preprocess.yaml

process:
  # extract kaldi fbank from PCM
  - type: fbank_kaldi
    fs: 16000
    n_mels: 80
    n_shift: 160
    win_length: 400
    dither: true
  - type: cmvn_json
    cmvn_path: data/mean_std.json
  # these three processes are a.k.a. SpecAugument
  - type: time_warp
    max_time_warp: 5
    inplace: true
    mode: PIL
  - type: freq_mask
    F: 30
    n_mask: 2
    inplace: true
    replace_with_zero: false
  - type: time_mask
    T: 40
    n_mask: 2
    inplace: true
    replace_with_zero: false