Dense switch statements containing only integer cases can be compiled into a JMP table
to gain performance. 

Depending on the density threshold the code size might be similar or even smaller.

Base64: the character set spreads from 43 to 122 (= 80) ==> density of 80 % (good)

hex: 0-9a-fA-F = 48..102 = 55 ==> 40 % (probably too low)