Bilkent University
Department of Computer Engineering


Sun Position Estimation on Time-Lapse Videos for Augmented Reality Applications


Hasan Balcı
MSc Student
(Supervisors: Prof. Dr. Ugur Güdükbay)
Computer Engineering Department
Bilkent University

Realistic illumination of virtual objects on Augmented Reality (AR) environments is important in terms of achieving visual coherence. This thesis proposes a novel approach that facilitates the illumination estimation on time-lapse videos and gives the opportunity to combine AR technology with time-lapse videos in a visually consistent way. The proposed approach works for both outdoor and indoor environments where the main light source is the Sun. We first modify an existing illumination estimation method that aims to obtain sparse radiance map of the environment in order to estimate the initial Sun position. We then track the hard ground shadows on the time-lapse video by using an energy-based pixel-wise method. The proposed method aims to track the shadows by utilizing the energy values of the pixels that forms them. The method is tested on various time-lapse videos recorded on outdoor and indoor environments and the tests show that the results are successful in terms of accuracy and the method works in real time.


DATE: 31 July, 2015, Friday @ 10:00