Patent ID: 7421304

Claim:
An audio signal processing device, comprising: a subband extracting means for generating a subband signal that expresses a fine-varying-strength of a basic frequency composition and a higher harmonic composition of an audio signal of a processing object that express a waveform of an audio sound, wherein the subband signal is not attached with an attaching signal; a data attaching means for generating an information-attached subband signal expressing a result of superimposing the attaching signal that expresses an attaching information of an attaching object to the subband signal that has been generated by the subband extracting means; and a pitch waveform signal generating means for obtaining the audio signal of the processing object and processing the audio signal into a pitch waveform signal by making a time interval of a region corresponding to a unit pitch of the audio signal substantially the same, wherein the subband extracting means generates the subband signal according to the pitch waveform signal, wherein the subband extracting means comprises: a variable filter for extracting the basic frequency composition of the audio sound of the processing object by making a frequency characteristic change according to a control and filtering the audio signal of the processing object; a filter characteristic determining means for specifying the basic frequency of the audio sound according to the basic frequency composition that has been extracted from the variable filter and controlling the variable filter with a frequency characteristic that masks a composition out of a portion nearby the specified basic frequency; a pitch extracting means for dividing the audio signal of the processing object into a region constructed by the audio signal in the unit pitch according to the basic frequency composition of the audio signal; and a pitch length fixing part for generating the pitch waveform signal with each time interval within the region being substantial the same by sampling each the region of the audio signal of the processing object with a substantially same number of samples.