libpng++-dev 0.2.10-1 (s390x binary) in ubuntu focal

 PNG++ aims to provide simple yet powerful C++ interface to libpng, the
 Portable Network Graphics (PNG) reference implementation library.
 .
 Using raw libpng in C++ may impose serious challenge since lots of
 precautions must be taken to handle initialization/deinitialization of
 control structures as well as handling errors correctly. With png++
 you can read or write PNG images just in a single line of C++ code.