add some code

managed_components/78__esp-opus/dnn/training_tf2/ulaw.py

@@ -0,0 +1,19 @@
+
+import numpy as np
+import math
+
+scale = 255.0/32768.0
+scale_1 = 32768.0/255.0
+def ulaw2lin(u):
+    u = u - 128
+    s = np.sign(u)
+    u = np.abs(u)
+    return s*scale_1*(np.exp(u/128.*math.log(256))-1)
+
+
+def lin2ulaw(x):
+    s = np.sign(x)
+    x = np.abs(x)
+    u = (s*(128*np.log(1+scale*x)/math.log(256)))
+    u = np.clip(128 + np.round(u), 0, 255)
+    return u.astype('int16')