WCSLIB.jl

using WCSLIB

# create a wcsprm struct from scratch
w = wcsprm(2; # naxis
           cdelt = [-0.066667, 0.066667],
           ctype = ["RA---AIR", "DEC--AIR"],
           crpix = [-234.75, 8.3393],
           crval = [0., -90],
           pv    = [pvcard(2, 1, 45.0)])

# ... or from a FITS header
(ws,nrejected) = wcspih(header)
w = ws[1]  # ws is an array of wcsprm

# pixel coordinates -- note that, because julia's arrays are column-major,
# while wcs expects row-major, the x-values are in row 1 and the y-values in row 2
pixcrd = [0.0  24.0  45.0;
          0.0  38.0  98.0]

# convert pixel -> world coordinates
world = wcsp2s(w, pixcrd)

# convert world -> pixel coordinates
pixcrd = wcss2p(w, world)

# convert wcsprm to FITS header
header = wcshdo(w)