This repository contains useful utilities for Gaussian gradient filtering of astronomical FITS images. The programs are described in A very deep Chandra view of metals, sloshing and feedback in the Centaurus cluster of galaxies, J.S. Sanders, A.C. Fabian, G.B. Taylor, H.R. Russell, K.M. Blundell, R.E.A. Canning, J. Hlavacek-Larrondo, S.A. Walker, C.K. Grimes, 2016, MNRAS, 457, 82 http://adsabs.harvard.edu/abs/2016MNRAS.457...82S and Detecting edges in the X-ray surface brightness of galaxy clusters, J.S. Sanders, A.C. Fabian, H.R. Russell, S.A. Walker, K.M. Blundell, 2016, MNRAS, accepted, http://arxiv.org/abs/1605.02911 All software is Copyright Jeremy Sanders and released under the GNU GPLv2+. gaussian_gradient_magnitude.py ------------------------------ The main program is gaussian_gradient_magnitude.py. This utility applies the gaussian gradient magnitude filter to an input fits image, using a particular scale, sigma, in pixels. Requirements: - Python 2.7, pyfits, numpy, scipy To run, type ./gaussian_gradient_magnitude.py in.fits out.fits sigma Where sigma is a floating point value >0 hideregions2 ------------ This is a tool to cosmetically hide point sources in fits images. It fills point sources with random values from the surrounding pixel region. See hideregions2/README for details. ggm_combine ----------- This is an interactive tool to combine fits images filtered on different scales. See ggm_combine/README for details.