Patent ID: 8078455

Claim:
An apparatus for distinguishing a vocal sound, the apparatus comprising: a framing unit to divide an input signal into frames, each frame having a predetermined length; a pitch extracting unit to determine whether each frame is a voiced frame or an unvoiced frame and extracting a pitch contour from the frame; a zero-cross rate calculator to respectively calculate a zero-cross rate for each frame using a computing device; a parameter calculator to calculate parameters including time length ratios with respect to the voiced frame and unvoiced frame determined by the pitch extracting unit, statistical information of the pitch contour, and spectral characteristics, wherein the time length ratios include a local voiced frame/unvoiced frame time length ratio, which is a time length ratio of a single voiced frame to a single unvoiced frame, and a total voiced frame/unvoiced frame time length ratio, which is a time length ratio of total voiced frames to total unvoiced frames; and a classifier to determine whether the input signal is a vocal sound using the calculated zero-cross rates and the calculated parameters output from the parameter calculator, wherein the calculated parameters output from the parameter calculator are the local voiced frame/unvoiced frame time length ratio, the total voiced frame/unvoiced frame time length ratio, the statistical information, and the spectral characteristics.