Convert FITS data cube to JSON

fitstojson.py

# Requires astropy ("pip install astropy")
# Creates HUGE files 42MB > 430MB in my test

from astropy.io import fits
import json

# Change to your fits file
hdulist = fits.open("in.fits")

# My fits file only had one data cube in it
scidata = hdulist[0].data

z, x, y = scidata.shape

mn = scidata.min()
mx = scidata.max()
scidata -= mn
scidata /= (mx - mn)

datal = scidata.tolist()

exdata = {"x": x, "y":y, "z":z, "data": datal}

with open ('data.json', 'w') as fp:
    json.dump(exdata, fp, indent=4)