Performance comparison of Convolutional Neural Networks for classifying Thai-Khmer characters in ancient Buddhist scriptures

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Sornchai Laksanapeeti
Sukumal Kitisin

Abstract

In Thailand, numerous significant Buddhist scriptures, like the Tripitaka, are preserved on paper or palm leaves inscribed with Khmer-Thai characters, posing a risk of future deterioration. Accurate transcriptions of these scriptures are crucial for delving into the historical evidence of Buddhism in Thailand. However, experts still face challenges in deciphering and transcribing Khmer-Thai characters into Thai script. This research endeavors to enhance this process by developing and comparing deep learning models employing Convolutional Neural Networks (CNNs) for Khmer-Thai character recognition. The study employs a learning framework comprising 10 distinct CNN models, including ResNet50 and ResNet50V2, utilizing datasets sourced from handwritten samples from the Dhammakayadi scriptures and Khmer-Thai alphabet textbooks. These datasets encompass 96 Khmer-Thai characters and are divided into training, validation, and test sets. Training is conducted over 10 epochs. Results indicate that among the 10 models developed, one exhibits the highest accuracy at 79.25%, with a training time of 250.72 seconds. In comparison, the model utilizing the ResNet50 architecture achieves an accuracy of 77.88%, requiring 1,514.13 seconds for training. These findings suggest that the CNN structure generated in this study holds promise for further refinement as a model for recognizing Thai-Khmer characters.

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