A method includes determining a connection line between two eyes in each piece of profile picture information by identifying profile picture information of each viewer of at least two viewers, and determining a positive direction of each connection line according to the connection line between the two eyes in each piece of profile picture information and a preset positive direction determining rule. When the positive directions of all the connection lines are the same, calculating an included angle between the positive direction of each connection line and a positive direction of a reference line, and performing averaging on all the included angles to obtain a first included angle; and determining a display mode of a screen according to the first included angle.