Color Space Transformation to Identify the Disappearance of Syafaq as the Beginning of Isha Prayer

Rusli; Niswatul Kariimah; Utiyah Hikmah; Ibnor Azli Ibrahim

doi:10.15575/join.v11i2.1621

Authors

Rusli Physics Department, Science and Technology Faculty, UIN Maulana Malik Ibrahim Malang, Indonesia
Niswatul Kariimah Physics Education Department, Faculty of Teacher and Training Education, Universitas Jember, Indonesia
Utiyah Hikmah Physics Department, Science and Technology Faculty, UIN Maulana Malik Ibrahim Malang, Indonesia
Ibnor Azli Ibrahim Faculty of Sharia and Law, Universiti Islam Sultan Sharif Ali, Brunei Darussalam

DOI:

https://doi.org/10.15575/join.v11i2.1621

Keywords:

Color Transformation, L*a*b*, Syafaq , YCbCr, YUV

Abstract

Early prayer times began to be widely discussed in the past few years, since several opinions said that the beginning of prayer isha’ and shubuh need to be corrected. This study focused on image processing approach to analyze the disappearance of syafaq rays as an early sign of the start of the Isha’ prayer. The imagery data were taken in Lombok and Masalembu then transformed into different color spaces. RGB data transform to YUV, YCbCr, and L*a*b* spaces. The main contribution is evaluating these models to establish an objective, sensor-based baseline. Conceptually, L*a*b* is superior because it isolates chromaticity from luminance*, allowing the a∗ channel to track the vanishing reddish hue without being obscured by total light fluctuations. From L*a*b* color spaces have sensitively identified the disappearance of syafaq. A uniform typology of graphs was obtained in 4 color spaces as a sign that the initial physical analysis of beginning isha’ times. A uniform graphic typology was obtained, where the Isha' time is marked by a plateau (flattening curve), indicating the rays have completely vanished. Results of the start of prayer times with color space transformation to identify the start of isha times close to the agreement in Indonesia.

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