Skip to main content
Article
100%
HD

Balinese palm‑leaf manuscripts, ancient witnesses of a rich culture, often suffer from mold, cracks and fading. To make them readable by computers, researchers compared ten classic binarization techniques—including Otsu, Niblack, Sauvola and ISODATA—with a deep‑learning model built on U‑Net and ResNet34. The model was trained on 256 × 256‑pixel blocks taken from two collections: 19 sheets of the Lontar Terumbalan series from Indonesia's National Library and 100 images of the AMADI Lontarset set. Results show the neural‑network approach far outperforms traditional methods. The highest Dice score reached 0.986, with accuracy 0.983, SSIM 0.938, RMSE 0.143 and PSNR 17.059. Among classic techniques, ISODATA performed best (Dice 0.957, accuracy 0.933) but still lagged behind deep learning. In practice, the network can separate text from degraded areas and background with near‑perfect precision, paving the way for more faithful digitisation and safer preservation of these priceless documents.

Bonus
100%
HD

The U‑Net ResNet34 model merges two key architectures: U‑Net, designed for semantic segmentation, and ResNet34, a 34‑layer residual network that eases deep representation learning without gradient degradation. Training on 256 × 256‑pixel patches captures fine details such as the delicate Balinese script strokes while preserving enough spatial context to separate text from degraded background. The loss function combines Dice loss and cross‑entropy, optimized with Adam at a 1e‑4 learning rate. To prevent overfitting, data augmentation (rotations, flips, brightness variations) and early stopping based on validation loss were employed. Evaluation metrics include Dice coefficient (overlap measure), SSIM (structural similarity) and PSNR (signal‑to‑noise ratio), offering a comprehensive view of binarization quality. Results show the network learns to recognize ink patterns even when partially corrupted, surpassing global or local threshold methods that struggle with non‑uniform contrast variations. This study highlights CNNs' potential for digital preservation of ancient texts, suggesting future extensions to other degraded media such as parchment or papyrus.

Ask AI

Explore key aspects of this story with 3 quick insights

Source

Authors:
Imam YuadiKhoirun Nisa'Nisak Ummi NazikhahYunus Abdul HalimA. Taufiq AsyhariChih-Chien Hu
Date Published:
Original Article www.mdpi.com
Fact-check verified on 15/06/2026
Read our Editorial Guidelines & AI Ethics Policy
Creative Commons License CC BY-NC-SA 4.0

Keep exploring

Discover the full archive of science bites or head back to home

Riconnessione al server... Aggiornamento della sessione in corso
Connessione interrotta Impossibile stabilire il collegamento
Sessione aggiornata Ricarica per visualizzare i contenuti