Agc - Automatic gain control
Agc window=200 detect=0 dwind=10 thresh=25. < in.H > out.H
 length of the window in number of samples
 length od the detection window in number of samples
 detection off ( Default value ) 1 detection on
standard seplib parameters
Gain program with first arrival detection
Agc gains seismic traces by normalizing each sample by the power of a window of samples surrounding that point.
When the detect= is set to 1, agc is not applied on a trace until a first arrival is detected. The first arrival is detected when a moving dwind exceeds an initial dwind by a threshhold factor.