Patent ID: 8638954
Filing Date: 2014-01-28
Classification: G10H,H04S

Abstract:
1. An audio signal processing apparatus comprising: an acquiring unit which acquires an input audio signal; a first filtering unit which outputs the audio signal acquired by the acquiring unit while attenuating frequency components of the audio signal except for frequency components of a first preset frequency band; a detecting unit which detects a sound volume level of the audio signal output from the first filtering unit; an amplitude limiting unit which calculates, as an amplitude limiting level, a constant ratio of the sound volume level detected by the detecting unit, and which limits an amplitude of a waveform of the audio signal output from the first filtering unit, wherein the amplitude to be limited is clipped at a level equal to or higher than the amplitude limiting level, thereby outputting an audio signal to which harmonics are added; a second filtering unit which outputs the audio signal output from the amplitude limiting unit while attenuating frequency components of the audio signal except for frequency components of a second preset frequency band including at least a part of the frequency band of the audio signal output from the first filtering unit, and a part of the frequency band of the harmonics; a compressing unit which outputs the audio signal output from the second filtering unit while compressing a dynamic range of the audio signal; and an adding unit which adds the audio signal output from the compressing unit to the input audio signal, and which outputs a result of the addition.