1. A method of detecting a text associated with video, the method comprising: reading a t-th frame (where t is a positive integer) among frames forming the video as a current frame; determining whether there is a text area detected from a previous frame which is a (t−N)-th (where N is a positive integer) frame among the frames forming the video, in the current frame; upon determining that there is no text area detected from the previous frame in the current frame, detecting the text area in the entire current frame; and upon determining that there is the text area detected from the previous frame in the current frame, detecting the text area from a remaining area obtained by excluding from the current frame an area corresponding to the text area detected from the previous frame and verifying whether there is a text area in a next frame which is a (t+N)-th frame among the frames forming the video.