Patent ID: 8548173

Claim:
A sound volume correcting device comprising: a variable gain device configured to control a gain of an input audio signal based at least in part on a gain control signal; a voice average level detecting device configured to detect an average level of a human voice signal in the input audio signal, wherein the voice average level detecting device includes: a voice interval detecting device configured to detect a voice interval which is a time interval including the human voice signal in the input audio signal, wherein the voice interval detecting device includes: a peak period detecting device configured to detect an inter-peak period of the input audio signal; a continuous identical period detecting device configured to detect a continuous identical period by detecting the identity of the adjacent inter-peak periods using the inter-peak period detected by the peak period detecting device; and a frequency detecting device configured to detect as the voice interval an interval including the continuous identical period detected by the continuous identical period detecting device or to detect as the voice interval a time interval in which the frequency of the continuous identical period is equal to or greater than a reference value; and a voice average level generating device configured to detect the average level of the input audio signal in the voice interval detected by the voice interval detecting device and to generate a continuous average level in which the detected average level of the voice interval is continuous; and a gain control signal generating device configured to generate the gain control signal for controlling the gain of the input audio signal using the average level of the human voice signal detected by the voice average level detecting device as a reference level and to supply the generated gain control signal to the variable gain device, wherein the gain control signal generating device generates the gain control signal for controlling the gain of the input audio signal using the continuous average level as the reference level.