From: A one-dimensional slope detection approach
Edge
Min
Max
Mean
Std
Erf
0.6381
0.6891
0.6637
0.0149
tanh
0.6169
0.9932
0.6488
0.0503
sigmoid
0.4503
0.6705
0.6398
0.0193
ramp
0.7768
0.8565
0.8134
0.0221
step
0.6429
0
arctan
0.5531
0.9968
0.5798
0.0522