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Old Chinese version

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Example 1: fftFormant01.m

% This example demos the effect of FFT for purely periodic signals au=myAudioRead('welcome.wav'); frame=au.signal(2047+15:2126+15); % A full fundamental period zeros=0*frame; frame=[frame; zeros; zeros; zeros; zeros; zeros]; %frame=au.signal(2047:2047+512-1); %frame=frame.*hamming(length(frame)); [mag, phase, freq, powerDb]=fftOneSide(frame, au.fs, 1); lMaxIndex=find(localMax(mag)); subplot(3,1,2); line(freq(lMaxIndex), powerDb(lMaxIndex), 'color', 'r', 'marker', 'o', 'linestyle', 'none'); fprintf('F1 = %f Hz\n', freq(lMaxIndex(1))); fprintf('F2 = %f Hz\n', freq(lMaxIndex(2))); fprintf('F3 = %f Hz\n', freq(lMaxIndex(3)));F1 = 114.843750 Hz F2 = 298.593750 Hz F3 = 505.312500 Hz

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Audio Signal Processing and Recognition (­µ°T³B²z»P¿ëÃÑ)