Abstract
Deep learning methods for optical flow estimation usually increase the receptive field of convolution through reducing image resolution, which results in loss of spatial detail information during feature extraction. In this paper, we introduce dilated convolution into feature pyramid network, which can extract multi-scale features containing more motion details and can further improve the accuracy of optical flow estimation. The unsupervised loss function is based on forward–backward consistency check and robust census transform that has a good constraint performance in the case of illumination changes, which can train an unsupervised learning optical flow model with higher accuracy. Our network is trained on FlyingChairs and KITTI raw datasets with an unsupervised manner and tested on MPI-Sintel, KITTI 2012 and KITTI 2015 benchmarks. The experimental results show the advantages of our method in unsupervised learning approaches.
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This work was supported in part by the State Grid Corporation Science and Technology Foundation under Grant 52022318001N, in part by the National Natural Science Foundation of China under Grant 61401113, and in part by the Natural Science Foundation of Heilongjiang Province of China under Grant LC201426.
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Yang, B., Xie, H., Li, H. et al. Unsupervised Optical Flow Estimation Based on Improved Feature Pyramid. Neural Process Lett 52, 1601–1612 (2020). https://doi.org/10.1007/s11063-020-10328-2
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DOI: https://doi.org/10.1007/s11063-020-10328-2