Devanagari handwritten characters and digits recognition using ResNet197
Manoj Kumar Sharma1
Associate Professor, Manipal University Jaipur,Dehmi Kalan, Jaipur,Rajasthan,India1
Corresponding Author : Manoj Kumar Sharma
Recieved : 14-August-2024; Revised : 06-October-2025; Accepted : 08-October-2025
Abstract
Handwriting recognition is a challenging problem in image processing and machine learning, and research in this area has expanded significantly in recent years. The Devanagari script, with its rich linguistic and cultural heritage, forms the foundation of several major Indian languages. Digitizing handwritten Devanagari scripts enhances their visibility, accessibility, and global acceptance. Convolutional neural networks (CNNs) have played a crucial role in improving image processing, pattern recognition, and character recognition accuracy. In this study, a deep learning–based system using a residual neural network (ResNet197) was developed, trained, and evaluated for recognizing handwritten Devanagari characters and digits. The model was tested on three benchmark datasets and one combined dataset to ensure robustness and generalization. On the Devanagari handwritten character dataset (DHCD) consisting of 92,000 samples from the University of California, Irvine (UCI) machine learning repository, the model achieved 99.82% training accuracy, 98.47% validation accuracy, 0.18% training error, 1.53% validation loss, and 98.47% ± 0.2% test accuracy. On the Sampoorna Hindi Akshar Barakhadi Digital (SHABD) Devanagari dataset containing approximately 304,150 characters across 384 classes, it achieved 99.78% training accuracy, 98.27% validation accuracy, 0.22% training error, 1.73% validation loss, and 99.91% ± 0.5% test accuracy. On the handwritten Devanagari characters – Vowels and numerals dataset (~52,000 samples across 59 classes) from Mendeley Data, the model achieved 99.46% training accuracy, 98.27% validation accuracy, 0.54% training error, 1.73% validation loss, and 97.46% ± 0.4% test accuracy. Finally, when trained and evaluated on a combined dataset merging the DHCD and handwritten Devanagari characters – Vowels and numerals datasets (approximately 143,721 samples after merging overlapping classes), the ResNet197 model achieved 98.76% training accuracy, 97.53% validation accuracy, 1.24% training error, 2.47% validation loss, and 97.53% ± 0.3% test accuracy. These results demonstrate the strong generalization capability and robustness of the proposed ResNet197 model across diverse handwritten Devanagari datasets, confirming its potential for practical applications in multilingual handwritten text recognition.
Keywords
Handwriting recognition, Devanagari script, Deep learning, Convolutional neural network (CNN), Residual neural network (ResNet), Character recognition.
Cite this article
Sharma MK. Devanagari handwritten characters and digits recognition using ResNet197. International Journal of Advanced Technology and Engineering Exploration. 2025;12(131):1588-1609. DOI : 10.19101/IJATEE.2024.111101468
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