utils.py 文件源码

def get_spectrograms(sound_file): 
    '''Extracts melspectrogram and log magnitude from given `sound_file`.
    Args:
      sound_file: A string. Full path of a sound file.

    Returns:
      Transposed S: A 2d array. A transposed melspectrogram with shape of (T, n_mels)
      Transposed magnitude: A 2d array.Has shape of (T, 1+hp.n_fft//2)
    '''
    # Loading sound file
    y, sr = librosa.load(sound_file, sr=hp.sr) # or set sr to hp.sr.

    # stft. D: (1+n_fft//2, T)
    D = librosa.stft(y=y,
                     n_fft=hp.n_fft, 
                     hop_length=hp.hop_length, 
                     win_length=hp.win_length) 

    # magnitude spectrogram
    magnitude = np.abs(D) #(1+n_fft/2, T)

    # power spectrogram
    power = magnitude**2 #(1+n_fft/2, T) 

    # mel spectrogram
    S = librosa.feature.melspectrogram(S=power, n_mels=hp.n_mels) #(n_mels, T)

    return np.transpose(S.astype(np.float32)), np.transpose(magnitude.astype(np.float32)) # (T, n_mels), (T, 1+n_fft/2)