This library is fork of (https://github.com/adamvr/arduino-base64).
All credits go to its author Adam Rudd.
I have only modified it a little, to be able to use it with stl strings.
But the algorithm remained untouched.
Library is header only, so you can just copy base64.h where you want it.
Or you can use CMake
cd base64; mkdir build; cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
Generates basic makefile
make check
Runs simple test that will generate random alphanum and binary strings, tries to encode/decode them and compares the input and decoded string
make install
Installs base64.h to /usr/include (depending on CMAKE_INSTALL_PREFIX)