DIGITAL SIGNAL TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To allow a receiver side to display characters such as emergency information together with a video image without the need for expanding/ decoding once a digital video signal to be sent to the receiver side that has already been high efficiency compression coded by a transmitter side. SOLUTION: A multiplexer 110 of a transmitter multiplexes a digital information signal expressing characters that are generated by an information stream generator 107 and to which N-stages of priority information is added onto a digital video signal and a digital audio signal and transmits the multiplexed signal to a receiver. Then the receiver discriminates whether or not a character denoted by the digital information signal is to be displayed on the basis of the priority information added to the digital information signal and displays the characters denoted by the digital information signal together with a video image expressed by the digital video signal when discriminating that the characters are to be displayed.