F5 Steganography in Java

F5 is a steganography algo for hiding information in JPEG images. Unless other implementations it really hides it inside the image itself (not in metadata/comment fields or appended to the end of the file).

This project hosts the source code for a Java F5 steganography implementation as open source.

Credits for this go to Andreas Westfeld, it's base on his work.

Copy from original paper:

Abstract. Many steganographic systems are weak against visual and statistical attacks. Systems without these weaknesses offer only a relatively small capacity for steganographic messages. The newly developed algorithm F5 withstands visual and statistical attacks, yet it still offers a large steganographic capacity. F5 implements matrix encoding to improve the efficiency of embedding. Thus it reduces the number of nec- essary changes. F5 employs permutative straddling to uniformly spread out the changes over the whole steganogram.

Example Usage

Download the f5.jar, and start it via Java from the command line. To embed a file called msg.txt in a picture called pic.jpg run the following: java -jar f5.jar e -e msg.txt pic.jpg out.jpg

To extract a message from a picture call you call this: java -jar f5.jar x -e out.txt pic.jpg

You can also give a password to protect the data or specify the image quality for the JPEG, e.g.: java -jar f5.jar e -e msg.txt -p mypasswd -q 70 in.jpg out.jpg java -jar f5.jar x -p mypasswd -e out.txt in.jpg

Online Demos

currently there I only know of one webapp with an online demo running. If you find more, please let me know.