Provided is a signal processing apparatus including: a transducer that performs scanning through the interior of an object and acquires received waveform data of a plurality of scanlines an intensity screening unit that outputs a high intensity position at which signal intensity calculated from the received waveform data is higher than a first predetermined value a correlation calculation unit that calculates a correlation value in a constant-width division for received waveform data of a first scanline and of a second scanline having a predetermined correlation with the first scanline a position extraction unit that extracts, as a candidate position of a singular region, a position which corresponds to a high intensity position and for which the correlation value is lower than a second predetermined value and an image processor that performs signal processing of generating image data of the object on the basis of the received waveform data.
