class_docstr: Convert STFT to fbank feats
  
  The arguments is same as librosa.filters.mel
  
  Args:
      fs: number > 0 [scalar] sampling rate of the incoming signal
      n_fft: int > 0 [scalar] number of FFT components
      n_mels: int > 0 [scalar] number of Mel bands to generate
      fmin: float >= 0 [scalar] lowest frequency (in Hz)
      fmax: float >= 0 [scalar] highest frequency (in Hz).
          If `None`, use `fmax = fs / 2.0`
      htk: use HTK formula instead of Slaney
code: def extra_repr(self):
      return ", ".join(f"{k}={v}" for k, v in self.mel_options.items())
  
file_path: espnet/espnet2/layers/log_mel.py
imports: from typing import Tuple
  import librosa
  import torch
  from espnet.nets.pytorch_backend.nets_utils import make_pad_mask
label_desc: Use image node_id 2 for calling the LogMel obj's underlying member method code with example usage: obj.extra_repr() and returns: str