diff --git a/python/dsp.py b/python/dsp.py
index 85568b7..99e2018 100644
--- a/python/dsp.py
+++ b/python/dsp.py
@@ -176,9 +176,21 @@ def log_partition(xs, ys, subbands):
     return np.array(X), np.array(Y)
 
 
+
+
 samples = int(round(config.MIC_RATE * config.N_ROLLING_HISTORY / (2.0 * config.FPS)))
 mel_y, (_, mel_x) = melbank.compute_melmat(num_mel_bands=config.N_SUBBANDS,
                                            freq_min=config.MIN_FREQUENCY,
                                            freq_max=config.MAX_FREQUENCY,
                                            num_fft_bands=samples,
-                                           sample_rate=config.MIC_RATE)
\ No newline at end of file
+                                           sample_rate=config.MIC_RATE)
+
+def create_mel_bank(n_history):
+    global samples, mel_y, mel_x
+    config.N_ROLLING_HISTORY = n_history
+    samples = int(round(config.MIC_RATE * config.N_ROLLING_HISTORY / (2.0 * config.FPS)))
+    mel_y, (_, mel_x) = melbank.compute_melmat(num_mel_bands=config.N_SUBBANDS,
+                                               freq_min=config.MIN_FREQUENCY,
+                                               freq_max=config.MAX_FREQUENCY,
+                                               num_fft_bands=samples,
+                                               sample_rate=config.MIC_RATE)