对原始语音进行上采样和下采样，分析对比他们的时域图和频谱图。最后对比原始语音、75HZ激励、150HZ激励以及噪声激励下的效果-SOME SIMPLE MANIPULATIONS OF SOUND USING DIGITAL SIGNAL PROCESSING The original sound and its spectrogram Downsampling the waveform downsampling Upsampling the waveform Li