added missing function

electrical-network-frequency-analysis/notebooks/lib.py

@@ -0,0 +1,18 @@
+import sys
+from io import StringIO
+from pyenf_extraction.pyenf import pyENF
+
+def extract_enf_signal(wav_file_path):
+    mysignal = pyENF(filename=wav_file_path, nominal=50, harmonic_multiples=8, duration=0.1, strip_index=0)
+    x, fs = mysignal.read_initial_data()
+    spectro_strip, frequency_support = mysignal.compute_spectrogam_strips()
+    
+    sys.stdout = StringIO()
+    weights = mysignal.compute_combining_weights_from_harmonics()
+    sys.stdout = sys.__stdout__
+
+    OurStripCell, initial_frequency = mysignal.compute_combined_spectrum(
+        spectro_strip, weights, frequency_support
+    )
+
+    return mysignal.compute_ENF_from_combined_strip(OurStripCell,initial_frequency)