Method and an apparatus for processing an audio signal

An audio decoder for processing an audio signal, the audio decoder comprising:

• a multiplexer configured to receive a downmix signal, a residual signal, and object information;
• an extracting unit configured to extract a background-object signal and a foreground-object signal from the downmix signal using the residual signal and object information, wherein the object information includes information for recreation of object signals from the downmix signal;
• an information generating unit configured to receive mix information including gain information for the background-object signal, and generate downmix processing information based on the object information and the mix information;
• and
• a rendering unit configured to generate an output signal including a modified background-object signal and a modified foreground-object signal,
• wherein the modified background object signal is obtained by modifying a gain of the background-object signal using the mix information, and
• wherein the modified foreground-object signal is obtained by modifying a gain of the foreground-object signal using the downmix processing information.

A non-transitory computer-readable medium having instructions stored thereon, which, when executed by a processor, causes the processor to perform operations, the computer-readable medium comprising:

• the processor configured to perform the operations including:
• receiving a downmix signal, a residual signal, and object information;
• extracting a background-object signal and a foreground-object signal from the downmix signal using the residual signal and object information;
• receiving mix information including gain information for the background-object signal;
• generating a downmix processing information based on the object information and the mix information;
• and
• generating an output signal including a modified background-object signal and a modified foreground-object signal,
• wherein the modified background-object signal is obtained by modifying a gain of the background-object signal using the mix information, and
• wherein the modified foreground-object signal is obtained by modifying a gain of the foreground-object signal using the downmix processing information.