http://bkg5ofjslnbyqvu55sjonpdyp3wmfsgq23u7vpk3wxn7ewgdeocpgwid.onion?page=article&article=Steghide%3A+A+Beginner%E2%80%99s+Guide+to+Secure+Data+Hiding+in+Plain+Sight.html
Steghide is an open-source steganography tool that allows users to hide data within different types of files, such as JPEG, BMP, WAV, and AU. Developed with ease of use and strong encryption in mind, it can conceal any type of file (e.g., text, image, or executable) inside another file, referred to as the "cover file."