libmagick++-6-headers 8:6.9.10.23+dfsg-2.1ubuntu11.4 (amd64 binary) in ubuntu focal

 The Magick++ library is a set of C++ wrapper classes that provides access
 to the ImageMagick package functionality from within a C++ application.
 .
 This package includes header files needed to compile
 programs using Magick++.
 .
 This package is independent of channel depth.