class_docstr: speech feat entrypoint unittest
class_docstr_tok: ["speech","feat","entrypoint","unittest"]
docstr: test python feat interface 
docstr_tok: ["test","python","feat","interface"]
code: def test_py_feat_interface(self):
      """test python feat interface"""
      sr_out, samples = speech_feature.load_wav(
          self.wavfile, sr=self.sr
      )
      self.assertEqual(sr_out, self.sr)
  
      pspec = speech_feature.powspec_feat(
          samples,
          sr=self.sr,
          nfft=self.nfft,
          winlen=self.winlen,
          winstep=self.winstep,
      )
      self.assertEqual(pspec.shape, (426, 257))
  
      fbank = speech_feature.fbank_feat(
          pspec,
          feature_size=self.feature_size,
          sr=self.sr,
          nfft=self.nfft,
      )
      self.assertEqual(fbank.shape, (426, 40))
  
      fbank = speech_feature.delta_delta(fbank, sr=self.sr)
      self.assertEqual(fbank.shape, (426, 40, 3))
  
      feat_ = speech_feature.extract_fbank(
          samples,
          sr=self.sr,
          winlen=self.winlen,
          winstep=self.winstep,
          feature_size=self.feature_size,
      )
      self.assertEqual(feat_.shape, (426, 40, 3))
  
      samples = np.pad(samples, [0, 100], mode="constant")
      pspec = speech_feature.powspec_feat(
          samples,
          sr=self.sr,
          nfft=self.nfft,
          winlen=self.winlen,
          winstep=self.winstep,
      )
      self.assertEqual(pspec.shape, (427, 257))
      fbank = speech_feature.fbank_feat(
          pspec,
          feature_size=self.feature_size,
          sr=self.sr,
          nfft=self.nfft,
      )
      fbank = speech_feature.delta_delta(fbank, sr=self.sr)
      self.assertEqual(fbank.shape, (427, 40, 3))
  
file_path: delta/delta/data/feat/speech_feature_test.py
imports: import os
  from pathlib import Path
  import librosa
  import numpy
  import delta.compat
  from absl import logging
  from delta.data.feat import speech_ops
  from delta.data.feat import speech_feature
  from delta import PACKAGE_ROOT_DIR
label_desc: Use image node_id 8 for calling the SpeechFeatureTest obj's underlying member method code with example usage: obj.test_py_feat_interface() without return types