Computer Science & Technology

Light Field Depth Estimation with Information Entropy-Based Pre-Computed Occlusion Masks

  • CHEN Zhong ,
  • CHEN Changfeng ,
  • ZHANG Xianmin
Expand
  • School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China

Received date: 2025-03-19

  Online published: 2025-05-06

Supported by

the Joint Funds of the National Natural Science Foundation of China (Key Program)(U24A20108)

Abstract

Light field cameras capture synchronized spatial-angular information of lights, offering a new paradigm for 3D visual perception. Depth estimation, as a fundamental task in light field analysis, underpins the critical applications such as 3D reconstruction and visual odometry. However, occlusion-induced estimation errors remain a persistent challenge. This paper proposes an occlusion-aware depth estimation framework featuring two novel mo-dules: an entropy-based occlusion mask pre-computation method and a viewpoint screening-driven depth estimation algorithm. In the investigation, first, the light field occlusion in the polar plane diagram is modeled by analyzing the information entropy of micro-images array, and a local entropy extremum-based occlusion mask pre-computation approach is constructed, thus overcoming the limitations of conventional techniques in characterizing occluded regions. Subsequently, viewpoint screening is employed to eliminate the interference from occluded perspectives, thus effectively reducing estimation errors and decreasing the proportion of disparity outliers exceeding 0.03 pixels compared to other methods. The core contribution of this paper lies in establishing a theoretical connection between information entropy and light field occlusion, enabling a robust occlusion-aware depth estimation framework based on the information entropy of micro-images array. Experimental results on light field benchmark dataset demonstrate that the proposed method achieves superior performance in mean absolute error and 25th error percentile. Comparative ablation studies confirm the efficacy of the entropy-driven occlusion mask, thus highlighting the critical role of information entropy theory in the framework of light field depth estimation.

Cite this article

CHEN Zhong , CHEN Changfeng , ZHANG Xianmin . Light Field Depth Estimation with Information Entropy-Based Pre-Computed Occlusion Masks[J]. Journal of South China University of Technology(Natural Science), 2025 , 53(11) : 1 -8 . DOI: 10.12141/j.issn.1000-565X.250074

References

[1] 殷永凯,于锴,于春展,等 .几何光场三维成像综述[J].中国激光202148(12):293-312.
  YIN Yongkai, YU Kai, YU Chunzhan,et al .3D imaging using geometric light field: a review[J].China Laser202148(12):1209001/1-20.
[2] GERSHUN A .The light field[J].Journal of Mathe-matics and Physics193918(1/2/3/4):51-151.
[3] NG R .Digital light field photography[D].Palo Alto:Stanford University,2006
[4] TAO M W, HADAP S, MALIK J,et al .Depth from combining defocus and correspondence using light-field cameras[C]∥Proceedings of 2013 IEEE International Conference on Computer Vision.Sydney:IEEE,2013:673-680.
[5] WANG T C, EFROS A A, RAMAMOORTHI R .Occlusion-aware depth estimation using light-field ca-meras[C]∥Proceedings of 2015 IEEE International Conference on Computer Vision.Santiago:IEEE,2015:3487-3495.
[6] WANG T C, EFROS A A, RAMAMOORTHI R .Depth estimation with occlusion modeling using light-field cameras[J].IEEE Transactions on Pattern Analysis and Machine Intelligence201638(11):2170-2181.
[7] WILLIEM W, PARK I K, LEE K M .Robust light field depth estimation using occlusion-noise aware data costs[J].IEEE Transactions on Pattern Analysis and Machine Intelligence201840(10):2484-2497.
[8] WILLIEM W, PARK I K .Robust light field depth estimation for noisy scene with occlusion[C]∥Proceedings of 2016 IEEE Conference on Computer Vision and Pattern Recognition.Las Vegas:IEEE,2016:4396-4404.
[9] HAN K, XIANG W, WANG E,et al .A novel occlusion-aware vote cost for light field depth estimation[J].IEEE Transactions on Pattern Analysis and Machine Intelligence202244(11):8022-8035.
[10] BOLLES R C, BAKER H H, MARIMONT D H .Epipolar-plane image analysis:an approach to determining structure from motion[J].International Journal of Computer Vision19871(1):7-55.
[11] WANNER S, GOLDLUECKE B .Variational light field analysis for disparity estimation and super-resolution[J].IEEE Transactions on Pattern Analysis and Machine Intelligence201436(3):606-619.
[12] ZHANG S, SHENG H, LI C,et al .Robust depth estimation for light field via spinning parallelogram operator[J].Computer Vision and Image Understanding2016145:148-159.
[13] ZHOU P, SHI L, LIU X,et al .Light field depth estimation via stitched epipolar plane images[J].IEEE Transactions on Visualization and Computer Graphics202430(10):6866-6879.
[14] CHAO W, WANG X, WANG Y,et al .Learning sub-pixel disparity distribution for light field depth estimation[J].IEEE Transactions on Computational Imaging20239:1126-1138.
[15] WANG Y, WANG L, LIANG Z,et al .Occlusion-aware cost constructor for light field depth estimation[C]∥Proceedings of 2022 IEEE/CVF Conference on Computer Vision and Pattern Recognition.New Orleans:IEEE,2022:19777-19786.
[16] SHIN C, JEON H G, YOON Y,et al .EPINET:a fully-convolutional neural network using epipolar geome-try for depth from light field images[C]∥Proceedings of 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.Salt Lake:IEEE,2018:4748-4757.
[17] TSAI Y J, LIU Y L, OUHYOUNG M,et al .Attention-based view selection networks for light-field disparity estimation[C]∥Proceedings of the AAAI Conference on Artificial Intelligence.New York:AAAI,2020:12095-12103.
[18] HONAUER K, JOHANNSEN O, KONDERMANN D,et al .A dataset and evaluation methodology for depth estimation on 4D light fields[C]∥Proceedings of the 13th Asian Conference on Computer Vision.Taipei:Springer International Publishing,2017:19-34.
[19] BRADLEY D, ROTH G .Adaptive thresholding using the integral image[J].Journal of Graphics Tools200712(2):13-21.
[20] CHELLAPILLA K, PURI S, SIMARD P Y .High performance convolutional neural networks for document processing[C]∥Proceedings of the 10th International Workshop on Frontiers in Handwriting Recognition.La Baule:Suvisoft,2006:inria-00112631.
Outlines

/