IRAF z-scale

[mileslucas]

Everyone's favorite DS9/IRAF feature!

This feature would allow some way of defining the image scale according to IRAF's z-scale. This method requires some simple statistics and fitting and should return a minimum and maximum color.

Example Usage

using AstroImages
img = load("image.fits")
cmin, cmax = zscale(img, args...)

plot(img, cmin=cmin, cmax=cmax)

References

• DS9 source code
• A hard to parse written description
• astropy

[mileslucas]

Hey, I realized I wrote this code a while back in the PlotUtils.jl repository, which allows using Plots.jl like

using Plots # Reexports PlotUtils
heatmap(transpose(img), clims=zscale)

I think we can copy a version of that here (although #2 would make this redundant), with improvements if any can be found.