Patent ID: 8359113

Claim:
A method of processing an audio signal, comprising: receiving downmix signal including object signals and preset information; transforming the downmix signal to frequency band downmix signal; estimating gain information from the transformed downmix signal; determining a direction of an object signal based on the gain information; determining blind information by estimating a level of the object signal corresponding to the direction; generating blind correlation information by using the gain information and the estimated level of the object signal; generating downmix processing information using the blind information, the blind correlation information, and the preset information; processing the downmix signal using the downmix processing information; generating multi-channel information using the blind information, the blind correlation information, and the preset information; and generating a multi-channel audio signal by applying the multi-channel information to the processed downmix signal, wherein the gain information indicates an extent that the object signal contained in the downmix signal contributes to a stereo channel of the downmix signal.