In this workshop we invite you to create Visual Cryptography with the help of a a detailed tutorial/zine available to download. You can upload your results in the folder Encrypted_Messages and/or email other participants your encrypted messages so they can print them and decrypt them. You can also upload the decrypted messages and photos of the printed versions in the folder Decrypted_Messages.
During our online meeting we will discuss how Virtual Cryptography works, troubleshoot any problems you encountered in your process, look into the participants uploads, and have a final reflection on the usability of visual encryption and other methods of concealing information in writing.
- steps to create Visual Cryptography (for the full tutorial download the zine)
- Select a message such as a text, numbers, barcode (photos are more difficult to encrypt/decrypt since the process of VC lessens the sharpness of the original image)
- Convert the selected message to a Black&White image.
- Feed the image to one of the python scripts included in the Software section below. It will generate the image shares.
- Upload the image shares to subfolders under the folder Encrypted_Messages, and /or send them by email to others.
- Print the shares on a transparency sheet and overlay them to decrypt the message. Or feed the shares to the relevant python script to generate the decrypted image. Upload results in the folder Decrypted_Messages.
- Online meeting to discuss how VC works (5 min), workshop outcome (10 min), troubleshoot problems you encountered (10 min), feedback on the workshop, usability of VC and other forms of secret writing (10 min).
- tools you need
For creating the images:
OR Gimp
OR Imagemagick
Blog post with a compilation of useful links to VC