base16384 - 2.3.1-1+b1 main

There are 16384 Chinese characters (from \u4E00 to \u8DFF)
as the "alphabet", just like what base64 did.
If the length of the data has a remainder after mod 7,
a unicode Chinese character \u3Dxx will be appended to present it
with xx ranging from 01 to 06.