The following example from jsg/diffr/gom shows a seismic section before and after an application of sfpwd:
sfpwd takes two input files: a 2-D or 3-D seismic data, and the local slope estimated by sfdip and specified by dip= parameter. When applied to 3-D data, sfpwd can produce either one output (inline or crossline destruction) or two outputs (both inline and crossline desctructions). This is controlled by the which= parameter. Other parameters (nj1=, nj2=, order=) have the same meaning as the corresponding parameters in sfdip.