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Implementation of Convolutional Recurrent Neural Network for Vehicle Number Plate Identification in Raspberry Pi Based Parking System
Corresponding Author(s) : Rivaul Muzammil
Kinetik: Game Technology, Information System, Computer Network, Computing, Electronics, and Control,
Vol. 10, No. 4, November 2025
Abstract
The rapid growth of vehicles in Indonesia has created significant challenges in managing parking facilities. To address this issue, this study proposes an intelligent parking system based on automatic license plate character recognition. The system employs YOLOv8 (You Only Look Once) for license plate region detection and CRNN (Convolutional Recurrent Neural Network) for alphanumeric character recognition. Its architecture integrates a Raspberry Pi, camera module, and servo motor to enable automated license plate detection and recognition during vehicle entry and exit. YOLOv8 generates bounding boxes to isolate license plate regions, which are then processed as input for CRNN. The CRNN extracts visual features through convolutional layers and captures sequential relationships among characters using recurrent layers. The entire pipeline is deployed on Raspberry Pi with TensorFlow Lite to ensure efficient computation in resource-constrained environments. Experimental results demonstrate that YOLOv8 achieved a detection accuracy of 94.69%, with a precision of 98.32%, recall of 96.25%, and F1-score of 97.27%, while CRNN reached a character recognition accuracy of 93.8% across 30 license plates. Although some recognition errors occurred, such as misclassifying ‘G’ as ‘C’, 'W' as 'H', and 'Q' as 'O', the proposed system proved effective and feasible for embedded smart parking applications.
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- B. P. Statistik, “Perkembangan Jumlah Kendaraan Bermotor.”.
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References
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Y. Elhadi, O. Abdalshakour, and S. Babiker, “Arabic-numbers recognition system for car plates,” Proc. Int. Conf. Comput. Control. Electr. Electron. Eng. 2019, ICCCEEE 2019, no. September 2019, 2019. https://doi.org/10.1109/ICCCEEE46830.2019.9071288
P. Choorat, C. Sirikornkarn, and T. Pramoun, “License Plate Detection and Integral Intensity Projection for Automatic Finding the Vacant of Car Parking Space,” 34th Int. Tech. Conf. Circuits/Systems, Comput. Commun. ITC-CSCC 2019, pp. 4–7, 2019. https://doi.org/10.1109/ITC-CSCC.2019.8793297
W. Sugeng and R. Husaini, “Implementasi Convolutional Recurrent Neural Network untuk Identifikasi Plat Nomor Mobil pada Sistem Parkir Otomatis,” MIND (Multimedia Artif. Intell. Netw. Database) J., vol. 8, no. 2, pp. 142–157, 2023. https://doi.org/10.26760/mindjournal.v8i2.142-157
A. Menon and B. Omman, “Detection and Recognition of Multiple License Plate from Still Images,” 2018 Int. Conf. Circuits Syst. Digit. Enterp. Technol. ICCSDET 2018, pp. 1–5, 2018. https://doi.org/10.1109/ICCSDET.2018.8821138
Y. M. Alwaqfi and M. Mohamad, “A review of Arabic optical character recognition techniques & performance,” Int. J. Eng. Trends Technol., no. 1, pp. 44–51, 2020. https://doi.org/10.14445/22315381/CATI1P208
G. Sharma, “Performance Analysis of Vehicle Number Plate Recognition System Using Template Matching Techniques,” J. Inf. Technol. Softw. Eng., vol. 08, no. 02, 2018. https://doi.org/10.4172/2165-7866.1000232
G. Hajare, U. Kharche, P. Mahajan, and A. Shinde, “Automatic Number Plate Recognition System for Indian Number Plates using Machine Learning Techniques,” ITM Web Conf., vol. 44, p. 03044, 2022. https://doi.org/10.1051/itmconf/20224403044
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M. Talib, A. H. Y. Al-Noori, and J. Suad, “YOLOv8-CAB: Improved YOLOv8 for Real-time Object Detection,” Karbala Int. J. Mod. Sci., vol. 10, no. 1, pp. 56–68, 2024. https://doi.org/10.33640/2405-609X.3339
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X. Wang, W. Jiang, and Z. Luo, “Combination of convolutional and recurrent neural network for sentiment analysis of short texts,” COLING 2016 - 26th Int. Conf. Comput. Linguist. Proc. COLING 2016 Tech. Pap., pp. 2428–2437, 2016.
A. H. Wenhua Yu, Mayire Ibrayim, “Scene Text Recognition Based on Improved CRNN,” Information, no, pp. 1–14, 2023. https://doi.org/10.3390/info14070369
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S. Küçükdermenci, “Raspberry Pi-Based Real-time Parking Monitoring with Mobile App Integration,” 5th Int. Conf. Eng. Appl. Nat. Sci. August 25-26, 2024 Konya, Turkey, 2024.
P. Devi, T. Sharanmai, and T. Chandrika, “IoT Based Smart Vehicle Parking and Automatic Billing System Using RFID,” J. Eng. Sci., vol. 14, no. 04, pp. 922–934, 2023.
W. A. Jabbar, C. W. Wei, N. Atiqah, and A. M. Azmi, “Internet of Things An IoT Raspberry Pi-based parking management system for smart campus,” Fac. Electr. Electron. Eng. Technol. Univ. Malaysia Pahang, 26600 Pekan, Pahang, Malaysia, p. 100387, 2021. https://doi.org/10.1016/j.iot.2021.100387
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B. Shi, M. Yang, X. Wang, P. Lyu, C. Yao, and X. Bai, “ASTER: An Attentional Scene Text Recognizer with Flexible Rectification,” IEEE Trans. Pattern Anal. Mach. Intell., pp. 1–14, 2018. https://doi.org/10.1109/TPAMI.2018.2848939
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Kaggle, “Indonesian Plate Number,”.
Roboflow, “Plat Nomor Image Dataset,”.