image,s,a,,,,image or image section to be plotted
floor,r,h,INDEF,,,minimum value to be contoured (INDEF for min)
ceiling,r,h,INDEF,,,maximum value to be contoured (INDEF for max)
zero,r,h,0,,,greyscale value of zero contour
ncontours,i,h,0,,,number of contours to be drawn (0 for default)
interval,r,h,0,,,contour interval (0 for default)
nhi,i,h,-1,,,"hi/low marking option: -1=omit, 0=mark h/l, 1=mark each pix"
dashpat,i,h,528,,,bit pattern for generating dashed lines
device,s,h,stdgraph,,,output device
title,s,h,"imtitle",,,optional title
preserve,b,h,yes,,,preserve aspect ratio of image?
label,b,h,yes,,,label major contours with their values?
fill,b,h,no,,,fill viewport regardless of device aspect ratio?
xres,i,h,64,,,resolution in x
yres,i,h,64,,,resolution in y
perimeter,b,h,yes,,,draw labelled perimeter around plot?
vx1,r,h,0.,,,NDC viewport x1
vx2,r,h,0.,,,NDC viewport x2
vy1,r,h,0.,,,NDC viewport y1
vy2,r,h,0.,,,NDC viewport y2
subsample,b,h,no,,,Subsample (vs blockaverage) to decrease resolution?
append,b,h,no,,,append to an old plot