TIP, 2021)
Github code - https://github.com/shacharp/Adaptive-LiDAR-Sampling
Algorithm flow (click for full-size)
Comparison videos (512 samples - top, depth prediction - bottom)
Var-based NN (ours):
Grid+NN:
RMSEs comparison:
Citation
@article{gofer2021adaptive, title={Adaptive LiDAR Sampling and Depth Completion using Ensemble Variance}, author={Gofer, Eyal and Praisler, Shachar and Gilboa, Guy}, journal={IEEE Transactions on Image Processing}, year={2021}, publisher={IEEE} }
Related works
Super-Pixel Sampler – a Data-driven Approach for Depth Sampling and Reconstruction (ICRA2020).
@inproceedings{wolff2020super,
title={Super-pixel sampler: a data-driven approach for depth sampling and reconstruction},
author={Wolff, Adam and Praisler, Shachar and Tcenov, Ilya and Gilboa, Guy},
booktitle={2020 IEEE International Conference on Robotics and Automation (ICRA)},
pages={2588--2594},
year={2020},
organization={IEEE}
}