The glamorous life of a jetsetting Hollywood superspy involves black-tie cocktail parties, amazing gadgets, and the ability to send and receive secret messages. You may not ever get to indulge in the first two, but you can send messages hidden in plain sight if you have the right tools.
Welcome to the world of steganography. It’s okay if you’ve never heard of it before. Steganography is a type of secretive communication that dates back hundreds of years. The modern digital version of it often involves hiding a message inside an image or sound file.
Steganography might not be for everyone, but it’s easy to try out thanks to software and apps that make it simple to get started. Plus, you’ll get to feel a little bit like you’re starring in your own Mission: Impossible movie.
Ready to play spy? While steganography sounds intriguing and even fun, it can have some very practical applications. You could use it to disguise private information on your computer in order to foil anybody who might be snooping. You could also use it as a way to send messages to friends or family as an alternative to popular secure messaging apps like WhatsApp, Threema, and Signal.
When you hide a file inside another file using this method, a casual viewer will just see what looks like a normal image or hear a normal audio file. Your recipient would have to know to decrypt the file in order to access the hidden message.
Get started with steganography
There are some ways to hide files inside others that require you to use the Windows Command Prompt or the Mac Terminal, but those methods are best left to people who are comfortable with a more technical approach to steganography. The rest of us can turn to handy software and apps to get the job done.
If you’re a Windows user, then check out QuickStego and DeepSound. QuickStego lets you hide text in a Bitmap image. You can send the image to someone or even upload it to the internet.
The recipient of the message can then load it into QuickStego to reveal what it says. The free software comes from the makers of QuickCrypto, a paid program that includes the steganography features of QuickStego, but can also encrypt messages for extra security.
Fans of hacker drama Mr. Robot might already be aware of DeepSound. The software appeared in the TV show, but it’s a real option you can use to hide data in audio files and also extract those files later.
The lead in Mr. Robot used DeepSound to hide data in music tracks, which he burned onto CDs that played just like normal albums. DeepSound has more of a learning curve than QuickStego, but also includes an encryption option that requires a password in order to access the hidden information.
Mobile steganography apps
Here’s one for Apple fans. Pictograph for iOS is a free, barebones steganography app that can hide a message and/or an image inside another image. It’s not super sophisticated, but it will give you a taste of how the process works. Saved images can be reopened in the app so the hidden messages can be read; there is also a password-protection option for an extra layer of security.
There are a host of steganography-related apps available for Android devices. One interesting option is Pixelknot from The Guardian Project, a global collective of software developers focused on open-source security software.
The Pixelknot app is free and lets you hide text inside images and then read the hidden messages. As with Pictograph, there is also a password option.
If you do decide to use a mobile app, remember that your message recipient will also need to have the app to read it on the other end. You can also use these for your own private projects, like storing secret messages that only you can access.
Steganography has endured as a way to communicate covertly because it’s clever and can be very effective when done right. Apps and software can get you started with it and people who are more technically inclined can choose to explore fancier types of steganography that let you hide larger and more complex files than just text or images.