Update smart_pad.py

tools/smart_pad.py

@@ -12,24 +12,36 @@ from tools.file import AUDIO_EXTENSIONS, list_files
 
 threshold = 10 ** (-50 / 20.0)
 
-
 def process(file):
     waveform, sample_rate = torchaudio.load(str(file), backend="sox")
+    if waveform.size(0) > 1:
+        waveform = waveform.mean(dim=0, keepdim=True)
+
     loudness = librosa.feature.rms(
         y=waveform.numpy().squeeze(), frame_length=2048, hop_length=512, center=True
     )[0]
+
     for i in range(len(loudness) - 1, 0, -1):
         if loudness[i] > threshold:
             break
 
-    silent_time = (len(loudness) - i) * 512 / sample_rate
+    end_silent_time = (len(loudness) - i) * 512 / sample_rate
 
-    if silent_time <= 0.3:
-        random_time = random.uniform(0.3, 0.7)
+    if end_silent_time <= 0.3:
+        random_time = random.uniform(0.3, 0.7) - end_silent_time
         waveform = F.pad(
             waveform, (0, int(random_time * sample_rate)), mode="constant", value=0
         )
 
+    for i in range(len(loudness)):
+        if loudness[i] > threshold:
+            break
+
+    start_silent_time = i * 512 / sample_rate
+
+    if start_silent_time > 0.02:
+        waveform = waveform[:, int((start_silent_time - 0.02) * sample_rate) :]
+
     torchaudio.save(uri=str(file), src=waveform, sample_rate=sample_rate)