Estimation of fruit number in coffee trees by maturity level, based on color space weighting, using a new segmentation algorithm

Authors

Keywords:

Coffee fruit estimating, Computer Vision, Image Processing.

Abstract

Computer vision systems are essential for automating agricultural tasks such as disease detection and fruit defect identification. However, their application in coffee farming faces significant  challenges due to environmental variability and the complex structure of coffee trees, which complicate image acquisition. Thus, this study addresses two key questions: 1) Can low-cost, user-friendly  equipment adapt to crop conditions while ensuring image quality? 2) Can a computer vision algorithm accurately count and classify coffee beans with over 80% accuracy using data from low-cost cameras?  To answer these questions, an image acquisition system was developed based on the phenological characteristics of coffee plants, ensuring focused and consistent image capture. Additionally, a novel  algorithm was created, utilizing statistical analysis of color spaces to effectively separate fruits from the  background, segment images, and count fruits. The algorithm achieved accuracy rates, when  compared with a traditional approach, within the desired range for each coffee fruit class: green (83%),  green-olive (79%), cherry (86%), and raisin (80%). These results demonstrate the potential of this approach for accurate and efficient fruit processing in coffee farming, particularly when images are  captured directly from tree branches.

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Author Biographies

Mario, University of Sao Paulo

Mário Luiz Tronco holds a PhD in Mechanical Engineering from the University of Sao Paulo. He is
currently an Associate Professor with the Mechanical Engineering Department, Sao Carlos School of
Engineering - University of Sao Paulo. His areas of expertise include autonomous agricultural mobile
robots, artificial neural networks and computer vision applications.

Ingrid, Medellin Education Department, Medelin - Colombia

Ingrid Lorena Archote Pedrazza holds a Ph.D. in Mechanical Engineering from the University of Sao
Paulo. She has teaching experience in areas such as Artificial Intelligence, Expert Systems, Advanced
Topics in Machine Learning and Robotics. Currently, she is an official at the Ministry of Education of
Medellín, working as a teacher at I.E. San Antonio de Prado (Education institution).

Emerson, Federal University of São Carlos

Emerson Carlos Pedrino holds a Ph.D. in Electrical Engineering from University of Sao Paulo.
He is an Associate Professor with the Department of Computing, Federal University of Sao Carlos.
He completed his postdoctoral research with the University of York, U.K., from 2018 to 2019. He
specialized in real-time image and video processing using FPGAs, genetic programming, mathematical
morphology, remote sensing, robotic vision, machine learning, and manycore architectures.

Valencio, São Paulo State University - UNESP

Carlos Roberto Valêncio holds a Ph.D. in Computacional Physiscs from University of Sao Paulo.
Currently he is an Associate Professor with the Computer Science and Statistical Department, Sao
Paulo State University - UNESP. He works mainly with Big Data, Database, Knowledge Extraction
Process: Data Preparation and Attribute Selection, Data Clean, Data Mining, Spatial Data Mining,
Visual Data Mining; unconventional databases and georeferenced systems.

References

L. Kouadio, P. Tixier, V. Byrareddy, T. Marcussen, S. Mushtaq, B. Rapidel and R. Stone. "Performance of a process-based model for predicting robusta coffee yield at te regional scale in Vietnam". Ecological

Modelling, vol. 443, 2021. Available: 10.1016/j.ecolmodel.2021.109469

C. Brunn, P. Laderach, O. O. Rivera and D. Kirschke. "A bitter cup: climate change profile of global production of Arabica and Robusta coffee". Climatic Change, vol. 129, pp.89-101, 2015. Available: 10.1007/s10584-014-1306-x

V. Byrareddy, L. Kouadio, S. Mushtaq and R. Stone. "Sustainable Production of Robusta Coffee under a Change Climate: A 10-Year Monitoring of Fertilizer Management in Coffee Farms in Vietnam and Indonesia". Agronomy vol. 9, pp. 1-19, 2019. Available: 10.3390/agronomy9090499

M. K. V. Carr. "The water relations and irrigation requirements of coffee". Experimental Agriculture, vol. 37, pp. 1-36, 2001. Available: 10.1017/S0014479701001090

S. Castro-Tanzi, M. Flores, N. Wanner, T. V. Dietsch, J. Banks, N. Ureña-Retana and M. Chandler. "Evaluation of a non-destructive sampling method and a statistical model for predicting fruit load on individual coffee (coffea arabica) trees". Scientia Horticulturae, vol. 167, pp. 117-126, 2014. Available: 10.1016/j.scienta.2013.12.013.

H. M. R. Alves, M. M. L. Volpato, T. G. C. Vieira, D. A. Maciel, T. G. Gonçalves and M. F. Dantas. "Characterization and spectral monitoring of coffee lands in Brazil". International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives, vol.

, July, pp. 801-803, 2016. Available: 10.5194/isprsarchives-XLI-B8-801-2016

M. A. Zanella, R. N. Martins, F. M. Silva, L. C. C. Carvalho, M. C. Alves and J. T. F. Rosas. "Coffee yield prediction using high-resolution satellite imagery and crop nutritional status in Southeast Brazil". Remote Sensing Applications: Society and Environment, vol. 33, pp. 1-12, 2024. Available: 10.1016/j.rsase.2023.101092

D. M. Tsai and W. L. Chen. "Coffee plantation area recognition in satellite images using Fourier transform". Computers and Electronics in Agriculture, vol. 135, pp. 115-127, 2017. Available:

1016/j.compag.2016.12.020

Q. Zeng. "Algorithm based on marker-controlled watershed transform for overlapping plant fruit segmentation". Optical Engineering, vol. 48, no. 2, 2009. Available: 10.1117/1.3076212

R. Xiang, H. Jiang, Y. Peng, Y. Ying and J. Li. "Research on Recognition Method for Overlapping Tomatoes Based on Depth Map". Conference paper - American Society of Agricultural and Biological Engineers, no. 11, 2011. Available: 10.13031/2013.37754

J. C. Pastranaand T. Rath. "Novel image processing approach for solving the overlapping problem in agriculture". Biosystems Engineering, vol. 115, no. 1, pp. 106–115, 2013. Available:

1016/j.biosystemseng.2012.12.006

R. Xiang, H. Jiang and Y. Ying. "Recognition of clustered tomatoes based on binocular stereo vision". Computers and electronics in agriculture, vol. 106, pp. 75-90, 2014. Available: 10.1016/j.compag.2014.05.006

T. Pahikkala, K. Kari, H. Mattila, A. Lepisto, J. Teuhola, O. S. Nevalainen and E. Tyystjärvi. "Classification of plant species from images of overlapping leaves". Computers and Electronics in Agriculture, vol. 118, pp. 186–192, 2015. Available: 10.1016/j.compag.2015.09.003

M. Stein, S. Bargoti and J. Underwood. "Image Based Mango Fruit Detection, Localisation and Yield Estimation Using Multiple View Geometry". Sensors, vol. 16, no. 11, 2016. Available: 10.3390/s16111915

P. J. Ramos, F. A. Prieto, C. Montoya anbd C. E. Oliveros. "Automatic fruit count on coffee branches using computer vision". Computers and Electronics in Agriculture, vol. 137, pp. 9–22, 2017. Available:

1016/j.compag.2017.03.010

L. Yu, J. Xiong, X. Fang, Z. Yang, Y. Chen, X. Lin and S. Chen. "A litchi fruit recognition method in a natural environment using rgb-d images". Biosystems Engineering, vol. 204, pp. 50–63, 2021. Available:

1016/j.biosystemseng.2021.01.015

J. P. Rodriguez, D. C. Corrales, J. N. Aubertot and J. C. Corrales. "A computer vision system for automatic cherry beans detection on coffee trees". Pattern Recognition Letters, vol. 136, pp. 142–153, 2020. Available: 10.1016/j.patrec.2020.05.034

H. C. Bazame, J. P. Molin, D. Althoff and M. Martello, M. "Detection, classification, and mapping of coffee fruits during harvest with computer vision". Computers and Electronics in Agriculture, vol. 183, 2021. Available: 10.1016/j.compag.2021.106066

P. J. Ramos, J. Avendano and F. A. Prieto, F. A. "Measurement of the ripening rate on coffee branches by using 3d images in outdoor environments". Computers in Industry, vol. 99, pp. 83–95, 2018. Available: 10.1016/j.compind.2018.03.024

Published

2025-06-26

How to Cite

Tronco, M. L., Pedrazza, I. L. A. ., Pedrino, E. C., & Valencio, C. R. (2025). Estimation of fruit number in coffee trees by maturity level, based on color space weighting, using a new segmentation algorithm. IEEE Latin America Transactions, 23(8), 736–742. Retrieved from https://latamt.ieeer9.org/index.php/transactions/article/view/9330