How to detect multibase of a CID

[SimonLab]

Given a CID the first step when decoding the CID is to determine which multibase is used
see https://github.com/multiformats/multibase

The CID(v1) encode this information on the first byte (ie the first 8 bits), see https://github.com/multiformats/cid#decoding-algorithm where:

• So the first step is to extract the first byte and to get a representation in hexadecimal. Then we can match with the multibase table to determine which encoding is used (the 0x is an indication to tell us that the text is in base16 which is hexadecimal)

• Check the implementations of multibase to know how the first byte is extracted
  see https://github.com/multiformats/js-multibase

[SimonLab]

Knowing the encoding is in fact simple.

• Get the first byte/letter
• match this first letter with the multibase table with the code column
• check the encoding column

see