Patent ID: 8300834

Claim:
An audio signal processing device comprising: an audio signal obtaining unit which continuously obtains an audio signal; a storing unit which stores the audio signal obtained by the audio signal obtaining unit for a time period from a start point to an end point; a trigger signal obtaining unit which obtains a trigger signal at a trigger obtaining point after the start point; and a specifying unit which calculates an index value of a sound level by using the audio signal obtained by the audio signal obtaining unit for a time period from the trigger obtaining point to the end point, calculates an index value of a noise level by using the audio signal stored in the storing unit for a time period from a start point to the trigger obtaining point; divides the index value of the sound level by the index value of the noise level to calculate an S/N ratio and decides whether or not the S/N ratio satisfies a prescribed condition to specify a part showing a sound generating period in the audio signal obtained by the audio signal obtaining unit after the trigger signal is obtained.