Patent ID: 8543231

Claim:
A method of processing an audio signal, comprising: receiving a downmix signal, object information and rendering information; obtaining downmix gain flag information indicating whether a downmix gain is included in the object information; generating downmix processing information using the object information and the rendering information based on the downmix gain flag information; generating multi-channel information using the object information and the rendering information; generating a processed downmix signal using the downmix processing information and the downmix signal; and decoding a multi-channel audio signal by applying the multi-channel information to the processed downmix signal, wherein the object information includes modified object level information or object level information, wherein the modified object level information is determined using a level of a modified object generated by applying the downmix gain to an object, wherein the object level information is determined using a level of the object, wherein the object information further includes object gain difference information indicating a ratio of contributing a left channel and a right channel of a stereo signal, if the downmix signal is a stereo signal, and wherein the object information includes the modified object level information, if the downmix gain flag information indicates that the downmix gain is not included in the object information.