An encrypted journal entry - "The Prestige" Movie (2006)

I have written this small application originally to encrypt my journal entries without the need of a computer, the work evolved and I have added some functions to the algorithm, then I made it a public project.

The application supports some alphabets which you can choose among below, and it uses the One-Time Pad method. You’d need a key which is at least as long as the input text.

Encryption is given by the following formula:


While decryption is given by the following formula:



However, if the text were multilingual, then every encryptable character will be ciphered using a usable character of the key.

For example, if the input was:

dolor sit amet, consectetur

And the key was:

condimentum magna. Nullam in lectus

The characters “,” and “.” will be ignored during the procedure.

It will produce the output:

fcyrz emg tgqf, cuasrweptgz

If there were other characters like numbers or Arabic characters but these alphabets weren’t chosen from the input alphabets menu, they will be completely ignored.