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我想wav用巴特沃斯带通过滤一个文件。我尝试将wav文件转换为fftthen 以应用带通滤波器，然后再将ifft. 从图形上看，它似乎被过滤了一点，但是当我减少输入和输出wav时，音频没有区别，就像过滤器不起作用一样。有错误吗？

# FFT - Fast Fourier Transform
frequency,data = wavfile.read('Input_sound.wav')
signalFFT = fft(data)
def butter_bandpass_filter(data, lowcut, highcut, frequency, order):
    nyq = 0.5 * frequency
    low = lowcut / nyq
    high = highcut / nyq

    b, a = butter(order, [low, high], btype='bandpass')
    y = lfilter(b, a, data)
    return y 
funct=butter_bandpass_filter(signalFFT,2100,3400,44100,4)

filtered_sound=ifft(funct)
filtered_sound=sp.real(filtered_sound)
filtered_sound=sp.int16(filtered_sound/sp.absolute(filtered_sound).max()*32767)
wavfile.write('Filtered_ouput.wav',frequency,filtered_sound)
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1 回答 1

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查看lfilter 文档的示例，您似乎不需要执行 FFT，而是直接将 提供data给过滤器。然后就简单多了

frequency,data = wavfile.read('Input_sound.wav')

def butter_bandpass_filter(data, lowcut, highcut, frequency, order):
    nyq = 0.5 * frequency
    low = lowcut / nyq
    high = highcut / nyq

    b, a = butter(order, [low, high], btype='bandpass')
    y = lfilter(b, a, data)
    return y 

filtered_sound=butter_bandpass_filter(data,2100,3400,44100,4)
wavfile.write('Filtered_ouput.wav',frequency,filtered_sound)
于 2019-11-19T16:55:50.863 回答