Digital broadcast transmitter, digital broadcast receiver, and audio description descriptor processing methods thereof

A digital broadcast transmitter comprising:

• a signal input unit which receives a main audio signal and an auxiliary audio signal;
• a descriptor generation unit which generates an audio description descriptor including auxiliary information;
• a signal merge unit which generates a digital broadcast signal by merging the generated audio description descriptor, the main audio signal, and the auxiliary audio signal;
• and
• a broadcast transmission unit which transmits the generated digital broadcast signal.

An audio description descriptor processing method of a digital broadcast receiver, the audio description descriptor processing method comprising:

• receiving a digital broadcast signal;
• separating a main audio signal, an auxiliary audio signal, and an audio description descriptor from the received digital broadcast signal;
• extracting auxiliary information from the audio description descriptor;
• mixing the main audio signal and the auxiliary audio signal based on the auxiliary information to generate an audio signal;
• and
• outputting the audio signal.

An audio description descriptor processing method of a digital broadcast transmitter, the audio description descriptor processing method comprising:

• receiving a main audio signal and an auxiliary audio signal;
• generating an audio description descriptor which includes auxiliary information;
• generating a digital broadcast signal by merging the generated audio description descriptor, the main audio signal, and the auxiliary audio signal;
• and
• transmitting the generated digital broadcast signal.