png2c_ucg is a non-AVR program that converts a png image to h-file
with an array or if necessary to multiple arrays of pixels.
It also creates an inline static function which calls the array(s) that
can be called in your AVR project.

To build the program:
  gcc -Wall -o png2c_ucg png2c_ucg.c -lpng

If library libpng is not available with MinGW/Msys2 use:
  pacman -S mingw64/mingw-w64-x86_64-libpng