“…Many low-cost image capture mechanisms have been proposed, mostly composed of off-the-shelf components (Li et al, 2006 ; Schumann et al, 2008 ; Lemahieu and Wyns, 2011 ; Huang et al, 2013 ). These methods either use new approaches (Mäenpää, 2005 ; Asadifard and Shanbezadeh, 2010 ; Lemahieu and Wyns, 2011 ) or use an open-source project such as Starburst and ITU Gaze Tracker (Ryan et al, 2008a ; Villanueva et al, 2009 ; Deng et al, 2010 ; Tafaj et al, 2011 ) (for Starburst and Gaze-Tracker methods refer to Li et al ( 2005 ) and San Agustin et al ( 2010 ), respectively).…”