fix call

deepspeech/frontend/augmentor/impulse_response.py

@@ -34,6 +34,7 @@ class ImpulseResponseAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Add impulse response effect.

deepspeech/frontend/augmentor/noise_perturb.py

@@ -40,6 +40,7 @@ class NoisePerturbAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Add background noise audio.

deepspeech/frontend/augmentor/online_bayesian_normalization.py

@@ -48,6 +48,7 @@ class OnlineBayesianNormalizationAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Normalizes the input audio using the online Bayesian approach.

deepspeech/frontend/augmentor/resample.py

@@ -35,6 +35,7 @@ class ResampleAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Resamples the input audio to a target sample rate.

deepspeech/frontend/augmentor/shift_perturb.py

@@ -35,6 +35,7 @@ class ShiftPerturbAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Shift audio.

deepspeech/frontend/augmentor/spec_augment.py

@@ -163,7 +163,7 @@ class SpecAugmentor(AugmentorBase):
     def __call__(self, x, train=True):
         if not train:
             return
-        self.transform_feature(x)
+        return self.transform_feature(x)
 
     def transform_feature(self, xs: np.ndarray):
         """

deepspeech/frontend/augmentor/speed_perturb.py

@@ -83,6 +83,7 @@ class SpeedPerturbAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Sample a new speed rate from the given range and

deepspeech/frontend/augmentor/volume_perturb.py

@@ -41,6 +41,7 @@ class VolumePerturbAugmentor(AugmentorBase):
         if not train:
             return
         self.transform_audio(x)
+        return x
 
     def transform_audio(self, audio_segment):
         """Change audio loadness.