如果你正在寻找一个音符的音高，你会发现，沥青是由FFT产生的光谱频率峰值往往是不同的，尤其是对低注意事项。

If you are looking for the pitch of a musical note, you will find that pitch is often different from the spectral frequency peak produced by an FFT, especially for lower notes.

要找到从复杂的FFT频率峰值，你需要计算双方的实部和虚结果矢量幅度。

To find the frequency peak from a complex FFT, you need to calculate the vector magnitude of both the real and imaginary results.

mag(i) = sqrt(real[i]*real[i] + imag[i]*imag[i]);