PAPERmaking! Vol11 Nr2 2025

T. Chirakitsakul et al.: Integration of Convolutional Neural Network and Image Processing

V. CONCLUSION AND FUTURE WORKS This study presented a novel methodology for fibril detection and fibrillation index computation by integrating adaptive image processing techniques with deep learning to address the inherent challenges in analyzing microscopic fibrils in pulp fibers. Leveraging convolutional neural networks (CNNs) and patch-based analysis, the method effectively mitigates issues such as low contrast, noise, and fibril morphology variability, enabling accurate detection even under challenging imaging conditions. Experimental results demonstrate significant advancements over traditional man- ual and semi-automated techniques, and achieve a reliable correlation between the computed fibrillation index and expert-labeled ground truth. The average absolute deviation of 0.449% underscores its reliability across diverse refining conditions and image qualities. While the proposed approach provides significant improvements in detection accuracy and efficiency, some limitations remain, particularly in handling low-contrast fibrils and artifacts resembling fibrils. These challenges present opportunities for future enhancements, including improved feature extraction techniques, the expansion of training datasets, and the integration of advanced noise- handling algorithms. In conclusion, this study represents a significant step forward in automating fibril detection, offering a scalable, reliable, and efficient solution for industrial applications in pulp and paper manufacturing. Beyond its immediate application, the proposed methodology holds potential for broader use in materials science, biomedical research, and other domains requiring precise analysis of small, intricate structures. We hope that this research will be one of AI-driven fibril analysis studies that will lead to future innovations that require the analysis of fibril-like microstructures, advancing both quality control and scientific discovery. REFERENCES [1] M. Kauppinen, F. M. A. Varkaus, and E. Tiikkaja, ‘‘Increasing needs for fiber quality measurements–results from tests for new solutions in quality control,’’ Metso Autom. Tech. Rep. , pp. 1–9, 2006. [Online]. Available: https://www.eucalyptus.com.br/artigos/2006_Need_Fiber+Measurements. pdf [2] P. Przybysz, M. Dubowik, E. Małachowska, M. Kucner, M. Gajadhur, and K. Przybysz, ‘‘The effect of the refining intensity on the progress of internal fibrillation and shortening of cellulose fibers,’’ BioResources , vol. 15, no. 1, pp. 1482–1499, Jan. 2020. [3] A. Ushakov, Y. Alashkevich, V. Kozhukhov, and R. Marchenko, ‘‘Role of external fibrillation in high-consistency pulp refining,’’ BioResources , vol. 18, no. 3, pp. 5494–5511, Jul. 2023. [4] J. Viguié, S. Kumar, and B. Carré, ‘‘A comparative study of the effects of pulp fractionation, refining, and microfibrillated cellulose addition on tissue paper properties,’’ BioResources , vol. 17, no. 1, pp. 1507–1517, Jan. 2022. [5] S. R. Österling, ‘‘Distributions of fiber characteristics as a tool to evaluate mechanical pulps,’’ Ph.D thesis, Dept. Chem. Eng., Fac. Sci., Mid Sweden University, Sundsvall, Sweden, 2015. [6] T. Kang and H. Paulapuro, ‘‘Effect of external fibrillation on paper strength,’’ in Proc. 91st PAPTAC Annu. Meeting , vol. 107, Montreal, QC, Canada, Jan. 2005, pp. 51–54. [7] R. J. Kerekes, D. Mcdonald, and F. P. Meltzer, ‘‘External fibrillation of wood pulp,’’ TAPPI J. , vol. 22, no. 6, pp. 363–371, Jul. 2023.

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