class_docstr: Compute mfcc features of every frame in speech, return a float tensor
  with size (num_channels, num_frames, num_frequencies).
docstr: Set params.
  :param config: contains fourteen optional parameters.
      --window_length                         : Window length in seconds. (float, default = 0.025)
      --frame_length                          : Hop length in seconds. (float, default = 0.010)
      --snip_edges                            : If True, the last frame (shorter than window_length) will
                            be cutoff. If False, 1 // 2 frame_length data will be padded
                            to data. (bool, default = True)
      ---raw_energy                           : If 1, compute frame energy before preemphasis and
                                    windowing. If 2, compute frame energy after
                                    preemphasis and windowing. (int, default = 1)
      --preEph_coeff                      : Coefficient for use in frame-signal preemphasis.
                                    (float, default = 0.97)
      --window_type                           : Type of window ("hamm"|"hann"|"povey"|"rect"|"blac"|"tria").
                                    (string, default = "povey")
      --remove_dc_offset                  : Subtract mean from waveform on each frame
                                    (bool, default = true)
      --is_fbank                                      : If true, compute power spetrum without frame energy. If
                                    false, using the frame energy instead of the square of the
                                    constant component of the signal. (bool, default = true)
      --output_type                           : If 1, return power spectrum. If 2, return log-power
                                    spectrum. (int, default = 1)
      --upper_frequency_limit         : High cutoff frequency for mel bins (if < 0, offset from
                                    Nyquist) (float, default = 0)
      --lower_frequency_limit         : Low cutoff frequency for mel bins (float, default = 20)
      --filterbank_channel_count      : Number of triangular mel-frequency bins.
                                   (float, default = 23)
      --coefficient_count         : Number of cepstra in MFCC computation.
                                   (int, default = 13)
      --cepstral_lifter           : Constant that controls scaling of MFCCs.
                                   (float, default = 22)
      --use_energy                :Use energy (not C0) in MFCC computation.
                                   (bool, default = True)
  :return: An object of class HParams, which is a set of hyperparameters as name-value pairs.
code: def params(cls, config=None):
      """
      Set params.
      :param config: contains fourteen optional parameters.
          --window_length				: Window length in seconds. (float, default = 0.025)
          --frame_length				: Hop length in seconds. (float, default = 0.010)
          --snip_edges				: If True, the last frame (shorter than window_length) will
                                be cutoff. If False, 1 // 2 frame_length data will be padded
                                to data. (bool, default = True)
          ---raw_energy				: If 1, compute frame energy before preemphasis and
                                        windowing. If 2, compute frame energy after
                                        preemphasis and windowing. (int, default = 1)
          --preEph_coeff			    : Coefficient for use in frame-signal preemphasis.
                                        (float, default = 0.97)
          --window_type				: Type of window ("hamm"|"hann"|"povey"|"rect"|"blac"|"tria").
                                        (string, default = "povey")
          --remove_dc_offset		    : Subtract mean from waveform on each frame
                                        (bool, default = true)
          --is_fbank					: If true, compute power spetrum without frame energy. If
                                        false, using the frame energy instead of the square of the
                                        constant component of the signal. (bool, default = true)
          --output_type				: If 1, return power spectrum. If 2, return log-power
                                        spectrum. (int, default = 1)
          --upper_frequency_limit		: High cutoff frequency for mel bins (if < 0, offset from
                                        Nyquist) (float, default = 0)
          --lower_frequency_limit		: Low cutoff frequency for mel bins (float, default = 20)
          --filterbank_channel_count	: Number of triangular mel-frequency bins.
                                       (float, default = 23)
          --coefficient_count         : Number of cepstra in MFCC computation.
                                       (int, default = 13)
          --cepstral_lifter           : Constant that controls scaling of MFCCs.
                                       (float, default = 22)
          --use_energy                :Use energy (not C0) in MFCC computation.
                                       (bool, default = True)
      :return: An object of class HParams, which is a set of hyperparameters as name-value pairs.
      """
  
      upper_frequency_limit = 0.0
      lower_frequency_limit = 20.0
      filterbank_channel_count = 23.0
      window_length = 0.025
      frame_length = 0.010
      output_type = 1
      sample_rate = 16000
      snip_edges = True
      raw_energy = 1
      preeph_coeff = 0.97
      window_type = "povey"
      remove_dc_offset = True
      is_fbank = True
      cepstral_lifter = 22.0
      coefficient_count = 13
      use_energy = True
      dither = 0.0
      is_log10 = False
  
      hparams = HParams(cls=cls)
      hparams.add_hparam("upper_frequency_limit", upper_frequency_limit)
      hparams.add_hparam("lower_frequency_limit", lower_frequency_limit)
      hparams.add_hparam(
          "filterbank_channel_count", filterbank_channel_count
      )
      hparams.add_hparam("window_length", window_length)
      hparams.add_hparam("frame_length", frame_length)
      hparams.add_hparam("output_type", output_type)
      hparams.add_hparam("sample_rate", sample_rate)
      hparams.add_hparam("snip_edges", snip_edges)
      hparams.add_hparam("raw_energy", raw_energy)
      hparams.add_hparam("preeph_coeff", preeph_coeff)
      hparams.add_hparam("window_type", window_type)
      hparams.add_hparam("remove_dc_offset", remove_dc_offset)
      hparams.add_hparam("is_fbank", is_fbank)
      hparams.add_hparam("cepstral_lifter", cepstral_lifter)
      hparams.add_hparam("coefficient_count", coefficient_count)
      hparams.add_hparam("use_energy", use_energy)
      hparams.add_hparam("dither", dither)
      hparams.add_hparam("is_log10", is_log10)
  
      if config is not None:
          hparams.override_from_dict(config)
  
      return hparams
  
file_path: delta/delta/data/frontend/mfcc.py
imports: import delta.compat
  from core.ops import py_x_ops
  from delta.utils.hparam import HParams
  from delta.data.frontend.base_frontend import BaseFrontend
  from delta.data.frontend.fbank import Fbank
  from delta.data.frontend.framepow import Framepow
  import copy
label_desc: Use image node_id 2 for calling the Mfcc obj's underlying member method code with example usage: obj.params(cls, config) and returns: hparams