3D phenotypic measurement of bitter gourd seedlings based on monocular structured light

Authors

  • Bin Li Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China
  • Weiwei Duan Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China
  • Yanbin Li 1. Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China;2. School of New Energy Science and Engineering, Xinyu University, Xinyu 338004, Jiangxi, China
  • Yande Liu School of Mechanical and Automotive Engineering, Xiamen University of Technology, Xiamen 361024, Fujian, China
  • Ge Chen Chinese Academy of Agricultural Sciences Institute of Vegetables and Flowers, Beijing 100080, China
  • Shangtao Ouyang Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China
  • Youfei Hou Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China
  • Mingjun Zhang Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China
  • Nan Chen Institute of Intelligent Mechanical and Electrical Equipment Innovation, East China Jiaotong University, Nanchang 330013, China

Keywords:

fringe projection, phase unwrapping, 3D reconstruction, leaf phenotyping

Abstract

Accurate 3D morphological characterization is critical for precision breeding. However, traditional phenotypingmethods suffer from inherent limitations such as low efficiency and loss of dimensional information. To overcome theselimitations, this study proposes a robust three-dimensional phenotypic analysis framework based on the monocular FringeProjection Profilometry (FPP) method. This method is specifically optimized for the high-precision measurement of youngplant leaf features. The framework employs a hybrid decoding strategy combining 12-step phase shifting with complementarygray codes to resolve phase ambiguity and reconstruct dense point clouds at sub-millimeter resolution. It addresses theproblems of leaf occlusion and adhesion using the section segmentation method. Based on the Oriented Bounding Box (OBB)method of principal component analysis (PCA) and Delaunay triangulation technology, it achieves precise quantification of keyphenotypic parameters such as leaf length, width, inclination angle, and area. Systematic verification using 72 bitter gourdseedlings as samples indicates that this method has an extremely high consistency with manual measurement results: thedetermination coefficients (R2) for leaf length, leaf width, and leaf inclination angle reach 0.9992, 0.9991, and 0.9933respectively, with corresponding root mean square errors (RMSE) as low as 0.68 mm, 0.54 mm, and 0.92°, and the R2 for leafarea reaches 0.9996. This system achieves the complete process from raw scanning to parameter extraction in a low-cost, non-contact, and semi-automated manner, providing reliable data support for the digital perception and intelligent gradingstandardization of seedling growth dynamics in precision breeding.

Keywords: fringe projection, phase unwrapping, 3D reconstruction, leaf phenotyping

DOI: 10.25165/j.ijabe.20261904.10643

Citation: Li B, Duan W W, Li Y B, Liu Y D, Chen G, Ouyang S T, et al. 3D phenotypic measurement of bitter gourd seedlings based on monocular structured light. Int J Agric & Biol Eng, 2026; 19(4): 191–202.

References

[1] Li L, Zhang Q, Huang D F. A review of imaging techniques for plant phenotyping. Sensors, 2014; 14(11): 20078–20111.

[2] Jin X L, Zarco-Tejada P J, Schmidhalter U, Reynolds M P, Hawkesford M J, Varshney R K. High-throughput estimation of crop traits: a review of ground and aerial phenotyping platforms. IEEE Geosci. Remote Sens. Mag., 2021; 9(1): 200–231.

[3] Jeon Y J, Hong S, Lee T S, Park S H, Song G, Seo M G, et al. Volumetric deep learning-based precision phenotyping of gene-edited tomato for vertical farming. Plant Phenomics, 2025; 7(3): 100095.

[4] Miao Y L, Peng C, Wang L Y, Qiu R C, Li H, Zhang M. Measurement method of maize morphological parameters based on point cloud image conversion. Comput. Electron. Agric., 2022; 199: 107174.

[5] Akhtar M S, Zafar Z, Nawaz R, Fraz M M. Unlocking plant secrets: A systematic review of 3D imaging in plant phenotyping techniques. Comput. Electron. Agric., 2024; 222: 109033.

[6] Wu S, Wen W L, Wang Y J, Fan J C, Wang C Y, Gou W B, et al. MVS-Pheno: a portable and low-cost phenotyping platform for maize shoots using multiview stereo 3D reconstruction. Plant Phenom, 2020; 2020: 1848437.

[7] Wu S, Wen W L, Gou W B, Lu X J, Zhang W Q, Zheng C X, et al. A miniaturized phenotyping platform for individual plants using multi-view stereo 3D reconstruction. Front. Plant Sci., 2022; 13: 897746.

[8] Gao T, Zhu F, Paul P, Sandhu J, Doku H A, Sun J, et al. Novel 3D imaging systems for high-throughput phenotyping of plants. Remote Sens., 2021; 13(11): 2113.

[9] Yang T T, Ye J H, Zhou S Y, Xu A J, Yin J X. 3D reconstruction method for tree seedlings based on point cloud self-registration. Comput. Electron. Agric., 2022; 202: 107210.

[10] Hong S J, Kim J, Lee A. Real-time morphological measurement of oriental melon fruit through multi-depth camera three-dimensional reconstruction. Food Bioprocess Technol, 2024; 17: 5083–5052

[11] Paturkar A, Sen Gupta G, Bailey D. Plant trait measurement in 3D for growth monitoring. Plant Methods, 2022; 18: 59.

[12] Li Y C, Liu J Y, Zhang B, Wang Y G, Yao J F, Zhang X J, et al. Three-dimensional reconstruction and phenotype measurement of maize seedlings based on multi-view image sequences. Front. Plant Sci., 2022; 13: 974339.

[13] Hu C H, Li P P, Pan Z. Phenotyping of poplar seedling leaves based on a 3D visualization method. Int J Agric & Biol Eng, 2018; 11(6): 145–151.

[14] Zhu X H, Huang Z R, Li B. Three-dimensional phenotyping pipeline of potted plants based on neural radiation fields and path segmentation. Plants, 2024; 13(23): 3368.

[15] Jiang L Z, Sun J, Chee P W, Li C Y, Fu L S. Cotton3DGaussians: Multiview 3D Gaussian Splatting for boll mapping and plant architecture analysis. Comput Electron Agric., 2025; 234: 110293.

[16] Sato R, Bizen R, Dong S L, Hayashi S, Wang Z L, Lu J, et al. Vitality evaluation for Pacific oysters (Crassostrea gigas) through heartbeat visualization using image analysis technology. Food Qual. Saf., 2025; 9: fyaf020.

[17] Qin Z, Yu H, Wang C, Guo Y L, Peng Y X, Xu K. Geometric transformer for fast and robust point cloud registration. In: Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, New Orleans, LA, USA: IEEE. 2022; pp.11143–11152. doi: 10.1109/CVPR52688.2022.01086.

[18] Li Z P, Wang S S, Su Y P, Yu D Y. A method for measuring strawberry leaf area based on three-dimensional point cloud instance segmentation. IEEE Access, 2025; 13: 25339–25349.

[19] Zhu R S, Sun K, Yan Z Z, Yan X H, Yu J L, Shi J. Analysing the phenotype development of soybean plants using low-cost 3D reconstruction. Sci. Rep., 2020; 10: 7055.

[20] Atefi A, Ge Y, Pitla S, Schnable J. Robotic technologies for high-throughput plant phenotyping: contemporary reviews and future perspectives. Front. Plant Sci., 2021; 12: 611940.

[21] Xie X N, Zhang R R, Guo J, Lu L Y, Pan H Q, Luo X, et al. Strawberry disease detection algorithm based on YOLO11-strawberry. Food Qual. Saf., 2025; 9: fyaf027.

[22] Shen P, Jing X Y, Deng W Z, Jia H Y, Wu T T. PlantGaussian: Exploring 3D Gaussian splatting for cross-time, cross-scene, and realistic 3d plant visualization and beyond. Crop J., 2025; 13(2): 607–618.

[23] Li J, Qi X, Nabaei S H, Liu M, Chen D, Sun Q, Zhang X, et al. A survey on 3D reconstruction techniques in plant phenotyping: from classical methods to neural radiance fields (NeRF), 3D Gaussian splatting (3DGS), and beyond. Plant Phenomics, 2025; 100137. doi: 10.1016/j.plaphe.2025.100137

[24] Zhang C, Kong J J, Wang Z R, Tu C J, Li Y C, Wu D S, et al. Origami-inspired highly stretchable and breathable 3D wearable sensors for in-situ and online monitoring of plant growth and microclimate. Biosens. Bioelectron., 2024; 259: 116379.

[25] Gu J, Zhang Y W, Yin Y X, Wang R X, Deng J W, Zhang B. Surface defect detection of cabbage based on curvature features of 3D point cloud. Front. Plant Sci., 2022; 13: 942040.

[26] Arshad M A, Jubery T, Afful J, Jignasu A, Balu A, Ganapathysubramanian B, et al. Evaluating neural radiance fields for 3d plant geometry reconstruction in field conditions. Plant Phenomics, 2024; 6: 0235. doi: 10.34133/plantphenomics.0235.

[27] Maloof J N, Nozue K, Mumbach M R, Palmer C M. LeafJ: An ImageJ plugin for semi-automated leaf shape measurement. J. Vis. Exp., 2013(71): e50028.

[28] Getman-Pickering Z L, Campbell A, Aflitto N, Grele A, Davis J K, Ugine T A, et al. LeafByte: A mobile application that measures leaf area and herbivory quickly and accurately. Methods Ecol. Evol., 2019; 11(2): 215–221.

[29] Liu Z H, Hu X N, Lu S Y, Xu B, Bai C Y, Ma T, et al. Advances in plant-based raw materials for food 3D printing. Journal of Future Foods, 2025; 5(6): 529–541.

Downloads

Published

2026-09-03

How to Cite

(1)
Li, B.; Duan, W.; Li, Y.; Liu, Y.; Chen, G.; Ouyang, S.; Hou, Y.; Zhang, M.; Chen, N. 3D Phenotypic Measurement of Bitter Gourd Seedlings Based on Monocular Structured Light. Int J Agric & Biol Eng 2026, 19, 191-202.

Issue

Section

Information Technology, Sensors and Control Systems

Most read articles by the same author(s)

<< < 1 2