Synopsis
		sfpgreywfl bg=None savefile= title= pclip=100 absclip=n scalebar=y barlabel= timetext=y bgcmap=viridis wflcmap=gray jsnap=1 aspect=1 tmin=None tmax=None figx=10 figy=8 xints=None yints=None fps=15 speedup=10 dpi=90 fontsize=16 verb=n

Common usage examples
* Plot to screen using default parameters
sfpgreywfl < wavefield.rsf bg=velocity.rsf
* Save to file using custom parameters
sfpgreywfl < wavefield.rsf bg=velocity.rsf jsnap=10 bgcmap=gray wflcmap=seismic fps=10 verb=y savefile=output.mp4

Parameters
		bool absclip=n [y/n] Clipping is done for all gathers rather than per frame (y/n)   int aspect=1 Aspect ratio   string barlabel= Colorbar label   string bg=None Background for animation. Zero if not supplied   string bgcmap=viridis Background colormap. See https://matplotlib.org/users/colormaps.html   float dpi=90 DPI   float figx=10 Figure x size in inches   float figy=8 Figure y size in inches   float fontsize=16 Font size   float fps=15 Frames per second (when saving file)   int jsnap=1 Number of timesteps at which to plot wavefield   float pclip=100 Clip amplitude percentage from (0-100)   string savefile= Save animation to file. If not present, display animation.   bool scalebar=y [y/n] Colorbar   float speedup=10 Delay between frames (in milliseconds) will be speedup*dt   bool timetext=y [y/n] Time text   string title= Plot title   float tmax=None Maximum time   float tmin=None Minimum time   bool verb=n [y/n] Verbosity flag   string wflcmap=gray Wavefield colormap (should be sequential)   int xints=None Max number of x intervals   int yints=None Max number of y intervals