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+# MTIHighlightShadowFilter
+
+A experimental highlight and shadow adjust filter for MetalPetal.
+
+The implementation closely follows the highlight shadow operation in in GEGL/GIMP. 
+
+https://gitlab.gnome.org/GNOME/gegl/-/blob/42186a77b08431fb25851f88e03256bc347e9790/operations/common-gpl3+/shadows-highlights-correction.c
+
+The GIMP implementation closely follows its counterpart in the Darktable photography software.
+
+https://docs.gimp.org/2.10/en/gimp-filter-shadows-highlights.html