Real-Time BISINDO Alphabet Recognition via Faster R-CNN Incorporating Skin Tone Diversity as a Classification Feature

Authors

  • Lilis Nur Hayati Universitas Muslim Indonesia
  • Anik Nur Handayani Universitas Negeri Malang
  • Wahyu Sakti Gunawan Irianto Universitas Negeri Malang
  • Rosa Andrie Asmara Politeknik Negeri Malang
  • Dolly Indra Universitas Muslim Indonesia
  • Nor Salwa Damanhuri Universiti Teknologi MARA (UiTM)

DOI:

https://doi.org/10.12928/biste.v8i3.15587

Keywords:

BISINDO, Faster R-CNN, Skin Color Features, Hand Gesture Recognition, Assistive Technology

Abstract

Indonesian Sign Language (Bahasa Isyarat Indonesia/BISINDO) enables communication for deaf individuals through hand gestures, yet limited public awareness creates significant barriers between deaf and hearing communities. Existing recognition systems often fail to generalize across diverse skin tones, reducing their effectiveness in inclusive real-world deployment. The contribution of this research is a BISINDO alphabet recognition system that integrates skin color features - extracted via HSV-based skin segmentation - as an additional preprocessing layer within the Faster R-CNN framework, explicitly improving detection robustness across varied skin tones. The dataset consists of 8,000 images from ten adult actors representing light, medium-brown, and dark skin tones, augmented through flipping and brightness variation, with a 90:10 training-to-testing ratio. The model was trained over 15,000 steps with a batch size of 24, selected through empirical validation to balance convergence stability and dataset size. Experimental results show that indoor conditions outperform outdoor settings due to controlled lighting. Light-skinned and dark-skinned participants achieved the highest accuracy of 87.5% and F1-score of 85.71%, while medium-brown-skinned participants showed slightly lower performance, likely attributed to greater variability in reflectance under mixed lighting. The system achieves 24 frames per second, demonstrating potential for real-time communication support. These findings confirm that Faster R-CNN with skin color feature integration is effective for BISINDO alphabet recognition, with skin tone diversity being a critical performance factor. Future work will explore larger participant pools and dynamic gesture recognition under varied real-world lighting scenarios.

Author Biographies

Anik Nur Handayani, Universitas Negeri Malang

Anik Nur Handayani received her Master’s degree in Electrical Engineering from Institut Teknologi Sepuluh Nopember (ITS), Surabaya, Indonesia, in 2008, and her Doctoral degree in Science and Advanced Engineering from Saga University, Japan. She is currently a lecturer at Universitas Negeri Malang, Indonesia. Her research interests include image processing, biomedical signal analysis, artificial intelligence, machine learning, deep learning, computer vision, and assistive technologies.

Wahyu Sakti Gunawan Irianto, Universitas Negeri Malang

received his Master’s degree in Computer Science from Universitas Indonesia, Jakarta, Indonesia, in 1997. He is currently a senior lecturer in the Department of Electrical Engineering at Universitas Negeri Malang, Indonesia. His research interests include computer science education, educational technology, intelligent systems, embedded and microcontroller applications, digital systems, and multimodal learning datasets.

Rosa Andrie Asmara, Politeknik Negeri Malang

He received his Bachelor’s degree in Electronics Engineering from Universitas Brawijaya, Indonesia, and his Master’s and Doctoral degrees in Computer Science from Institut Teknologi Sepuluh Nopember, Indonesia, and Saga University, Japan, respectively. He is currently a lecturer at Politeknik Negeri Malang, Indonesia, with research interests in machine learning, image understanding, and computer vision.

Dolly Indra, Universitas Muslim Indonesia

He earned his Doctoral degree in Information Technology from Universitas Gunadarma, Indonesia, in 2017. He is currently a lecturer at the Faculty of Computer Science, Universitas Muslim Indonesia, with research interests in image processing, computer vision, microcontroller systems, and information systems.

Nor Salwa Damanhuri , Universiti Teknologi MARA (UiTM)

She is an Associate Professor at the Centre for Electrical Engineering Studies, Universiti Teknologi MARA (UiTM), Penang Branch, Malaysia. Her research interests include biomedical engineering, digital signal processing, mathematical modeling, control systems, and solar photovoltaic systems.

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2026-06-15

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[1]
L. N. Hayati, A. N. Handayani, W. S. G. Irianto, R. A. Asmara, D. Indra, and N. S. Damanhuri, “Real-Time BISINDO Alphabet Recognition via Faster R-CNN Incorporating Skin Tone Diversity as a Classification Feature”, Buletin Ilmiah Sarjana Teknik Elektro, vol. 8, no. 3, pp. 811–823, Jun. 2026.

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