Tool to decipher the windows cipher of Johann Balthasar Friderici, a technique presented as steganographic, using squares of 4 cells, painted black or white boxes, or filled with a point.
Friderici Cipher (Windows) - dCode
Tag(s) : Symbol Substitution, Steganography
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Friderici Cipher (Windows)
Friderici's Windows Decoder
Friderici's Windows Encoder
Answers to Questions (FAQ)
What are Friderici's windows? (Definition)
Friderici windows are the name given to a steganography technique used by Johann B. Friderici in his book Cryptographia. There he presents an illustration of a ruined building made up of 22 four-paned windows.
The windows are divided into squares of 4 squares, and each square represents a letter according to the configuration of the squares.
How to encrypt using Friderici's windows cipher?
The Friderici cipher is a substitution of the letters of the alphabet by a window according to the lookup table:
| A | .png) | B | .png) | C | .png) | D | .png) | E | .png) | F | .png) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| G | .png) | H | .png) | I | .png) | K | .png) | L | .png) | M | .png) |
| N | .png) | O | .png) | P | .png) | Q | .png) | R | .png) | S | .png) |
| T | .png) | U | .png) | W | .png) | X | .png) | Y | .png) | Z | .png) |
| dCode.fr | |||||||||||
Note the absence of the letters J and V which did not exist in the (german) alphabet at the time. The X is absent from the drawing but was proposed by Klaus Schmeh.
How to decrypt Friderici's windows cipher?
Friderici's decryption is a substitution of each window by a letter of the alphabet.
Example: The image of the building can be deciphered WIRHABENKEINPULVERMEHR (so wir haben kein pulver mehr that can be translated we have run out of powder)
How to recognize a Friderici's windows ciphertext? (Identification)
The message is a drawing or a series of square or rectangular symbols made up of 4 smaller squares filled or colored in 3 different ways. In the original version, the tiles are either white / blank, black / striped, or filled with a black dot in the center.
Friderici presents this coding as a steganographic technique, so expect to see it reproduced on the windows of a building or any type of design that can present these square / rectangular shapes.
When was Friderici's windows code invented?
Johann Balthasar Friderici published the book Cryptographia, oder geheime Schrifft mund und wurckliche Correspondenss in 1685.
Source code
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