METHOD AND APPARATUS FOR PROCESSING AN AUDIO SIGNAL

摘要

A method and an apparatus for processing an audio signal are provided to improve sound quality of the audio signal by reducing an amount of operations by decoding an expansion signal selectively. A downmixing unit(10) generates a downmix signal by downmixing a multi source audio signal. A downmix signal encoding unit(20) encodes the downmix signal. An ancillary signal encoding unit(30) encodes an ancillary signal. An expansion signal encoding unit(40) encodes an expansion signal. The encoded signals are transmitted to a multiplexer(50). The multiplexer generates a bit stream by multiplexing the downmix signal, the ancillary signal, and the expansion signal. The generated bit stream is transmitted to a decoding device. A demultiplexer(60) receives the bit stream and divides the downmix signal encoded from the bit stream, the encoded ancillary signal, and the encoded expansion signal. A downmix signal decoding unit(70) decodes the encoded downmix signal. An ancillary signal decoding unit(80) decodes the encoded ancillary signal. An expansion signal decoding unit(90) selectively decodes the encoded expansion signal. An upmixing unit(100) generates an audio signal by using the ancillary signal.