12. A method of controlling a broadcasting receiver, the method comprising: receiving a broadcast signal of a currently tuned channel; determining whether caption data which comprises information on a caption window and caption text exists in the broadcast signal which is received; processing the caption data, determining an edge shape of a caption window corresponding to the information on the caption window, and generating the caption window and caption text according to the edge shape if it is determined that the caption data exists, wherein the caption data further comprises at least one of tail location information and tail direction information of a tail attached to an edge of the caption window, and wherein the generating the caption window and the caption text comprises generating the tail of the caption window according to the at least one of the tail location information and the tail direction information.
12. A method of controlling a broadcasting receiver, the method comprising: receiving a broadcast signal of a currently tuned channel; determining whether caption data which comprises information on a caption window and caption text exists in the broadcast signal which is received; processing the caption data, determining an edge shape of a caption window corresponding to the information on the caption window, and generating the caption window and caption text according to the edge shape if it is determined that the caption data exists, wherein the caption data further comprises at least one of tail location information and tail direction information of a tail attached to an edge of the caption window, and wherein the generating the caption window and the caption text comprises generating the tail of the caption window according to the at least one of the tail location information and the tail direction information. 14. The method of claim 12 , wherein the caption window is generated with the tail attached to the edge of the caption window based on the caption data such that the tail of the caption window identifies a speaker of the caption text.