docstr: Regression of the mel-spectrogram for a voice signal
code: def testRegressionVoiceSignal(self):
      """Regression of the mel-spectrogram for a voice signal"""
  
      audio = MonoLoader(
          filename=join(testdata.audio_dir, "recorded/vignesh.wav"),
          sampleRate=self.sr,
      )()
  
      expected_file = join(
          filedir(),
          "tensorflowinputfsdsinet",
          "vignesh_melspectrogram_fsdsinet.npy",
      )
      expected = numpy.load(expected_file)
  
      found = self.melspectrogram(audio)
      found = found[: expected.shape[0], :]
  
      # Check comment on testRegressionDC.
      self.assertAlmostEqualMatrix(found, expected, 1e0)
  
file_path: essentia/test/src/unittests/spectral/test_tensorflowinputfsdsinet.py
imports: from essentia_test import *
label_desc: Use image node_id 4 for calling the TestTensorflowInputFSDSINet obj's underlying member method code with example usage: obj.testRegressionVoiceSignal() without return types