I had ilmbase installed via brew, but no idea for what. Help appreciated!

[porg]

brew doctor on macOS 11.6.6 Big Sur shows me that ilmbase is deprecated. I have ilmbase installed and have no idea for what reason. I do not know whether it is safe for me to uninstall ilmbase.

brew deps --tree --installed ilmbase tells me it is not a dependency for another package. My diary shows that on the day on which I installed ilmbase I worked with both exiftool and imagemagick, in particular I found a solution How to batch convert PNGs to JPEGs and preserve timestamps in filesystem & EXIF header Can it be that one of the two has ilmbase as a "soft dependency", so it will start and work, but in order to use a particular function ilmbase is required? Help appreciated.

$  brew doctor

[…]
Warning: Some installed formulae are deprecated or disabled.
You should find replacements for the following formulae:
  ilmbase
[…]


$  brew deps --tree --installed ilmbase

ilmbase


$  brew info ilmbase
ilmbase: stable 2.5.7 (bottled) [keg-only]
OpenEXR ILM Base libraries (high dynamic-range image file format)
https://www.openexr.com/
Deprecated because it is not supported upstream!
/usr/local/Cellar/ilmbase/2.5.7 (87 files, 1.8MB) *
  Poured from bottle on 2021-08-xx at xx:xx
From: https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/ilmbase.rb
License: BSD-3-Clause
==> Dependencies
Build: cmake ✔
==> Caveats
ilmbase is keg-only, which means it was not symlinked into /usr/local,
because ilmbase conflicts with `openexr` and `imath`.

[waebbl]

ImageMagick has a (configurable) dependency on OpenEXR. New enough releases depend on OpenEXR-3, but older releases had dependencies on OpenEXR-2 / IlmBase. It might be, the version of ImageMagick, you once installed, had a dependecy on OpenEXR-2 and thus IlmBase. If you have recently updated this package, chances are high, that it already depends on OpenEXR-3 and Imath and doesn't need IlmBase anymore. You could try to re-install the package and verify it uses OpenEXR-3 and Imath. After this you should be able to safely remove IlmBase.

[porg]

^ Thanks for this detailed information. I will try and report back.