[demo] support resampling audio

app.py

@@ -30,7 +30,9 @@ def recognition(audio):
     sr, y = audio
     # NOTE: model supports 16k sample_rate
     if sr != 16000:
-        y = librosa.resample(y, sr, 16000)
+        y = librosa.resample((y / max(np.max(y), 1)).astype(np.float),
+                             sr, 16000)
+        y = (y * (1 << 15)).astype("int16")
     ans = decoder_cn.decode(y.tobytes(), True)
     if ans is None:
         return "ERROR! No text output! Please try again!"