libpng provides libraries to C and C++ to work with PNG files.
The below can be used to view all of the installations of libpng on a particular system, where this example uses Coeus.
$ module avail |& grep "libpng"
Utils/libpng/1.6.34/gcc-6.3.0
To best use libpng's libraries in a C or C++ program, refer to this libpng example usage.