Abstract: A method for processing an audio signal is disclosed. The present invention includes obtaining a stereophonic audio signal including a speech component signal and other component signals, obtaining gain values for each channel of the audio signal, determining whether the audio signal is an inverse-phase mono signal including left and right channel whose phase is inverted, inverting a phase of the obtained gain value corresponding to the one channel of the audio signal when the audio signal is an inverse-phase mono signal, modifying the speech component signal based on the inverted phase of the gain value, and generating a modified audio signal including the modified speech component signal, wherein the modified audio signal is in-phase mono signal.

Abstract: An apparatus for controlling a volume of an audio signal and method thereof are disclosed, by which a volume of an input signal can be controlled by using a non-linear gain curve and a target volume of the input signal. The present invention includes receiving an input signal and reference information controlling a volume of the input signal; and adjusting a volume of the input signal with the reference information, wherein the reference information comprises at least one of metadata indicating characteristics of the input signal, output environment information indicating characteristics of an environment in proximity to the apparatus and stored reference information being transmitted from memory. Therefore, the present invention is able to control a volume of an input signal adaptively by using reference information, for example metadata, outside environment information and stored reference information.