1. Department of Informatics, Faculty of Science and Mathematics, Diponegoro University, Semarang 50275, Indonesia
2. Department of Computer Science and Electronics, Faculty of Mathematics and Natural Sciences, Gadjah Mada University, Yogyakarta 55281, Indonesia
3. Department of Ophthalmology, Faculty of Public Health Medicine and Nursing, Gadjah Mada University, Yogyakarta 55281, Indonesia