How to Hide Data in Image, Audio & Video Files: Steganography

Ever wondered to know how to hide secret messages in images, audio and video files? Well, in this post I will take you through a concept called steganography using which,it is possible to hide your secret information in image files, songs or any other file of your choice. At the end of this post, you can also download free stegnographic tools and start hiding your data.
What is Steganography?
Steganography is a means of obscuring data where secret messages are hidden inside computer filessuch as images, sound files, videos and even executable files so that, no one except the sender and the receiver will suspect the existence of stealth information in it. Steganography may also involve the usage of cryptography where the message is first encrypted before it is concealed in another file. Generally, the messages appear to be something else such as an image, sound or video so that the transfer of secret data remains unsuspected.
The main advantage of steganography over other methods such as cryptography is that, it will not arose suspicion even if the files fall in the hands of a third party. Unlike cryptographic messages, stegnographic messages will no way attract the attention of a third party bythemselves. Thus stegnanography has an upper hand over cryptography as it involvesboth encryption and obscurity.
What are the Applications of Steganography?
Steganography is mainly used to obscure confidentialinformation/data during storage or transmission. For example, one can hide a secret message in an audio file and send this to another party via email instead of sending the message in the textual format. The receiver on theother end will decrypt the hidden message using the private decryption key. In aworst case scenario, even if a third party does manage to gain access to the email, all he can find is the audio file and not the hidden data inside it. Other usage of steganography include digital watermarking of images for reasons such as copyright protection. Eventhough steganographyhas many useful applications, some may use this technique for illegitimate purposes such as hiding a pornographic content in other large files. Roumors about terrorists using steganography for hiding and communicating their secret information andinstructions are also reported. An article claiming that, al-Queda had used steganography to encode messages in images and transported