Patent ID: 7672744

Claim:
A method of decoding an audio signal performed by an audio coding system, comprising: receiving a downmix signal, object gain information and object level information, (a) the downmix signal generated by downmixing a multi-object audio signal including at least two object signals, wherein each object signal is capable of being located at a different virtual position, (b) the object gain information comprising an object gain value applied to one object signal for generating the downmix signal if the number of channels of the downmix signal is equal or greater than one and further including an object gain ratio indicating a gain difference between the at least two object signals contributing to the downmix signal if the number of channels of the downmix signal is equal or greater than two, and (c) the object level information being generated by dividing an object level with a normalization object level, the normalization object level being a maximum value among multiple object levels; calculating downmix processing information controlling the at least one object signal included in the downmix signal by using the object gain information and the object level information; calculating multi-channel information to upmix the downmix signal to a multi-channel audio signal by using the object gain information and the object level information; modifying the downmix signal by modifying at least one of gain and position of at least one object signal included in the downmix signal by applying the downmix processing information to the downmix signal; and generating the multi-channel audio signal by applying the multi-channel information to the modified downmix signal.