Patent ID: 8743283

Claim:
A method of transmitting a digital broadcast signal, the method comprising: multiplexing video data, audio data, and supplementary data into MPEG2 transport stream, the supplementary data including an event information table (EIT) and a program map table (PMT), wherein the EIT or the PMT includes a caption service descriptor, wherein the caption service descriptor includes caption information indicating whether a digital television closed caption service is present in the video data or a line 21 closed caption service is present in the video data in accordance with electronic industry association (EIA) 708, wherein the caption service descriptor further includes language information defining a language associated with the closed caption service, and wherein the caption service descriptor further includes a caption service number that is defined only when the digital television closed caption service in accordance with electronic industry association (EIA) 708 is present; and transmitting the digital broadcast signal.