Patent ID: 8229738

Claim:
A method for differentiated digital processing of a sound signal, constituted in an interval of a frame by a sum of sines of fixed amplitude and of which a frequency is modulated linearly as a function of time, this sum being modulated temporally by an envelope, a noise of said sound signal being added to said signal, prior to said sum, comprising: a stage of analyzing making it possible to determine parameters representing said sound signal by calculating the envelope of the signal, calculating the sound signal of the pitch and its variation, applying to a temporal signal of an inverse variation of the pitch a temporal sampling of the sound signal with a variable sampling step, this step varying with an inverse value of the pitch variation, performing a Fast Fourier Transformation (FFT) of a pre-processed signal, extracting signal frequential components and their amplitudes from a result of the Fast Fourier Transformation, and calculating the pitch in a frequential domain and its variation with respect to the previously calculated pitch in order to improve a precision of the previously calculated pitch.