Positional Mimic Cipher (PM-Cipher)

[quimqu]

Moreover, in ciphers of the time it seems that it was common to encode digraphs like "ch" and doubled consonants like "ss" and "cc" as single letters, because otherwise they could be keys for cracking the encryption.

Well, working with digraphs is giving worse results in H2 and JSD. In fact, original double letters like "ss" will be hidden, as they should be ciphered with different EVA characters as they have different positions. I reached a JSD of 0,15 working with digraphs, but as there were repetitions digraph/simple chars, the deciphering became impossible. So I kept working with simple chars.

Optimising a bit my code, i still have the best results in English (Romeo and Juliet and Culpepper), with a JSD of 0,269, with a 28% of words generated contained in the Voynich EVA transliteration. You can see here the matrices Voynich / Ciphered Romeo and Juliet:




I would be happy to hear any comment and learn from you.