libb64 is a library of ANSI C routines for fast encoding/decoding data into and
from a base64-encoded format. C++ wrappers are included, as well as the source
code for standalone encoding and decoding executables.

Base64 uses a subset of displayable ASCII characters, and is therefore a useful
encoding for storing binary data in a text file, such as XML, or sending binary
data over text-only email.