This New App Lets You Hide Secret Messages in Your Facebook Photos

Tweet-length password-protected messages, hidden within seemingly innocuous Facebook photos

This photograph has a secret, but without the right password you’ll never learn it. Photo: Colin Schultz

Open your Facebook page. Go ahead. Chances are, your timeline is flooded with photos: photos of food, photos of your friend’s kids, silly little images captioned with bold text and gorgeous images someone lifted from around the net. What if, veiled within those ever-pervasive images, was something more—a clue, a secret, a hidden message masked from prying eyes?

A new web app, Secretbook, says Wired, enables you to do just that. An add-on for Google’s Chrome browser, Secretbook lets you process a photo, embedding it with a tweet-length, password-protected message (140 characters or less) that you can then share widely to Facebook. No one will be able to parse your message unless they a) know to look for one in the first place and b) know the secret code.

Secretbook, says Wired, is “the first time anyone’s managed to figure out how to automate digital steganography — the practice of concealing messages inside computer files — through Facebook, the world’s biggest social media platform. Unlike cryptography, which uses ciphertext to encrypt messages, steganographic messages are simply hidden where no one would think to look.”

Messages hidden in photos is not new, but because Facebook crushes and compresses your photos when you upload them, finding a way to preserve the message without it getting garbled was the key. But the makers of Secretbook do have a warning for you:

This app is a toy and does NOT provide military grade security. Please do not use it for terrorism or other bad things (you will get caught).

Okay fine here you go:

The code translation isn’t perfect, but it’s a fun way to pass secret notes in public. Click to legibilize.

More from Smithsonian.com:

World War II Code Writers Were So Good We Still Don’t Know What They Were Saying
Cracking a German Secret Society’s Centuries-Old Encrypted Code
Can Computers Decipher a 5,000-Year-Old Language?

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