Weird noise introduced by `prepare_align.py`

[hellolzc]

After data preprocessing using prepare_align.py, strange noise appears in the audio file.
The following figure is the spectrum of the noise in the audio file in the demo directory.

[hellolzc]

The problem was solved by using soundfile to save audio

Modify the file preprocessor/ljspeech.py:

# from scipy.io import wavfile
import soundfile as sf

# ...

                wav = wav / max(abs(wav))
                sf.write(
                    os.path.join(out_dir, speaker, "{}.wav".format(base_name)),
                    wav,
                    sampling_rate,
                    subtype='PCM_16'
                )
                # wav = wav / max(abs(wav)) * max_wav_value
                # wavfile.write(
                #     os.path.join(out_dir, speaker, "{}.wav".format(base_name)),
                #     sampling_rate,
                #     wav.astype(np.int16),
                # )